What is the difference between "synergistic" and "synergetic"?

Question: What is the difference between "synergistic" and "synergetic"? I believe they both speak of the cooperation of multiple things to produce an output, but how do they differ?
Comment: It would be tempting to say that any difference relates to the difference between synergy and synergism, but a quick search suggests that there is no consistent correlation between noun and adjectival forms across several fields of use.
Comment: A slight distinction exists between ***synergetic*** & ***synergistic***, a term also used scientifically in med., anat., phys. & pharmacology. The latter use implies a net gain through the combined action of two muscles, hormones, chemical agents, etc; that is greater than the sum of the constituent elements acting independently. *Synergetic*, while connoting the simultaneous, motion-impelling action of multiple forces, makes allowance for the vector nature of forces in the physical sciences. [based on Fergus J. Wood,   http://www.springerreference.com/docs/html/chapterdbid/30915.html]
Comment: I think there isn't a difference, they seem to by synonymous, according to the dictionaries I checked.
Comment: synergetic [ˌsɪnəˈdʒɛtɪk], synergistic *adj* another word for synergistic http://www.thefreedictionary.com/synergetic
Comment: 'synergetic' sounds like someone was trying to remember 'synergistic' but made up their own way of making an adjective out of 'synergy'. It sounds 'off', so the more likely one you would use in most formal contexts is 'synergistic'. But maybe some groups particularly like the other one.
Answer: Other than synergistic having some specialized meanings in theology and medicine, both have the same definition as per the OED. Synergistic is the older of the two and, at least in my experience, more common.
Comment: *as per* is the standard expression in parts of the world outside the US. ***as per*** Consistent, or in accordance, with. en.wiktionary.org/wiki/as_per
Comment: What does "as per" say in your sentence above that "per" alone does not?  Isn't "as per" a bit too much?
Answer: Synergistic is older and is still used scientifically in many fields. It usually means that there is a proven result that is more than the sum of its parts. I would use this term if there are corroborating results. Synergetic is newer and is most often used in coaching for productivity in work groups. It usually implies the intent and determination to produce better outcomes working in synergy with others, regardless of success.


Storing Sha256 Hashed Passwords with Nhibernate

Question: I have a simple web app that has a login page, the front end domain has a simple model with:
string username {get;set;}
string password {get;set;}

However it is encrypted with sha256 before it is sent over to the data domain object, originally the data domain was:
string username {get;set;}
string password {get;set;}

So I would take the password from the ui, encrypt it then using the Encoding.GetString() method, get back a string for persisting. However when I try to persist the data it just seems to give an exception, which I believe to be down to the characters in the string not being valid.
After looking around some people have recommended storing it as a varbinary(32) and using a byte[] password {get;set;} within the data layer, however I couldn't get Nhibernate to map it correctly.
So can anyone tell me the best practise on storing hashed passwords with Nhibernate and SqlServer or MySql. (The app supports both dbs)
Answer: You shouldn't use Encoding.GetString() on a SHA value since it will produce text that may not store correctly, or worse, give an exception. Rather use something like Convert.ToBase64String.
Comment: I assumed that, as I think I mentioned above with it not storing. Hence the question on what is best practise to deal with these hashes...


Half a donkey intuition? What does that mean?

Question: In Michael Ende's novel The Neverending Story, the character Yikka, a talking mule, keeps saying that her intuition comes from being "half an ass (donkey)." "When one is only half an ass, and not a whole one, one knows things." I don't have a German translation of the book to get the original phrase, but... is there something in German language or culture that explains this line? She uses it as an explanation of how she was able to sense the identity of a stranger, and how she sometimes knows what her human rider is thinking. ???
Answer: In German it is

Wenn man bloß ein halber Esel ist wie ich und kein ganzer, dann fühlt man so was.

This is a somewhat mysterious statement and there is nothing in German language or culture that explains it. I think one can only make conjectures about its meaning.

Naive explanation.

The word "Esel" (donkey) is often used as synonym for a fool. Perhaps this is the reason why the translator used the word "ass" instead of "donkey". This could mean that Yikka wants to say that she is not foolish enough to ignore the truth.

Psychological explanation. See Gronemann, Helmut: Phantásien – Das Reich des Unbewussten. "Die unendliche Geschichte" von Michael Ende aus der Sicht der Tiefenpsychologie. Zürich: Schweizer Spiegel Verlag 1985. Also see here p. 79.

Nach Ansicht Helmut Gronemanns versinnbildlicht der Esel das Unbewusste, das Pferd dagegen verkörpert das Bewusstsein. Das Gespür des Maultieres besteht demnach in der Fähigkeit, beide psychischen Komponenten zu vereinigen. Das höhere Wissen des Tieres versinnbildlicht so die Geschlossenheit, die Bastian erst erreichen muss.
Translation via DeepL:
According to Helmut Gronemann, the donkey symbolizes the unconscious, while the horse embodies the conscious. The sense of the mule thus consists in the ability to unite both psychic components. The higher knowledge of the animal thus symbolizes the unity that Bastian must first achieve.
By the way, here is the German text.
Comment: I go with the naive explanation because it shows that the mule is cunning.
Answer: To be honest, this question is subject to interpretation...
But I'll give it a try. Since Yakka is a mule, she is technically half an ass and not a full one. I think Ende plays with different attributes, the word "Esel" (ass) and the animal have in German language and culture:

The word "Esel" is often used to describe a human being as very stupid. Therefore, the "whole ass" would not be able to feel the things Yakka feels

On the other hand, donkeys are often considered wiser then humans in Germany (and maybe in other countries) when it comes to feel danger, finding the right way and so on. The fact that donkeys sometimes refuse to follow orders from given by humans is often explained by saying that they are able to see/feel something humans cannot see/feel

So I think, Ende wants to say that Yakka has the wisdom of a donky without being "a whole ass".


How to to Use a Nylon Shoulder Washer?

Question: I'm somewhat curious as to how to use a nylon shoulder washer with a bolt. There is an example of this here (https://electronics.stackexchange.com/a/45579/95654), but I can't figure out how it would stay attached to the board. The diagram does not imply that the washer is threaded, so the hole is large enough to fit the washer (without any teeth to hold it) and ensure that the bolt does not close any circuits, but then how does it not fall out if it was inverted/sideways? Even if there was a nut at the bottom of the bolt, I still can't see how it would be stable.
Answer: Using the schematic option produces ugly results, but I hope the following diagram will help.

simulate this circuit – Schematic created using CircuitLab
It shows a bolt passing through a single layer of material, with a sholder washer on each side, and a nut, all in cross-section. When the nut is threaded onto the bolt, the washers are held in place.
Answer:
(source: Heatsink mounting kit)
The shoulder washer is intended for bolting a TO-220 to a heatsink (or some other metal part) while maintaining electrical isolation with the heatsink.  There is usually a nut on the other side of the heatsink, or the screw hole is threaded.
If you are attaching the TO-220 to a part of your PCB that has no traces, then you don't necessarily need the shoulder washer.  The PCB material under the TO-220 would act as an isolator.
Answer: I'm on my phone, so I can't link to a website that might show a picture.
A Shoulder Washer is normally used in conjunction with either a flat washer (thin material) or another shoulder washer (thick material).
The hole through the material is very slightly larger than the diameter of the raised part of the shoulder washer. This shoulder keeps the washer centered in the hole.
The most common use that I have had for shoulder washers is when mounting power transistors to a heatsink or metal chassis.
Comment: Yes, I understand that the ring around the neck of the washer is resting around the hole. In other words, it can't fall through. However, if the board is inverted, how is it going to stay if it does not have threading?
Comment: you usually have a nut on the other side, probably with its own washer

How to to Use a Nylon Shoulder Washer?


FB Login : Don't know how to get response after a successful login

Question: I have added an fblogin button to my website
it is working fine
a button is placed and when user clicks on it a dialogue box opens for login.
But i don't know how to get response after a successful login.
Please suggest
Answer: You can use the JS SDK to subscribe to events of that type. Take a look at the facebook javascript documentation, the method you are looking for is 'auth.authResponseChange'  :
FB.Event.subscribe('auth.authResponseChange', function(response) {
  alert('The status of the session is: ' + response.status);
});


How to run basic OpenCL face detection code

Question: I tried running the OpenCL basic face detector code which is in "samples/ocl/facedetect.cpp". Before compiling the face detect code I followed the below steps to compile OpenCV with OpenCL enabled.

I downloaded OpenCL SDK by Intel from Intel SDK for OpenCL Applications 2013 and installed it.
Using CMake, I enabled "WITH_OPENCL" and built OpenCV successfully. The "libopencv_ocl245.dll" got created.

I tried compiling the face detection code and it compiled successfully. But int devnums = cv::ocl::getDevice(oclinfo, ocl::CVCL_DEVICE_TYPE_DEFAULT); always returns "0".
I changed the following flag, and I got the below error:
Flag:

int devnums = cv::ocl::getDevice(oclinfo,
  ocl::CVCL_DEVICE_TYPE_DEFAULT);

Error:
>     0x06670A02 (0x08730080 0x00000000 0x00000018 0x0A3121D8)0x06670A02 (0x08F70080 0x00000000 0x00000024 0x0A0DC008)0x06670A02 (0x097B0080
> 0x00000000 0x00000000 0x0028E48C) <unknownmodule>
>                                                                                <unknown module>
>                                                                                0x630E6900 (0x0A3121C8 0x00000000 0x00000000 0x00000018)0x630E6900
> (0x0A0DBFF8 0x00000000 0x00000000 0x00000024) <unknown module>
>                                                                                0x630E6900 (0x0028E47C 0x00000000 0x00000000 0x00000000),
> opencl_mic_printf() + 0x12130 bytes(s), opencl_mic_printf() + 0x12130
> bytes(s), opencl_mic_printf() + 0x12130 bytes(s)  ....

