"Switch to mobile data" setting - Will apps configured to do updates etc while in wi-fi only mode use mobile data if wi-fi is down?

Question: I have a number of apps that have settings to require a wi-fi connection in order to synch/update/download and I have them configured as such.  What I'm wondering is if I have wi-fi on and configured to switch to mobile-data when the wi-fi connection is lost and now the only connection I have is via mobile data, from the Android/app perspective, is this still considered wi-fi mode and said apps will update using mobile data?
Answer: Depends on the app.
It is possible, for the app developer/creator, to check if you are using wi-fi, and it is also possible to enforce the app to only use this kind of connection. However, there can be apps that are not well made that doesn't make these checks. Usually, if they have this configuration, they will use only wi-fi (if that's the way you set).
The best way to check if the app you are using is reliable is reading user comments of each app - usually, if one user notices the app was supposed to use wi-fi only and it doesn't, he posts a complaining "one star" comment there.


High Voltage input and output microcontroller

Question: I am new to this, but I am looking to regulate a few ballast controlled fluorescent lamps with a micro-controller.  Everything I look at has a low operating voltage and below 10 volt input/output voltage.  I want to have a/c hookup to the microcontroller with full power output to the ballast (when told to do so by the program on the chip).  Am I misinterpreting what the input/output and operating voltages mean, or are high voltage applications of microcontrollers not too common? I was looking at some arduino products or something similar.  Any direction or clarification is much appreciated.
Comment: There's some "HV" microcontrollers, i.e. Atmega8/16HVA: http://www.microchip.com/wwwproducts/en/ATMEGA8HVA
Answer: I think all microcontrollers operate on 5 volts or less, and all inputs/outputs are also 5 volts or less.  It is very common to have level translators between the microcontroller and whatever it is controlling.
To control 120 volt (or 230 volt) AC devices, you could use a mechanical or solid state relay that could be driven by the microcontroller..
Answer: Usually you do not switch something directly with a microcontroller. You switch something that swithes something other. In this case you will probably have to switch a transistor that will switch a relay that will switch AC to your load.
Something like this:

simulate this circuit – Schematic created using CircuitLab
You might find a low switching voltage and low current relay that could be driven directly from a microcontroller pin, but this way I've shown you can use almost any relay.
Answer: I'm not sure if there are microcontrollers which can handle more than 5 volts and PLCs are the ones used by industry for such a situations. But as was pointed out by others, whenever we need to control voltages higher than 5V we use switches as interface. basically we control a switch which has a bas voltage of 5V and it controls the higher power line, what ever bigger than 5V. MOSFETs and BJTs are two good examples of such a transistor switches. they basically have three pins. one 5V input and two xV input/outputs where x>5. By switching the 5V pin one can open or close the xV connection.


Can the fuel on the wing cause the aircraft to destabilize?

Question: If fuel is stored in the wings, which are in constant movement during the flight, can the fuel unbalance the aircraft?
Comment: There are baffles inside to minimize sloshing.
Answer: Yes it can. Source: I'm a pilot.
Most aircraft (even many small general aviation ones) have balance parameters where the fuel quantity in each side cannot/should not exceed that on the other side by greater than a certain amount.
Note that this is usually caused by fuel consumption in flight, not sloshing as you asked.
Also, (as in your question) fuel can slosh between tanks in most aircraft through the vent line that often connects one tank to another such as in light Cessnas. However this is usually only a small quantity and furthermore the aircraft is usually in level flight so it's not really a problem.
Fuel sloshing inside of one tank could potentially imbalance the plane a bit but I've never ran into any real effects of this nor heard anyone mention it. Furthermore, most aircraft have some sort I baffles in the tanks (usually wig ribs) that prevent much sloshing, whether by design or not.
Comment: For example, Airbus A320, for fuel umbalance, 300 kg.


Dart enters one area, but tip enters another

Question:
In the picture, the dart enters through the single 19 area, but the tip goes under the metal separator and sticks in the double 19. What is the correct way to score this?
Answer: The current rules of darts, as established by the Darts Regulation Authority, can be found here. The PDC refers to them on their Rules of Darts page. The rules state the following:

5.4.2 A scoring dart is counted by reference to the segment into which the point of the dart enters and remains in or touching the face of the dartboard.

Now, what is a segment? There's no explicit definition, but the following rule suggest they'd never expect a situation like in the question to happen:

5.5.7 All the wires forming the doubles and trebles segments, inner and outer centre rings which together form the "Spider", shall be affixed to the face of the dartboard in such a manner that they lie flat on the face of the dartboard and feature no gaps or splits.

I'd argue that the dart is in the double 19 segment (its tip is fully in the green zone) so it counts as a double.

Now what would happen if it's exactly on the white/green border? There's always a catch-all rule:

5.4.8 The Referee shall act as an umpire in all matters pertaining to these General Playing Rules when conducting a Darts Event and shall, if it is necessary, consult with Scorers and other Officials before announcing any decisions during the course of Match play.