Is there any hardware dependency for running OpenCL face detection code? I am running the code on an Intel CPU.
What are the specifications needed to run the OpenCL face detection sample code?
Am I wrong anywhere in the above steps?
Is only installing the OpenCL SDK enough? Or do I need to install something else?
Answer: You are possibly using OpenCL 1.1 instead of 1.2. Or perhaps an Intel CPU that is only compatible with OpenCL 1.1. OpenCV needs the OpenCL 1.2 files and an OpenCL 1.2 compatible device to run.
Judging by the fact that your using an Intel CPU, I'm probably going to be wrong on this answer since most Intel CPUs would be compatible with OpenCL 1.2, but it's worth a look. Another possibility is that your default OpenCL device is your GPU, which if it's from Nvidia, probably isn't compatible with OpenCL 1.2.


How to stop cloth-physics from catching on pointy surfaces?

Question: I'm using cloth because soft-body is too slow. As a test I have a character's hand pushing against a zero-gravity cloth surface with high structural integrity, but the when the character pulls back, the drag of the cloth causes it to catch on their fingers and twists and wraps around before falling off. What setting can I modify to stop this from happening? Part of the problem is the hand pokes through the cloth and I don't know how to prevent that either. Subdividing the cloth somehow makes the problem worse.
Answer: Most of these come with larger simulation times, try to keep the subdivision to a minimum.

Increase the substeps of the simulation to prevent the geometries from ever intersecting.
Increase the quality of the collision with the Quality slider.
Increase the (minimum) Distance of the collision. Note that this will also create a gap between the object. I would advise to simulate with an offset animated collider, which can be repositioned after baking.
Replace the animated object with simpler geometry. Recreate the basic shape with concave meshes, with evenly distributed triangles while trying to keep the edge angle at a minimum. Hide these helper collision for rendering.
Comment: @AskingRandomQuestions If an answer helped you in some way upvote it so it may help others in the future. If you feel it completely solved your problem consider marking it accepted
Comment: Is there a way to use a kind of proxy mesh for calculating cloth deformations? Or would that just make it more complicated?
Comment: That's what I meant with (4). Use a proxy mesh. Concave, small angles, low poly, non-deform if possible.
Comment: I don't know yet if it helped yet. I tried a few steps and it didn't help much.


How to make Wordpress Category menu items display the category as title?

Question: I have been looking for this function everywhere but cannot seem to find a clear way to do it.
I have created a blog with a category-based menu but I was wondering how I could get the menu item to display its category as a title whenever it is clicked. I need this because on my website I have post items which share the same category therefore I need to be able to tell the user of his/her location. Once the user clicks on the post however, it is the first category which will be displayed as a title and this seems to be working with:
<code>$category = get_the_category();
echo $category[0]->cat_name;
</code>
The only time that this is a problem is when the posts that share the categories do not have their main category listed first.
I hope that I am making myself clear,
Thanks.
Comment: Can you maybe give us a link to see what's the issue?
Answer: You can look at the category slug in the URL, and get the category by its slug.
<code>$cat = get_category_by_slug( $slug );
echo $cat->name;
</code>
http://codex.wordpress.org/Function_Reference/get_category_by_slug


Layers in physics or what is it (look at the image)?

Question:
I need to move an object on track when obj getting into track, but at the same time, it could easily pass under it.
I don't know how it called. And I'm looking for name of this procedure.
Answer: From what I know there is no simple way of making one object collide with another and later to suppress this behavior.
I suggest re-creating this part of a track with categoryBits, maskBits set accordingly (or isSensor=true flag to turn off the collisions with this object) when the vehicle changes its virtual altitude.
http://developer.coronalabs.com/content/game-edition-collision-detection
Answer: If you are using physics to detect the collision you could just remove the object (train, car, ball, what ever is supposed to go under the track) from physics to avoid a collision and then re-add it once you the object passes under the track.
Answer: Just set the order of your object displaying. As far as I know the order in which variables are declared sets up who takes precedence over the other.
For setting up the collision (in order to avoid hitting each other) just use the categoryBits and maskBits.
Answer: As atok said, I'm pretty sure that there isn't any way to set collision masks after you've called physics.addBody() on a DisplayObject.
There's a wonderful guide on collision filters (using categoryBits and maskBits) here, and the docs for physics.addBody are here. There's also some other stuff on it here.


SWTOR Launch Problems

Question: Every time I press the play button on the launch screen, the launcher closes but the game never shows up. I've tried all the things Bio-ware suggested. I've even tried some of the stuff other people have suggested to no avail. What should I do?
Comment: Have you updated the game? Can you start with the lowest graphic settings? What OS are you using?
Answer: This has worked for me on several installs:

Add launcher.exe, fixlauncher.exe, and swtor.exe to your antivirus and firewall whitelists.
Configure all 3 to run as Administrator and compatibility mode for the next lowest Windows version — i.e., Windows 7 SP1 if you're running Windows 8/8.1. You do this in Properties for the executable.
Reboot.
Run FixLauncher.
Run the launcher.  Leave it while it updates and restarts itself.
Login and play!

SWTOR Launch Problems


Can't change any settings

Question: When I open my session, the wallpaper changed to the default one and I can't change any settings. When it happened for the first time I was running on Ubuntu 13.10, I have upgraded to 14.04 LTS hoping that it would fix the problem, but unfortunately it didn't.
Comment: Where is your desktop wallpaper located? What do you mean you can't change any settings?
Answer: I fixed the problem by deleting the .cache .compiz and .config folders from my home folder.
Comment: Just to confirm that this works. I had the same issue (not being able to change any user settings and few other annoyances). I spent almost entire day trying various things with no success. Deleting .config and .cache folders magically repairs everything. Thank you man..
Comment: I love you so much!
Answer: When I encountered this issue it turned out I mistakenly changed the ownership of the "user" file in /home/{my user}/.config/dconf/. Changing the ownership of /home/{my user}/.config/dconf/user back to {myuser}:{my user} fixed the issue, e. g.:
sudo chown dennis:dennis /home/dennis/.config/dconf/user

I figured out where the issue was by tailing /home/{my user}/.cache/upstart/unity-settings-daemon.log while trying to change settings.
(unity-settings-daemon:2157): dconf-WARNING **: failed to commit changes to dconf: GDBus.Error:org.gtk.GDBus.UnmappedGError.Quark._g_2dfile_2derror_2dquark.Code2: Cannot open dconf database: Failed to open file '/home/dennis/.config/dconf/user': Permission denied

Can't change any settings


Get CMYK values from image, change them, and save as new image - C++

Question: I need to load 8bit Tiff CMYK image at pixel level for image manipulation. Idea is to be able to change loaded C M Y K pixel components and save changes to new CMYK Tiff file. My question is how can this be done in c++, and which library is easy to use (installation process and API). I'm new to c++, but programming isnt new to me (hobby, but now I need it for student research). Its just more confusing to work in c++ compared to other languages, like Python for instance. So to repeat my question once more, how to do image manipulation for 8bit Tiff CMYK at pixel level with being able to change CMYK components for each pixel in c++, and please can you tell me what I need to install to accomplish that(free libraries only because it is for student research)? Can this be done with libraries that are in C++ Visual Studio 2010 express edition?
Thanks!
P.S. I've done all that in Python (manipulations saturation, desaturation, UCA, GCR, UCR) but now I need to do in a compiler language for comparison between two programs. I've tride to do it in c# but that cmyk barrier of not be able to do stuff with cmyk image also appeared.
Answer: Maybe CXImage will help http://www.codeproject.com/KB/graphics/cximage.aspx


France Airport Transit Visa for Indian Passport Holders

Question: I will be traveling from India to Cuba with an connecting flight at Paris CDG airport to Cuba. The layover is 7hrs. Do I need a transit visa for the layover at Paris Airport?
Comment: Are both flights on the same ticket/booking? Do you have checked bags?
Answer: According to Timatic https://www.timaticweb2.com Indian citizens can transit without a visa, providing you meet the following conditions:
" Passengers transiting through Paris (CDG), arriving from a non-Schengen Member State with a confirmed onward ticket for a flight within 24 hours to a third country which is not a Schengen Member State. They must:

stay in the international transit area of the airport, and
have documents required for their next destination."

This means both flights must be on the same ticket/booking (or not have any checked bags), otherwise you'll need a visa to go through passport control to reclaim bags and re-check them.
Comment: @jcaron Thanks, I've amended my answer to include this. Although I think the duplicate you've flagged is probably the preferred answer
Comment: Actually, if they go through passport control they need a full visa, IIRC there are no longer any transit visas in the Schengen Area (except ATVs).


Tracing genealogy in South Africa and prior

Question: What is the best process for tracing a family line from a great-grandfather and upwards in South Africa. What do you do once the line goes outside of South Africa to Netherlands/Germany? Who do you use over there? Are there professionals one can pay to do the hard work, especially in South Africa?
Comment: Welcome to Genealogy.SE!  This question has several different questions in it; it will be easier for others to answer if you post one question per question (see http://meta.stackexchange.com/questions/39223/one-post-with-multiple-questions-or-multiple-posts ).  I will take a crack at answering the 'tracing genealogy in South Africa'.  The topics of research in Germany (or moving between two countries) and hiring a professional might benefit from having their own questions.
Comment: I agree wholeheartedly with @JanMurphy - these are valuable questions but to get the attention they deserve I recommend that each Question contains only one question.
Answer: I'll start with how to trace a lineage in South Africa (leaving the finer points of hiring a professional for another question).
The basic principle of tracing any family line is to start with what you know, and to work backwards or outwards in small steps, working from the known to the unknown.  You've already narrowed the focus of your research to a single family line, one of your great-grandfathers.

Gather whatever information you have which has been passed down in your family.
Make a list of all the sources you have.
Extract from this material events and attributes associated with your great-grandfather, his immediate family, and his friends, associates and neighbors.  (Some people call these events and attributes 'facts', but for all events which we didn't experience ourselves directly, anything we 'know' is actually what someone else said; some genealogists prefer to use the terms 'assertions' instead, to reflect the fact that a person or historical record says that something happened.)
Assemble these events and attributes into a timeline, noting where each assertion comes from.
Write a biographical profile of your great-grandfather, taking into account all of the evidence you have gathered so far.
Make a Research Plan, outlining the information you would like to know.

All of these steps help whether you are doing the work yourself, or hiring someone else -- any researcher you hire will need to have enough information to recognize that they have located the right person, in order to do this work for you.
Here are some basic links for getting started in South African research:

Conrod Mercer's website South African Genealogy
Beginners Guide To South African Research by Rosemary Dixon-Smith, of Mole's Genealogy Blog
Getting Started with South Africa Research from the FamilySearch Wiki (note their link to Rosemary Dixon-Smith's Beginner's Guide is currently broken; as I write this, the link above is working)
The South Africa portal on Cyndi's List


Migrate WordPress blog to Drupal

Question: I'm migrating two blogs from WordPress to Drupal 7. How would one handle migrating user subscriptions from the WordPress blogs? I've already used the Migrate module and it looks like that only handles content.
Answer: You may try using WordPress Migrate which supports migrating WordPress blog exports (WXR format) into Drupal using Migrate module. Check also Migrate Extras which provides additional support for contrib modules.
For any other extra functionality which is not covered, you've to extend it by writing your own custom class. Check Migrate Example for example of migration data.
See also: What is the most reliable way to migrate a Wordpress site into Drupal?

Migrate WordPress blog to Drupal


Is it still possible to get @icloud.com email address?

Question: Set up a new iCloud account for someone and I am not seeing the option to set up an @icloud.com address and use the free email service. Does anyone know if this is still possible and how to go about doing this?
Comment: Does [this](https://support.apple.com/kb/PH2620?locale=en_US) help?
Comment: "If you set up iCloud using an Apple ID that doesn't end with icloud.com, me.com, or mac.com, you must set up an icloud.com email address before you can use iCloud Mail." It doesn't explain *how* to do it.
Comment: I can't do it, which is why I asked if the link helped, but do what the next line after that says... Go to Settings > iCloud and turn the mail switch on, I think that's the point you get to create it
Comment: I see what you mean now, I will try this later and update this thread. I do not remember having to set up mail on the physical device previously.
Comment: Go to [iCloud.com](https://www.icloud.com), and click _"Create Your Now"_.
Comment: Confirmed, I just tried this on someone else's phone.  I'll make it an answer.
Answer: The steps seem strange, but first you must create your appleid using a non Apple address (note that if you already have an @icloud, @mac, or @me email address that email address is already an Apple ID)
Once your Apple ID has been created, on the device go to Settings > iCloud and flip the mail switch on, you will be prompted there to create your @icloud.com email address.
Alternatively, you can go to setting and go to mail. From there, add account and choose iCloud. If you choose "create Apple ID" at this screen, for whatever reason, it will allow you to create an "@icloud.com" email.
source Apple kb
Comment: I just executed this instructions and they worked.
Answer: Using a Mac:
System Preferences -> Internet Accounts -> (Maybe you need to click the +) -> Select iCloud on the right -> Create Apple ID -> Follow the steps
Also note that after entering your birthday, you should select "Get a free iCloud email address".
Answer: iCloud accounts are different for different devices. If you are using iPhone, iPad or even an iPod Touch you can use iCloud. iCloud is Apple's own icloud service which allows you to save all the data which is present on your iPhone on the online cloud. In order to use iCloud service, you will have to create icloud email address (@icloud.com).
Creating a Free iCloud Email Address (@icloud.com) is really a very simple task and it doesn't take much time.  Here's how to create @icloud.com email address on an iPhone or iPad device:

From the Home screen of your device, select Settings option and tap
on the iCloud button.
If you are already logged in with any iCloud
account then log out.
After logged out, select Sign in to your iPhone
On the screen to enter your Apple ID, select Don't have an Apple ID or forgot it?

Select Create Apple ID
option.

Now, enter your Birthday, First Name and Last Name.
Select Get a free iCloud email address
Now, enter the username which you want to use in your iCloud account.
To set up an @icloud email address confirm the process by selecting the
Create Email Address button.
Enter a Password and confirm too.
Now to secure your iCloud account, you must enter a phone number that can receive a text message or phone call
Enter the verification code you receive via text or phone call
Finally agree to the Terms and Conditions. That's it!
You have just created a free icloud email address. Now enjoy!!

Thus, you can see how simple is to create a free iCloud email address (@icloud.com).
Answer: You can use Apple's iCloud service without creating an @icloud.com email account.   I've had an iCloud account for ten years, and it does not have an @icloud.com email address, or any other apple email address, associated with it. My suggestion is to not even do what you ask.
Comment: I've edited so it so it addresses the answer and not some other comment or question.


Were the ancient Greeks very poor compared to the ancient Persians?

Question: Today, one way modern scholars determine civilization is by it's material prosperity and consumption levels. To be prosperous is for the man of today a good thing and we consider poverty in a nation and the so-called "bare-bones subsistence" to be a mark of the uncivilized. However, this has posed several very important problems for the economic history of the ancient civilizations.
For the Greeks and Romans, the word "luxury" (read: prosperity) was intertwined with "decadence" and "immorality". Indeed, the Greeks never failed to distinguish themselves from the "barbarians" that laid in Asia, who wallowed in luxury and had significantly higher standards of living. For Demosthenes, the poorly made houses of Miltiades and Aristeides signify the nature of the democratic constitution. Herakleides says that you can be certain that you have arrived in Athens when you encounter homes made out of mean material. These are just two examples out of a thousand that are to be found in Greek literature, specially when it comes to "Oriental" luxury that the Greeks were supposedly against.
Plato in Alcibiades for example says: "Again, if you care to consider the wealth of the Persians, the splendor, the clothes and trailing robes, the anointings with myrrh, the throng of servants-in-waiting, and all their other luxuries, you'd be ashamed of your circumstances, because you'd see how inferior they are to theirs." He also further adds that Athens was poor compared to Sparta but nonetheless says "But great as they are when compared with other Greek cities, the Spartan fortunes are nothing compared with the fortunes of the Persians." For Demosthenes and many others, democracy was conducive to poverty and that is why it is to be preferred. Monarchies and oligarchies lead to higher standards of living and that's why they are to be rejected, as Plato himself adds in his wealth of Sparta compared to the poverty of Athens.
The Greeks emphasized everywhere that the Persians were far more prosperous than any Greek ever was, and that this was why Greece was superior to the Persians. In their "othering" of the "Oriental", the Greeks idealized poverty and considered it most beneficial for morality.
The Greeks in their representations of the "Other" emphasized how rich, how wealthy, how prosperous and how significantly higher ways of living that their Asian barbarians had, specifically the Persians. The "poorly made houses" of Athens compared to the glorious houses everywhere in Persia with all their luxurious splendor is why the Athenians are better than the Persians.
The Romans were not better than the Greeks in this matter. For example, Sallust traces the moral decline of Rome by emphasizing the growing wealth of the people and the disappearance of poverty: "As soon as riches came to be held in honour, when glory, dominion and power followed in their train, virtue began to lose its lustre, poverty to be considered a disgrace, blamelessness to be termed malevolence. Therefore as the result of riches, luxury and greed, united with insolence, took possession of our young manhood."
This has posed a rather very problematic conundrum for us moderns: we consider poverty to be something bad and it is something to be removed rather than maintained. Likewise, prosperity is the mark of a civilization. Nobody would take the claim seriously that the Africa is far superior to the West because the Africans are extremely poor.
Therefore, the Greeks in their profuse orientalizing have raised quite a significant issue. Were the Greeks drenched in poverty compared to the Persians? Was democracy really destructive of material prosperity?
Modern economic historians who have attempted to analyze the economic growth of ancient empires have found the claims of Greeks in their literature highly troubling. Ian Morris who attempted to consider the per capita incomes of Athens has likewise emphasized that the claims of rampant poverty through the Greek world compared to the extreme luxury of the Persians is to be taken not seriously. That is, the Greeks took the court of the King as something that the ordinary citizen of Greece is to be compared against.
Has anyone performed any study of economic growth of the Achaemenid Empire and attained any acceptable calculations of the per capita incomes and compared them to that of contemporary Greece? Is there any information available on this matter? Were the Greeks really poor compared to the Persians? Did those in the East truly have far higher standards of living?
I'd like specifically a more economic analysis of this matter. Has any scholar considered the per capita incomes and the consumption levels of Classical Greece and compared them to that of the Persian Empire? Any attempt at solving this problem by merely considering the claims in the literature won't be helpful, since only claims of Greek poverty and Oriental luxury abound.
Comment: On my opinion, this question does not have a meaningful answer. How do you want to compare? By per capita  average yearly income? Including slaves or not? We know neither the gross income nor the population of these entities. The ancient writers probably meant some elites when they made comparisons.
Comment: Concur with @Alex. Democracies are more likely to measure per capita wealth; aristocracies are going to measure wealth through land or other zero sum metrics. Comparing the two will be misleading.  I'd feel better about the question if it included preliminary research to define the terms.
Comment: Per capita wealth is perhaps not a useful measure here, as the Persians probably concentrated wealth in the hands of an aristocracy.  (Which was mostly what the Greeks saw.)
Comment: Is this a question or a novel? Consider shortening your question somewhat.
Comment: It'd be more helpful if you could provide contexts for the various quotes you referred to.
Comment: Who do you mean when you write "the Greeks"? Athenians, Spartans, people in a small village which depends on Athens? Greece was never a country before being united by Philip of Macedonia and his son Alexander.
Comment: *Were the Greeks drenched in poverty compared to the Persians? Was democracy really destructive of material prosperity?* These are two different questions, aren't they? Suppose it turns out true that (1) Classical Greek poleis have some or a lot of political democracy and the Achaemenid Empire has little or none; and also (2) the median polites in a Classical Greek polis has less material wealth than the median subject of the Achaemenid Shah. Even if both (1) and (2) are true, does it follow that (1) is the *cause* of (2)? Couldn't (1) coincide with (2), but (2) be true for unrelated reasons?
Answer: There are certainly scholars who have tried to quantify economic growth and income disparities over the long term, most notably Paul Bairoch and, especially, Angus Maddison. I don't have their books at hand and do not know whether their data goes as far back in the past or if they looked at this specific comparison but as I recall the main finding is that until relatively recently, per capita income did not increase or differ much.
Some land and some cultures (e.g. rice) can support a higher population density and some polities are better at concentrating wealth to their center, natural catastrophes, pandemic or wars could disrupt societies and bring hardship but generally speaking the standards of living were roughly the same (and rather low). That all changed in the last millennium, which saw both a significant increase in prosperity and consumption and a larger gap between regions or countries. Consequently, it's highly unlikely that the Persian would have "far higher" standards of living than the Greeks.
Obviously, that a source would make a point of being disdainful of excess wealth or inequality tells us very little about actual income. More recently, you can see similar tendencies in countries like Denmark or the Netherlands, where it is or was bad taste and uncommon to engage in conspicuous consumption. Yet, they are not poor in any sense of the word. And I am not sure I believe your contention that material wealth is universally revered in the modern world. You can easily find people or communities that value the ability to detach oneself from material possessions or even who despise modern (capitalistic) economies and praise traditional cultures.
Looking beyond historical times, you can even find anthropologists who argue that hunter-gatherers societies were, in some sense, more prosperous than (early) agricultural societies based on the notion that it takes a lot less work in a day to secure (enough) food that way. While agriculture made a huge population growth and wealth concentration possible, it was also for a long time accompanied by widespread food insecurity and regular famines.
Comment: Hunter-gatherer societies are also subject to food insecurity and starvation.  It just tends not to make the history books because hunter-gatherers tend not to record their history.
Comment: @Mark I am sure but the argument (not based on the historical record but on observation of the amount of effort/time it takes to feed a group) is that they were not as close to starvation as agricultural societies have been for most of history. Obviously, the population density sustained on a given area is much smaller. I haven't looked into all this carefully enough to have an opinion but I find the notion intriguing and it certainly belies the notion implicit in the question that there is a universally agreed yardstick of what a prosperous civilization is.
Answer:
Today, one way modern scholars determine civilization is by it's material prosperity and consumption levels. To be prosperous is for the man of today a good thing and we consider poverty in a nation and the so-called "bare-bones subsistence" to be a mark of the uncivilized.

This is a very strong statement which isn't justified by how the ancients saw themselves, and nor how, even today, in a world of rising consumption and material prosperity, how people judge civilisation. For example, the Vizier Rekmire, who was an ancient Egyptian noble and official of the 18th dynasty who served as the governor of Thebes and also as Vizier during the reigns of Thutmosis III and Amenhotep II around 1400 BC had inscribed in his tomb the regulation given to him to act in his capacity as Vizier to Pharoah:

Forget not to judge justice. It is an abomination of the god to show partiality. This is the teaching. Therefore, do you accordingly. Look upon him who is known to you like him who is unknown to you; and him who is near the king like him who is far from his house. Behold, a prince who does this, he shall endure here in this place

and

Behold, when a man is in his office, he acts according to what is commanded him. Behold, the success of a man is that he act according to what is said to him. Make no delay at all in justice, the law of which you know. Behold, it becomes the arrogant that the king should love the timid more than the arrogant!

A similar sentiment is echoed by the Iran Chamber Society about the Ancient Persians:

The strength of Cyrus lay in his own character and in the character of the army he led. His soldiers were accustomed to privations, but they possessed an inner fire. "The Persians are proud, too proud, and they are poor," Croesus said once...they lived simply, and were close to the earth. It had been hammered into them from their earliest childhood that they had only three tasks to perform well in life --to ride well, shoot straight, and speak the truth, by which it was meant that they should speak the true words of the prophet Zarathustra and worship the god Ahuramazda and the other gods. Half-enviously, Herodotus recounts the stern simplicity of their ceremonies; there were no flute-players, no garlands, no pouring of wine. Before worshipping, a Persian would simply stick a spray of myrtle leaves in his headdress. For a few more years this spartan simplicity remained; then, as more plunder fell into their hands, the Persians learned to enjoy magnificence.
Answer: No.
What IS true is that there were greater extremes of wealth and poverty in the Persian empire.
The Greeks were "wealthy" for their time. It's true that their rocky soil was not particularly good for growing food. But the special qualities of the soil made it good for growing two other key crops, grapes for wine and olives for oil. These were high value added commodities that could be traded abroad for food and cloth on favorable terms. These crops also lent themselves well to free, relatively equal and prosperous yeoman farmers working on small plots of land without the benefits of economies of scale.
The Persian empire was exactly the opposite. On one hand, it consisted of 127 provinces, meaning that that the kings and nobles at the top were very wealthy. Far more so than their Greek equivalents. On the other hand, Persian peasants, at the bottom, were exploited to provide for the wealth of those above, meaning that they were worse off than their Greek counterparts.
Because Persia was much larger, it's probable that Persian wealth (GDP) was much greater than that of the Greeks. It's possible that that the Persian "average" was greater than the Greek average if you use the arithmetical "mean." But the "average" (median) Greek was better off than the equivalent Persian.
So the contrast was not between Greek "poverty" and Persian "wealth" but Greek democracy (of near equals) and Persian despotism.
Answer: It is very true that democracy, now thought to make a country richer, made everybody poorer in those days. This is accepted by all Greek writers without exception and without any suspicion. The people under monarchies in the East had extremely high standards of living compared to Ancient Greece. In other words, the civilization of the East was probably more sophisticated in terms of prosperity, healthiness and way of life.
I'll quote Athenaeus on this question, as he contrasts widespread Greek poverty which was worse than even that of Africa today compared to the rich ways of the Persian civilization:

"Concerning the luxury of the Persian kings Xenophon writes thus in
  Agesilaus: "For the benefit of the Persian king they go about the
  entire country in search of something he may like to drink, and
  countless persons devise dishes which he may like to eat. No one could
  say, either, what trouble they give themselves that he may sleep in
  comfort. But Agesilaus, being devoted to hard work, was glad to drink
  anything that was before him, and was glad to eat whatever came first
  to hand, and any place was satisfactory to him for securing grateful
  sleep." In the work entitled Hieron, speaking of what food is prepared
  for the delectation of tyrants and of men in private station, he says:
  " 'I know too, Simonides, that most persons infer that we eat and
  drink with greater zest than ordinary people from this fact, that they
  would themselves, as they believe, be more pleased to dine on the meal
  that is set before us than on what is served to themselves.
For it is anything that transcends the usual that gives pleasure,
  which is the reason why all men except tyrants look forward with joy
  to holiday feasts. For since the tables set before tyrants are always
  heavily laden, they have nothing special to offer on feast-days, so
  that here is the first particular in which they are at a disadvantage
  compared with men in private station, namely in the delight of
  anticipation. Then secondly, he said, I am sure that you have learned
  that the more abundantly one is supplied with things which go beyond
  his needs, the more quickly he suffers from satiety as regards eating.
Theophrastus, in his treatise On Monarchy dedicated to Cassander (if
  the work is authentic; for many declare that it is by Sosibius, for
  whom the poet Callimachus wrote a congratulatory poem in elegiac
  verse), says that Persian kings, to gratify their love of luxury,
  offer a large sum of money as a reward for all who invent a new
  pleasure. And Theopompus, in the thirty-fifth book of his Histories,51
  says that whenever the Paphlagonian prince Thys dined, he had a
  hundred do everything prepared for the table, beginning with oxen; and
  even when he was carried away a captive to the Persian king's court
  and kept under guard,
he again had the same number served to him, and lived on a splendid
  scale. Wherefore, when Artaxerxes heard of it, he said that it was
  plain to him that Thys was living as though he had made up his mind to
  die soon. 145 The same Theopompus, in the fourteenth book of his
  History of Philip,52 says that "whenever the Great King visits any of
  his subjects, twenty and sometimes thirty talents are expended on his
  dinner; others even spend much more. For the dinner, like the tribute,
  has from ancient times been imposed upon all cities in proportion to
  their population."
Heracleides of Cumae, author of the Persian History,53 writes, in the
  second book of the work entitled Equipment: B "All who attend upon the
  Persian kings when they dine first bathe themselves  p163 and then
  serve in white clothes, and spend nearly half the day on preparations
  for the dinner. Of those who are invited to eat with the king, some
  dine outdoors, in full sight of anyone who wishes to look on; others
  dine indoors in the king's company. Yet even these do not eat in his
  presence, for there are two rooms opposite each other, in one of which
  the king has his meal, in the other his invited guests. The king can
  see them through the curtain at the door, but they cannot see him. C
  Sometimes, however, on the occasion of a public holiday, all dine in a
  single room with the king, in the great hall. And whenever the king
  commands a symposium54 (which he does often), he has about a dozen
  companions at the drinking. When they have finished dinner, that is,
  the king by himself, the guests in the other room, these
  fellow-drinkers are summoned by one of the eunuchs; and entering they
  drink with him, though even they do not have the same wine; moreover,
  they sit on the floor, while he reclines on a couch supported by feet
  of gold; D and they depart after having drunk to excess. In most cases
  the king breakfasts and dines alone, but sometimes his wife and some
  of his sons dine with him. And throughout the dinner his concubines
  sing and play the lyre; one of them is the soloist,55 the others sing
  in chorus. And so, Heracleides continues, the 'king's dinner,' as it
  is called, will appear prodigal to one who merely hears about it, but
  when one examines it carefully it will be found to have been got up
  with economy  p165 and even with parsimony; E and the same is true of
  the dinners among other Persians in high station. For one thousand
  animals are slaughtered daily for the king; these comprise horses,
  camels, oxen, asses, deer, and most of the smaller animals; many birds
  also are consumed, including Arabian ostriches — and the creature is
  large — geese, and cocks. And of all these only moderate portions are
  served to each of the king's guests, and each of them may carry home
  whatever he leaves untouched at the meal. F But the greater part of
  these meats and other foods are taken out into the courtyard for the
  body-guard and light-armed troopers maintained by the king; there they
  divide all the half-eaten56 remnants of meat and bread and share them
  in equal portions. Just as hired soldiers in Greece receive their
  wages in money, so these men receive food from the king in requital
  for services. Similarly among other Persians of high rank, all the
  food is served on the table at one and the same time; but when their
  guests have done eating, whatever is left from the table, consisting
  chiefly of meat and bread, is given by the officer in charge of the
  table to each of the slaves; this they take and so obtain their daily
  food. 146 Hence the most highly honoured of the king's guests go to
  court only for breakfast; for they beg to be excused in order that
  they may not be required to go twice, but may be able to entertain
  their own guests."
Herodotus, in the seventh book, says57 that those  p167 Greeks who
  received the king and entertained Xerxes at dinner were reduced to
  such dire distress that they lost house and home. On one occasion,
  when the Thasians, to save the towns belonging to them on the
  mainland, received and entertained the army of Xerxes, B four hundred
  talents in silver were expended in their behalf by Antipater, a
  prominent citizen; for cups and mixing bowls of silver and gold were
  furnished at table, and after the dinner (these were carried off as
  spoil by the Persians). If Xerxes had eaten there twice, taking
  breakfast as well as dinner, the cities would have been utterly
  ruined." And in the ninth book, also, of his Histories58 he says: "The
  Great King gives a royal banquet which is held once a year on his
  birthday. The name given to the dinner in Persian, is tukta, which in
  Greek means 'complete.' On that day alone the king smears his head
  with ointment and gives presents to the Persians." C Alexander the
  Great, every time he dined with his friends, according to Ephippus of
  Olynthus, in the book59 which describes the demise of Alexander and
  Hephaestion, spent one hundred minas,60 there being perhaps sixty or
  seventy friends at dinner. But the Persian king, as Ctesias61 and
  Dinon62 (in his Persian History) say, used to dine in company with
  15,000 men, and four hundred talents63 were expended on the dinner. D
  This amounts, in  p169 the coinage of Italy, to 2,400,000 denarii,
  which, divided among 15,000 men, make 160 denarii, Italic currency,
  for each man. Consequently it comes to the same sum as that spent by
  Alexander, which was one hundred minas, as Ephippus related. But
  Menander, in The Carouse,64 reckons the expense of the largest banquet
  at a talent only when he says: "So then, our prosperity accords not
  with the way in which we offer sacrifice. For though to the gods I
  bring an offering of E a tiny sheep bought for ten drachmas, and glad
  I am to get it so cheap; but for flute-girls and perfume, harp-girls,
  Mendean and Thasian wine, eels, cheese, and honey, the cost is almost
  a talent; and whereas by analogy it is . . ." He evidently mentions a
  talent as though it were an extravagant expenditure. Again, in The
  Peevish Man,65 he has the following: "So burglars sacrifice: they
  bring chests and wine-jars, not for the gods' sake, but for their own.
  The frankincense is required by religion, and so is the meal-cake; F
  the god gets this, offered entire on the fire. But they, after giving
  the end of the spine and the gall-bladder to the gods — because unfit
  to eat — gulp down the rest themselves."
Philoxenus of Cythera, in the poem entitled The Banquet (granting that
  it is he and not the Leucadian Philoxenus, who was mentioned by the
  comic poet Plato in Phaon),66 describes the arrangements of a  p171
  dinner in these terms:67 "And slaves twain brought unto us a table
  with well-oiled face, 147 another for others, while other henchmen
  bore a third, until they filled the chamber. The tables glistened in
  the rays of the high-swinging lamps, freighted with trenchers and
  condiments delectable in cruets, full . . . and luxuriant in divers
  artful inventions to pleasure life, tempting lures of the spirit. Some
  slaves set beside us snowy-topped barley-cakes in baskets, while
  others (brought in loaves of wheat). After them first came not an
  ordinary tureen, my love, but a riveted vessel of huge size; . . . a
  glistening dish of eels to break our fast, full of conger-faced
  morsels that would delight a god. After this another pot of the same
  size came in, and a soused ray of perfect roundness. B There were
  small kettles, one containing some meat of a shark, another a
  sting-ray. Another rich dish there was, made of squid and sepia-polyps
  with soft tentacles. After this came a grey mullet hot from its
  contact with fire, the whole as large as the table, exhaling spirals
  of steam. After it came breaded squid, my friend, and crooked prawns
  done brown. C Following these we had flower-leaved cakes and fresh
  confections spiced, puff-cakes of wheat  p173 with frosting, large as
  the pot. This is called the 'navel of the feast' by you and me, I
  ween. Last there came — the gods are my witnesses — a monstrous slice
  of tunny, baked hot, from over the sea where it was carved with knives
  from the meatiest part of the belly. Were it ours ever to assist at
  the task, great would be our joy. Yet even where we were wanting, the
  feast was complete. Where it is possible to tell the full tale, my
  powers still hold, and yet no one could recount truly to you all the
  dishes that came before us. I nearly missed a hot entrail, D after
  which came in the intestine of a home-bred pig, a chine, and a rump
  with hot dumplings. And the slave set before us the head, boiled
  whole, and split in two, of a milk-fed kid all steaming; then boiled
  meat-ends, and with them skin-white ribs, snouts, head, feet, and a
  tenderloin spiced with silphium. And other meats there were, of kid
  and lamb, boiled and roast, and sweetest morsel of underdone entrails
  from kids and lambs mixed, E such as the gods love, and you, my love,
  would gladly eat. Afterwards there was jugged hare, and young
  cockerels, and many hot portions of partridges and ring-doves were now
  lavishly laid beside us. Loaves  p175 of bread there were, light and
  nicely folded; and companioning these there came in also yellow honey
  and curds, and as for the cheese — every one would avow that it was
  tender, and I too thought so. And when, by this time, we comrades had
  reached our fill of food and drink, the thralls removed the viands,
  and boys poured water over our hands."
Socrates of Rhodes, in the third book of the Civil War,68 describes
  the banquet given by Cleopatra, the last queen of Egypt, F who married
  the Roman general, Antony, in Cilicia. His words are: "Meeting Antony
  in Cilicia, Cleopatra arranged in his honour a royal symposium, in
  which the service was entirely of gold and jewelled vessels made with
  exquisite art; even the walls, says Socrates, were hung with
  tapestries made of purple and gold threads. And having spread twelve
  triclinia, Cleopatra invited Antony and his chosen friends. 148 He was
  overwhelmed with the richness of the display; but she quietly smiled
  and said that all these things were a present for him; she also
  invited him to come and dine with her again on the morrow, with his
  friends and his officers. On this occasion she provided an even more
  sumptuous symposium by far, so that she caused the vessels which had
  been used on the first occasion to appear paltry; and once more she
  presented him with these also. As for the officers, each was allowed
  to take away the couch on which he had reclined; even the sideboards,
  as well as the spreads for the couches, were divided among them. And
  when they departed, she furnished litters for the guests of high rank,
  with  p177 bearers, B while for the greater number she provided horses
  gaily caparisoned with silver-plated harness, and for all she sent
  along Aethiopian slaves to carry the torches. On the fourth day she
  distributed fees, amounting to a talent, for the purchase of roses,
  and the floors of the dining-rooms were strewn with them to the depth
  of a cubit,69 in net-like festoons spread over all."
He also records that Antony himself, on a later visit to Athens,
  erected a scaffold in plain sight above the theatre, and roofed with
  green boughs, like the "caves"70 built for Bacchic revels; C on this
  he hung tambourines, fawnskins, and other Dionysiac trinkets of all
  sorts, where he reclined in company with his friends and drank from
  early morning, being entertained by artists summoned from Italy, while
  Greeks from all parts assembled to see the spectacle. "And sometimes,"
  Socrates continues, "he even shifted the place of his revels to the
  top of the Acropolis, while the entire city of Athens was illuminated
  with torches hung from the roofs. And he gave orders that henceforth
  he should be proclaimed as Dionysus throughout all the city." D So,
  too, the Emperor Gaius, who had the cognomen Caligula71 from the
  circumstance that he was born in camp, was named "the new Dionysus,"
  and not only that, but he also assumed the entire garb of Dionysus,
  and made royal progresses and sat in judgement thus arrayed.
Viewing all this, which surpasses what we have, we may well admire
  Greek poverty, having also before our eyes the dinners of the Thebans,
  an  p179 account of which is given by Cleitarchus in the first book of
  his History of Alexander.72 He says that "after the demolition of
  their city by Alexander, E their entire wealth was found to be under
  440 talents; he further says that they were mean-spirited and stingy
  where food was concerned, preparing for their meals mincemeat in
  leaves, and boiled vegetables, anchovies, and other small fish,
  sausages, beef-ribs, and pease-porridge. With these, Attaginus, the
  son of Phrynon, entertained Mardonius together with fifty other
  Persians, and Herodotus says in the ninth book73 that Attaginus was
  well supplied with riches. F I believe that they could not have won
  the battle, and that the Greeks need not have met them in battle-array
  at Plataeae, seeing that they already had been done to death by such
  food."
Comment: ***"I'd like specifically a more economic analysis of this matter.** Has any scholar considered the per capita incomes and the consumption levels of Classical Greece and compared them to that of the Persian Empire? **Any attempt at solving this problem by merely considering the claims in the literature won't be helpful, since only claims of Greek poverty and Oriental luxury abound**."*
Comment: It's unclear whether the asker is asking about the average person (slaves included) , free men/citizens only,  "civilized" city dwellers or the rulers/ administration
Since your quotes seem to refer to the rulers
the phrase "It is very true that democracy, now thought to make a country richer, made everybody poorer in those days. "   isn't really relevant and should probably be removed
further these example do not portray the Greeks as "poor"  but rather living "without excess"  as preached by Solon of Athens embodied by Sparta, Alexander etc
Comment: Please use correct formatting to enclose quoted material, properly distinguishing your work from that of others.
Comment: @justCal: Please fix the formatting for me.


How do I control the robotic arm motion?

Question: I have a Robotic arm mounted on a car. There's a camera attached to it. Suppose the camera takes the image of a room, and finds that there's something, say an object, that has to be picked up. Say it's 50 feet away from the robot. My question is that how will the robot reach the object in the first place, and secondly, when it has reached the object, how will it know the real world co-ordinates of the object, to pick the object up, using inverse kinematic equations. Any help would be appreciated. Thanks
Comment: Welcome to Robotics.SE! Your question is very very broad. All the things you mention by the way: "_the robot senses that there is something_", "_makes the decision that the 'something' should be picked up_", "_calculates the distance of 50 feet_", "_moving the robot_", "_moving the robot to the found position_", "_moving a robotic arm with IK_" each of them fills entire rooms of libraries with books on how to do it, because they are huge fields of research on their own. Please be more specific.
Comment: Yes, please break this into *at least* 2 questions.  (mobile robot navigation, and object pose detection).  Do a little research on your own first, then come back when you get stuck and have more specific questions.
Comment: "the real world co-ordinates" which world??
Comment: I've tried to ask only a part of the question here https://robotics.stackexchange.com/questions/7682/object-grasping-robot-arm-control. Any help would be appreciated
Answer: With your question, i assume that you are new to this field. This cannot be solved with one concept.
The mentioned objective requires SLAM technique - Simultaneous localization and mapping .
Using SLAM, the robot can be navigated to any location. A camera is not enough to map an area or a room in your case. You also require depth sensors such as kinect or Zed.
You need to develop a program to reach the object for your robot, depending on the architecture that you are using. Here comes the role of a platform.
A typical arduino, or a raspberry pi single board computer is enough for your project. You should be very familiar with these platforms to integrate your sensors and play with them.
Finally, once the location is reached and the object is recognized by the sensors, Here comes the Inverse kinematics into the action.
There is no such thing called "real-world co-ordinates", until and unless you are dealing with GPS for long range SLAM.
In your case,  the co-ordinates of the object are measured in the context of the location of the sensor mounted on your car.
Once the parameters of the object are known, you can use IK(inverse kinematics) for your robotic arm to grab it from its position. (Assuming that you know about IK, as you have mentioned in the question)
Comment: "_You need to develop a program to reach the object for your robot_" isn't very helpful.
Comment: i meant, it is one of the things to do after mounting sensors depending on his architecture, I cannot be more specific for this broad question.
Comment: @Trinadhvenna, I don't believe the OP needs SLAM. The problem is not to localize the robot in an unknown environment. The problem is to search and detect an object and moves toward it.


How to have retractable limbs

Question: I'm sure there are obvious tutorials for this but I didn't know how or what to google exactly so I'm asking here. How would I create and rig an object that has a limb or another piece of geometry that is normally hidden but that can extend from the object? I'd eventually like to have a perfect sphere most of the time but have the ability for the sphere to extrude hands and legs and have them function as a normal rig. I've attached a before and after cube, the after representing the arms and hands.
Comment: Related https://blender.stackexchange.com/questions/89251/how-can-i-rig-telescopic-parts-to-move-one-at-a-time
Answer: You could create your robot's basic armature, with all its limbs out. Parent the limbs bones to the body bone. When you'll parent the object to the armature, use the With Empty Groups mode then in Object Data > Vertex Groups assign each part of the mesh to the group it is supposed to be part of.

Then in the Pose Library save the basic pose and save a second pose that will be the contracted pose, here I've scaled my bones on the X axis. Click on the "+" button to save a pose:

Now whenever you want you can recall the contracted pose (select it and click on the magnifying glass icon of the Pose Library) and keyframe it in the Dope Sheet:

How to have retractable limbs


does workflows work on cross objects?

Question: Does workflows works on cross objects? I have a custom object having a picklist value and another standard object Accounts.If I update the picklist on custom object,it is possible to update the picklist on standard object with a particular value.I tried to use workflows but I think it is not possible.I alos tried to use process builder but that didn't work. Should I use trigger in this case?
Answer: You can not update parent or child record using Workflow but, using Process builder you can do this. Below steps are for child record update using process builder but similarly you can update parent record as well.

The Process Builder allows you to update child records whenever the
  parent record is modified. Here's how:

Create a new Process.
Select the Object.
Define the Criteria.
In "Immediate Action," select Update Records.
Click on the "Object" drop down.
In "Find a field," look for the child object name you want to update.
If child object is a Custom Object the name would contain "__r" at the end.
Select the Child Object name, and then click Save.
In "Set Object Variables" portion, define the field that you want to update in child records.
Click Save.

Similar steps can be used to update lookup fields using process
  builder too.
Comment: Look at the image in answer in *Record* label I have selected `[Contact].AccountId`. You would see `[CustomObjectName__c].Account__c` or the name of lookup field `[CustomObjectName__c].AccountLookupField__c`. Then in last section you would be able to see All Account fields. I have selecte `Account Type` there. @kunalgupta
Comment: Thanks Ashwani,Thanks for your help.I tried to update values on account object which is a parent object  but I could not find the 'type' field which is a picklist anywhere. Basically I want to change the type field value on account object which is a picklist when there is change in service status picklist field on a custom object.
Comment: It has Label `Account Type` @kunalgupta
Comment: Hi Aswani,I seached for Account type and type both but there isn't any field

does workflows work on cross objects?


Google Cloud SQL connection error

Question: I am new to Google App engine and I have tried to run an demo application called guestbook to connect to Google cloud sql from the Google app engine with app-engine-sdk version 1-7.0. But each time I am getting an error  saying "java.lang.IllegalStateException: System property rdbms.driver must be set at com.google.appengine.api.rdbms.dev.LocalRdbmsServiceLocalDriver.registerDriver(LocalRdbmsServiceLocalDriver.java:80)". I double check my code and every thing looks ok, and I still have no glue where the error coming from.
Below is a snippet of my connection code :
c = DriverManager.getConnection("jdbc:google:rdbms://my_instance/my_database");
and mysql-connector-java-5.1.21-bin is in the class path,
and I have enable Google cloud sql in the Google app engine,
and I have checked the use of Google Cloud instance in the app engine as well with the my instance of the database, database name, login , and password,
and I am using Eclipse Juno.
I think I have missed something important; so would you please help me if you know what I have missed.
Thank you very much in advance,
Minh
Answer: Once you are new to GAE I recommend to give a try on the Big Table database. Using it you will not have to setup any database localy. So just the eclipse plugin will be enough for your first test. The Guestbook uses this database so it will be easier to follow the tutorial.

Google Cloud SQL connection error


Wordpress keeps truncating my feeds and I can't stop it

Question: I have a little problem with my self hosted wordpress blog.
the problem is it keeps truncating my feeds even when I have chosen not to in the settings page.
one thing to bear in mind is that I use  tag in almost all of my posts. I was wondering if it's because of that or something else?!
any help would be awesome.
thanks
Comment: Do you have any plugins installed that might be touching your feeds?
Comment: @Manzabar I don't think so. I even installed the `Full Text Feed` plugin but it doesn't do any good!
Comment: According to Full Text Feed's homepage, that plugin isn't needed in WordPress 2.5 (and presumably past that). You are running the lastest version of WordPress (3.2.1), right? Also, if you're not sure about plugins altering your feed, consider disabling all of them and then recheck your feed.
Comment: I have disabled all the plugins and still the problem remains.
Answer: Make sure you check the page source of your feed - some browsers will not show the full feed when looking at it raw (as the plain XML file) when using your browser to view http://yourdomain/feed
If you look at the raw source the full text should be found in under the "content" tag - Firefox for example will only show the "title" "link" and "description" but hide the content. IE will show the full feed in the browser.
Also make sure the full feed is set in the wordpress settings
Answer: Could also be something your theme is doing.  Does you theme have an options panel, with an option related to RSS feeds?


How to Handle my Collisions in java

Question: I'm currently making a color switch game. All my obstacles are made out of 4 shapes of a different color. The shapes are in an array with their index being the same index as its color in a array of colors. The player is a ball or Ellipse shape with a color curColor. How do I see if it overlaps shapes with a different color?
Answer: Perhaps using something like a quadtree might be of some use here. By splitting collision detection into two stages, first coarse then fine you don't waste time computing collision between distant objects.
Split your game world up into rectangles and populate with the stationary(?) obstacles. Each time your player ball moves, find what quads in the tree the bounding box of the player intersects with and return obstacles in these quads. With these, use a more precise collision detection method between the two shapes, using color of the shape as a predicate before checking.
It might be worth considering if obstacles are moving and you need to add them to the quad tree every frame anyway, just adding in colored obstacles which are relevant for collision detection.
Answer: If the other shapes are rectangles you could use this to check if a circle intersects with it:
double left  = //rectangle's most left coordinate
double bottom = //rectangle's most bottom coordinate
//etc
double centerX = //player (circle) center X coordinate
double centerY //it's y coord
double radius //radius of the circle

if(((left-centerX)*(left-centerX)+(bottom-centerY)*(bottom-centerY))<radius){
//it is intersecting
}

And then the same for the top and right coords replacing bottom with top, replacing left with (you guessed it) right and replacing < with >.
If the shape is a circle it will be just a little bit more complicated:
double r0 //radius of player
double r1 //radius of shape
double x0 //center X of player
double x1 //center X of shape
double y0 //center Y of player
double y1 //center Y of shape

double DX = x1 - x0;
double DY = y1 - y0;
double D = Math.hypot(DX, DY);
if(D<r0+r1){
//They are intersecting
}

How to Handle my Collisions in java


VNC android app which takes native control of touch as a mouse

Question: I've been trying to install a linux distribution onto my android tablet for some time now and have done so but have recently stumbled upon a problem. When connecting the mouse, naturally the app does not support dragging windows or scrolling or right mouse click. I was wondering if there was any way to have these things supported by any VNC app. Either that or an alternative way to install linux as a rom.
Answer: VNC Viewer from RealVNC is a bit pricey ($9.99) but probably has the best keyboard/mouse support of any VNC app on Android.
Comment: I've tried that one out and yeah I guess that KINDA works... But I am looking for a more native answer (although a great suggestion!). I think I might try and flash some type of linux kernal and see if I just cant go and work on that but I have no clue where to go from there.
Comment: I answer a question on SU, then it gets migrated back here. So much for trying to branch out of Android =P


Variables in calculation of drag coefficient

Question:
Okay, so I looked up drag force equation, and I found that the equation involved the drag coefficient.  Then I looked up the drag coefficient, and the equation for it involved the drag force.  Eventually this loop stopped as I found this section on a Wikipedia page explaining how to find the drag coefficient of a specific shape.  It all makes sense to me, but I don't understand some of the variables they defined to me, specifically the vectors (yes, I know about vectors, unit vectors, and dot products, but that's not what I'm asking).  It might just be the fact that I haven't taken an AP physics class yet, but the variables don't seem to define the magnitudes of n or t.  As well, by the way it's described, it seems î and n have the same direction, which can't be true or the dot product of t*î would be zero.  And yes, I know, Wikipedia isn't always trustworthy 100% of the time (nothing is), but I've found that Wikipedia has, for the most part, provided accurate information regarding math and science.  If you'd like to get a better reference for this topic, links to this Wikipedia page are down below (look in "Blunt and streamlined body flows").  If you know what these terms are supposed to mean, please explain to me.
https://en.wikipedia.org/wiki/Drag_coefficient
Comment: This is a case of paralysis by analysis.  The data that you listed require a lot of MEASUREMENTS before you can calculate a drag coefficient.  It would be much easier to lump all of those measurements into one term (the drag coefficient itself), and set up an experimental procedure whereby you measure the drag force on a specific object, and back-calculate the drag coefficient involved.  In other words, skip all the integrals, and go directly with the value that nature is giving you.
Comment: The equation would be OK if $\mathbf{\hat{i}}$ were the unit vector in the direction of relative motion between the object and the fluid.
Comment: David White- that's not what I was asking for.  My interest is theoretical, not experimental.  I know all the formulas and they're pretty easy to me (definitely much easier than determining the drag coefcicient of every conceivable shape by performing infinity trials.)
Comment: @David White  If you could please just elaborate on the values of t, n, and î, that would be most helpful.  If you need further information I've left a link to the website in the question.  Thank you!
Answer: Here is the way in which you should interpret the different symbols:

$\widehat{\mathbf{i}}$ is the unit vector in the direction of relative motion (of the object relative to the mass of air).
$\mathbf{n}$ is the unit outer normal to the spherical surface.
$\widehat{\mathbf{t}}$ is the director vector of the tangential part of the traction vector, whose magnitude is $T_w$. That is, the tangential part of $\mathbf{\sigma} \cdot \mathbf{n}$, with $\mathbf{\sigma}$ the Cauchy stress tensor. Note that the tangential component of an arbitrary vector $\mathbf{v}$ can be calculated as $\mathbf{v}-\mathbf{n} \cdot \mathbf{v}$.

Notice that the first term is the projection along the direction of motion $\widehat{\mathbf{i}}$ of integral of the normal component of the traction vector (the pressure) over the sphere (the rest of components are zero (on average) due to symmetry). This is the pressure drag.
Similarly, the second term represents the integral of the remaining components, also projected along the direction of motion. This is the friction (or skin) drag, which is due to viscous friction.
Answer: All vectors $\hat{i},\mathbf{t},\mathbf{n}$ are unit vectors.
It is correct that $\mathbf{t}\cdot\hat{i}=0$. The second term on the RHS of the equation is incorrect.
Second term on the RHS is about finding the total force due to shear stress. More correctly they should have begun with the stress tensor $\mathbf{T}$ (having components $T_{ij}$), found the stress vector acting on the surface element with normal $\hat{i}$, viz. $\mathbf{T}(\hat{i})$. Then $\mathbf{t}\cdot\mathbf{T}(\hat{i})$ gives the magnitude of shear stress, which is nothing but the component of the stress vector $\mathbf{T}(\hat{i})$ along a tangential direction $\mathbf{t}$.
Comment: So, this means that n*î=1?
Comment: @MathMachine Yes, although why they have two symbols to denote the same thing I cant say. Why don't you read _Fluid Dynamics_ by Batchelor which is specifically written for applied mathematicians?
Comment: i is the unit vector in the direction of motion, and t is the unit vector in the direction of the shearstress acting on the surface, the wiki page seems to be wrong with the variable definitions.  So t*i is not always 0, and i*n is not always 1.
Answer: 5 years later!!
I think the expression above (from Wikipedia) is highly confusing due to the A (they say "$A$ is the planform area of the body"). BUT the relevant area $A$ completely depends on the type of force! My point of view is that total drag force has two terms: pressure (or form) drag and viscous (or friction or skin) drag, and each one has a reference area, say $A_p$ and $A_\mu$. For the pressure drag, $A_p$ is basically the area of the body projected onto a plane normal to flow (in the direction of flow), whilst $A_\mu$ (reference area for the friction term) is basically the area of the body projected normally to the flow (for an airfoil, that's its horizontal projection). Of course, very often only one of the terms is significant and the other one is neglected.
Thus, what should be added are the drag forces, not the drag coefficients:
$F_{\rm d} = F_{{\rm d},p} + F_{{\rm d},\mu}$,
where:
$F_{{\rm d},p} = \frac{1}{2} c_{{\rm d},p} \,\rho \, U_0^2 A_p \quad$ and
$F_{{\rm d},\mu} = \frac{1}{2} c_{{\rm d},\mu} \,\rho \, U_0^2 A_\mu \quad$
being $U_0$ the velocity of flow (relative to the body) far, at infinity.


Einstein Field equations for the whole universe

Question: Can someone please show the EFE solved for the entire universe. I've heard people say that 'Einstein solved the Einstein equations for the universe and found this'. If I am missing something, what does this statement really imply?
Comment: https://en.wikipedia.org/wiki/Friedmann_equations
Comment: Could you provide a precise quote? Or at least give some hint about the "this" that Einstein supposedly found. Could this statement be refering to ["Einstein's static universe"](https://en.wikipedia.org/wiki/Static_universe)?
Answer: "Equations for the whole universe" were not solved by Einstein. The Universe with her every captivating quirk and je ne sais quoi is impossible to fathom. The only persons who claimed ultimate solution are the fortune tellers and the Wall Street pundits who purportedly can predict tomorrow's SNP 500.
However, when it comes to the coarse-grained approximate solution (assuming that She is homogeneous and isotropic), there are at least four guys (Friedmann–Lemaître–Robertson–Walker) who beat Einstein to the punch. See wiki quotes below:

The Soviet mathematician Alexander Friedmann first derived the main results of the FLRW model in 1922 and 1924. Although the prestigious physics journal Zeitschrift für Physik published his work, it remained relatively unnoticed by his contemporaries. Friedmann was in direct communication with Albert Einstein, who, on behalf of Zeitschrift für Physik, acted as the scientific referee of Friedmann's work. Eventually Einstein acknowledged the correctness of Friedmann's calculations, but failed to appreciate the physical significance of Friedmann's predictions.
Friedmann died in 1925. In 1927, Georges Lemaître, a Belgian priest, astronomer and periodic professor of physics at the Catholic University of Leuven, arrived independently at results similar to those of Friedmann and published them in the Annales de la Société Scientifique de Bruxelles (Annals of the Scientific Society of Brussels).[10] In the face of the observational evidence for the expansion of the universe obtained by Edwin Hubble in the late 1920s, Lemaître's results were noticed in particular by Arthur Eddington, and in 1930–31 Lemaître's paper was translated into English and published in the Monthly Notices of the Royal Astronomical Society.
Howard P. Robertson from the US and Arthur Geoffrey Walker from the UK explored the problem further during the 1930s. In 1935 Robertson and Walker rigorously proved that the FLRW metric is the only one on a spacetime that is spatially homogeneous and isotropic (as noted above, this is a geometric result and is not tied specifically to the equations of general relativity, which were always assumed by Friedmann and Lemaître).

What Einstein did is tweaking (adding and subsequently dropping a constant term) the equation to make the solution palatable.
To make it worse, Einstein was not even the first to write down the correct version of Einstein equation. It's the great mathematician Hilbert who proposed the action of gravity in 1915, prior to the celebrated 1916 paper of Einstein.
Comment: @aRockStr Yes, in principle, the whole universe has a metric.
Comment: *To make it worse, Einstein was not even the first to write down the correct version of Einstein equation. It's the great mathematician Hilbert.* - There's still some debate about that, based on the discovery that Hilbert's paper went through some revisions...
Comment: Is asking for a solution to the EFEs for the entire universe analogous to asking for a wavefunction for the entire universe? In principle, there exists a wavefunction for the universe but it'd be far to complicated to write down. Instead, we consider small subsystems for which we can write down a wavefunction, such as an atom. Of course, we can write down metrics for black holes and stars and even patch them together with junction conditions. But is there in principle a metric which describes the entire universe, or is that too much to ask of the EFEs?


Is it possible for a language to have mixed evaluation strategies?

Question: As far as I am aware, most functional programming languages today use a call-by-value eager evaluation strategy with some exceptions like Haskell. I am curious if it is possible for a language to have a mixed evaluation strategy: for example, a language where everything is evaluated lazily by default but some functions can be marked as eager and are evaluated as such. I am not interested about emulating different evaluation semantics (like using thunks to create laziness) but where the language itself allows for mixed modes.
Comment: https://wiki.haskell.org/Performance/Strictness#Evaluating_expressions_strictly - when you want eager behavior in Haskell, you can have it
Comment: Thanks a lot @Dmitry! It seems like the `!`, `seq` and `deepseq` does what I am thinking of. However, it looks like`seq` introduces a dependency between two expressions so you're forced to evaluate one. To me, this is similar to how in OCaml (an eager language) you can create laziness by taking advantage of the fact that the body of a function is not evaluated when the function is defined, but only when it is applied. My question is if its possible for a language to be defined so that it can switch completely between eager and lazy evaluation based on certain contexts.
Comment: For example, consider the following hypothetical language where `leteg` can be a reserved keyword that forces the language to evaluate its expression. `let a = 10 + 10; leteg b = 20 + 30; print a`. Here, we should expect that right before the program executes the print statement the reduction graph contains a thunk for `a` and a value of 50 for `b`.
Answer: Almost every mainstream programming language mixes strict and eager evaluation. In particular, in almost all mainstream programming languages, subroutine calls, function applications, and operator applications are evaluated eagerly, except conditional operations.
For example, in C, foo ? x : y will only evaluate y if foo is false and only evaluate x if foo is true. foo is evaluated eagerly, but x  and y are evaluated lazily.
There are some programming languages which eagerly evaluate both branches, but they are very rare, and not mainstream.
Comment: Perhaps I wasn't clear in my post. For example, in C we can have

`int a = 10 + 10; int b = 20 + 20;
printf("%d\n", a);`
The program will allocate memory for `a` and put the computed result at that location. It will do the same for `b` and print it out.

In Haskell, the equivalent program will allocate some memory (thunks) for both but it will never actually compute the value of `b` because it is never used since we only print the value of `a`. I was looking for languages where you can 'force' that computation. It seems it is indeed possible with `!` operators in Haskell.


How can we restrict access to a web service to specific client computers?

Question: We have a web application (Apache/PHP) that currently uses username/password authentication and is currently accessible from anywhere. It has server-side SSL enabled.
Our client program is a version of FireFox that we have modified and rebranded. This modified firefox client is meant only to connect to our web application server. Users must use this client program to connect to the web service.
In addition to user authentication, we would like to block access at the server level to anyone who is not using our client program*. So if a user types in a URI using a regular browser, they would be denied outright.
To accomplish this, the client program needs to identify itself to the server so that the server knows the our client program is being used and not a web browser or bot.
*The real goal is to make sure that they are authorized employees of our company before being able to attempt a login, embedding this "proof of employment" into the client program just seems to be the easiest way to do this, since the application is only given to people who have a need to use it..
So far, I've had a few ideas on how to accomplish this.
1.) Embed a tolken into the client application that gets sent when the client does a login (login is handled by a chrome/XUL interface). This wouldn't block at the server level, just at the application level. The key could be stolen as easily as a password, but not guessed by brute force as easily since it could be any length or complexity.
1a.) Add a special tolken parameter to the client browser header on all requests. This is more like security-through-obscurity, but could certainly slow down an attacker trying to brute force passwords if login always fails (even with the right password) when the magic string is missing from the request..
2.) Embed a client SSL certificate into the client program. This seems like it might be a good solution, but good documentation on cleint-side SSL is almost non-existent. We would NOT want to sign a certificate for each user, nor would we want the user to have to create a certificate or be bothered with security dialogues at all. The private key would have to be imbedded into the browser, and would be one key shared among all client programs, and distributed per-installed in our custom browser.
3.) Check the user agent string. I think Apache can restrict based on this. But it seems like a weak measure at best. I would probably do this in addition to other measures.
I'm hoping for a better idea on how to do this?
Comment: What on earth led you to needing to distribute your own browser for a web app???
Comment: @Grant: we do the same; this ensures that any client can work with our webinterface, even those who run ie7. it's easier to maintain a webapp if you have to test only one browser.if you have organisations as customers, not hipsters, what would you suggest?
Comment: @Nick: i'd opt-in for solution 2 too. regarding documentaion on "apache ssl client authentication": [take](http://wiki.linuxwall.info/doku.php/en:ressources:dossiers:apache:client_certificate) [that](http://linuxconfig.org/apache-web-server-ssl-authentication)
Answer: Including a client SSL certificate with the modified browser would be easiest and probably more secure.
If you are using the same key for everyone you lose many of the advantages of client certificates, but its better than checking useragent. And I assume you will still require a username and password to login.
Answer: Have you  thought about VPN? That sounds like exactly what you really want.


Historical US federal income tax rates

Question: Is there any good online source for historical federal income tax rates in US comparison? I'll explain the problem: there are may good sources for marginal rates and income brackets, what I am interested in is the source that allows to compare effective (as opposed to marginal) rates and also do that in constant (i.e. inflation-adjusted) dollars and relative to income percentiles. I.e. I'm looking to answer the questions: "How much tax would individual earning equivalent of $80000 today would pay through last 100 years?" or "How much would a person earning median/top 10%/bottom 20% income pay through last 100 years?"
I believe all the data to answer this is there, but I didn't find any application/tool that allows to easily manipulate them to answer such questions.
Comment: I suggest visiting a library and getting up close and personal with Google. Tax structures have changed dramatically in the last 100 years, so its going to be difficult to actually compare taxation historically is a meaningful way.
Comment: " I didn't find any application/tool that allows to easily manipulate them to answer such questions"  Excel or Google spreadsheets would let you do this.
Comment: You're only going to need to go back 97 years.  The modern income tax started in 1913.  Ironically it was the same year the creature from jekyll island was unleashed (i.e. the FED).
Comment: @duffbeer703 I kinda know about Google. I can find the data and spend time and write a program that does that by myself, in theory. In practice, I don't have time for that right now, so I wonder if somebody already did it.
Comment: @Michael that's like somebody asking "how can I read Microsoft Word document" and getting an answer "Use C++ compiler to write a program to parse the format and you're fine". I kind of hoped to get pointers to existing tool, if one exists. It can't be I'm the first one in the world asking such questions.
Comment: @Muro of course, I didn't mean 100 years exactly :) I used it as a substitute for "as long ago as there's data".
Answer:
"How much tax would individual earning
  equivalent of $80000 today would pay
  through last 100 years?"

Do you mean in today's dollars? If so, you don't need to worry about converting to today's dollars.  Just calculate how much tax they owe by using the chart you pointed to, or download the excel spreadsheet they provide.
If you mean in actual dollars (not real dollars), then just take your answer, and plug it into this calculator, which takes the consumer price index into effect.
If you would like to calculate this for many different years, follow this procedure.

Download the excel spreadsheet from taxfoundation.org
Add some new columns to calculate the total tax paid in different years using the data, and keyed off a "salary" cell which you can change.
If you want to convert to dollars of that year, plug the result into the CPI calculator (or add the multiplier from the CPI calculator to your spreadsheet and do fun things with it).

I realize this takes a bit of familiarity with spreadsheets and formulas, so I started it for you back to the year 2006 here.
Comment: Note that this only took me 3 or four minutes.  You could do all of the years in probably another half hour. If I get really bored, I'll just end up doing it :P
Comment: thanks for doing it :) I hoped it was already existing as application, but looks like it isn't, so maybe I'll invest some time into making some spreadsheet like this

Historical US federal income tax rates


Best practice for running SQL Server reporting services. Should I run on the database or web server?

Question: I am configuring a new environment to run several intranet web applications.  I have 2 servers, one will be the SQL Server 2008 server, and the other will be the IIS server.  I also need to install SQL Server Reporting Services.  I am not sure whether it would be better to run reporting services on the database server, or web server.  Is there a best practice for this situation?
Answer: Depends...
The reporting services rendering is fairly processor intensive so you need to keep that in mind.  Typically if I'm designing a system with heavy load or throughput requirements I place the reporting services instance on its own server.  The best practice is really dependent on the complexity of your system.
If a third server is not an option and the two servers you already have are similarly speced I would probably place it on the one with the lowest processor load. If you place the reporting server on the web server make sure that Reporting services uses your dedicated database server for the reporting services meta-data so that you don't have to install the RDBMS on both machines.
You need to keep in mind that if you don't place the reporting server on the same box as SQL server you will need another SQL Server license. The product is only "free" if it is installed on the same machine as SQL.
Answer: I would run installer on your web server so that the web service components of Reporting Services are installed there.
It is also benificial to configure reporting services with it's own application domain in IIS so that you can tweak the configurations independant of say your other web applications.
When you run through setup using the Reporting Services Configuration Tool, set up the database on your non web server (i.e. dedicated db server). This way all your data processing is handled on one server and all your web processing/data rendering is handled on another.
Hope this is clear and of use but please feel free to pose further questions.
Cheers,John
Comment: It's not the same as installing say two instanes of SQL Server on two different servers (assumung a per processor license model). A single functional Reporting Services Platform is made up of 1 Instance of SQL Server + 1 Report Server Web Service, irrespective of where the components reside.
Comment: 2 boxes would require 2 licenses, not 1


Things in 2D world, i.e. a world with 2 spatial dimensions

Question: There are many question about life and physics in higher dimensions.
but is there any physical thing (i mean things like force, momentum, speed,...) that cannot exist in 2D world?
could 2D world have life forms(not necessarily the life form we have) or  there is something used by life that needs at least 3 spatial dimensions?
Comment: While not by itself a physics book I would recommend reading "The Planiverse" which is a fairly well researched attempt at describing physics in a 2D world.
Comment: Possible duplicate: https://physics.stackexchange.com/q/77883/2451
Answer: Let us start with Newtonian mechanics. For any point particle, position, speed, acceleration, momentum and force would still make sense, with two components instead of three. But the question is then how those forces would be modified.
Let us look at gravity for example. If we were to assume the same form for the equation the gravitational field $g$ is solution of,
$$\DeclareMathOperator{\div}{div} \iint_S g.dS = -4\pi M$$
where $S$ is a closed surface and $M$ is the mass inside $S$, then instead of getting a force in $1/r^2$, we would get a force in $1/r$, or equivalently a gravitational potential in $\log r$, in the classic two-body problem. This leads to very different a phenomenology, as such a force field does not result in close trajectories (Bertrand's theorem). So the Earth, for example, would keep "precessing" around the Sun, never coming back to the same point. The Ephemerides of the Solar system would be a lot of fun!
The equivalent Quantum mechanical problem of the Hydrogen atom, would also have a potential in $\log r$ if we assume the same form of Maxwell equations. This result in unbounded energy level: they go to $+\infty$ as the quantum number $n$ goes to $+\infty$, which completely changes the phenomenology of ionisation and conduction. I will find some interesting references when I get back to my desk!
Comment: WOW! nice! really looking forward to more physical things in 2D
Answer: Yes, life can exist in a 2D world. This was done by a long simulation experiment called Conway's Game of Life where signs of life were shown by tiles on a computer screen(search it up for details).
It is true that life would be vastly different and in a 2D world the laws of physics would have to adapt to allow formation of molecules etc.( e.g. In a 2D space, if laws did not modify, elliptical orbits would be impossible)
Remember this, just because a mathematical framework for this exists does not mean it is truly something physical. The models we create should fit what we observe to create a satisfactory model in physics.
Comment: @Jold Fans of Life have constructed self-reproducing structures that can evolve.
Comment: I think you're misunderstanding Conway's Game of Life. It doesn't prove life can exist in 2D, and it doesn't "show signs of life."