Or perhaps more explicitly:

5.3.9 The Referee will have the final say in all matters relating to starting and finishing.

though this may happen during the 'scoring' phase of a game as well.
Comment: I don't know anything about darts, but based on 5.5.7, if this situation is never supposed to happen, then maybe the board itself should be considered defective, and the rules about broken or bad boards should apply. IMHO the fairer solution from the point of view of all contestants is to replace the board and redo the shot.
Comment: Good quotes, but I believe the wrong conclusion. That dart, as per OP's wording "enters through the single 19 area", and is therefore a single 19.
Answer: You score based on the wire-defined segment, not where the tip is.   In the photo, that dart scores single 19.
The wires are there specifically to avoid any ambiguity about the location where the point touches.
From 2024 DRA Rules, the first two scoring rules refer only to scoring based on the wires and rings, not any other criteria (such as location of the tip).

6.4.1 A dart shall only score if the point of the dart remains in or touches the face of
the dartboard within the outer double wire and, having been "called", is
retrieved from the face of the dartboard by the Player throwing that dart.

6.4.2 A scoring dart is counted by reference to the segment into which the point of
the dart enters and remains in or touching the face of the dartboard.

The tip of the dart must remain in contact with the board to score (it can't be "hanging" on the wire with the tip clear of the board).  But the location of the tip on the board is not relevant.  Only the segment that is entered determines the scoring.


Javac: changing *.java does not change *.class

Question: I am compiling and running some java code on a remote machine via ssh. I code on my laptop, commit to an svn repository, then update the remote working copy and re-compile the updated source files (both machines are running Linux). I've noticed that if I change a print statement in my code the output on the remote will not change. The source, however, is updated correctly. I suspect the problem is with my build script, which is pasted below:
<code>cd $HOME/WindowsProfile/Desktop/torcs/versioned/anjiTest
export MYCLASSPATH=$HOME/WindowsProfile/Desktop/torcs/versioned/anjiTest/properties
for i in `ls $HOME/WindowsProfile/Desktop/torcs/versioned/anjiTest/lib/*.jar`
do
export MYCLASSPATH=${MYCLASSPATH}:${i}
done
MYCLASSPATH=${MYCLASSPATH}:$HOME/WindowsProfile/Desktop/torcs/versioned/anjiTest/build/classes
MYCLASSPATH=${MYCLASSPATH}:$HOME/WindowsProfile/Desktop/torcs/versioned/anjiTest/properties

echo $MYCLASSPATH

pwd
rm -R build/classes/*

javac -sourcepath ./src/ -classpath $MYCLASSPATH  ./src/A/*.java -d ./build/classes
javac -sourcepath ./src/ -classpath $MYCLASSPATH  ./src/B/*.java -d ./build/classes
javac -sourcepath ./src/ -classpath $MYCLASSPATH  ./src/C/*.java -d ./build/classes
</code>
My application relies on a large number of external libraries, which come as jar files- these are included in the classpath. I have physical access to the remote machine and I also noticed that if I build on it using NetBeans 6.9 the same problem occurs from time to time.
Thanks.
Answer: Resolved. The script above is fine.


how to increase Apache mod_proxy Jetty 5minute timeout

Question: we use Apache and Jetty to do install components behind a firewall. Some actions take a while ( 10-15 minutes ). Apache is the proxy and Jetty is the proxy target on some machines. Everything works fine for actions taking less than 5 minutes. Actions taking longer than 5 minutes fail with a 502 proxy error.
I have seen some similar topics and the advice was to define timeout and keepalive - both did not help.
our setup ist:
Windows 2012R2
Apache 2.4.9
Jetty 7
Initially I forgot to mention that there is a firewall between the apache and the Jetty.
In apache httpd.conf we have:
ProxyPassMatch       ^/([a-z0-9\-]+)/(.+)$ http://$1:3000/$2       timeout=3000 ttl=3000 Keepalive=On

We hoped that timeout=3000 ( 3000 seconds ) would keep Apache waiting for about 50 minutes for the response from Jetty. Keepalive and and ttl are trials ...
On Jetty we are calling a simple Groovy script that simply sits and waits for a long time. If the waittime is small this works as expected. If the waittime is beyond 5minutes we get an error:
Apache Access: ( the request starts at 17:25 )
xxx.xxx.xxx.xxx- - [02/Apr/2016:17:25:47 +0200] "GET /server/scripts/waitlong.groovy HTTP/1.1" 502 445 "-" 300509428 "-" "10.119.1.20" 10.119.1.20 3000

As you can see the duration is about 5Minutes ~ 300509428 and thus a timeout - it should have lastet for 10 minutes.
Apache Error: ( the request times out at 17:30 )
[Sat Apr 02 17:30:47.815050 2016] [proxy_http:error] [pid 11656:tid 12736] (OS 10060)A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.  : [client 10.119.1.20:60466] AH01102: error reading status line from remote server w-bidb1hf:3000
[Sat Apr 02 17:30:47.815050 2016] [proxy:error] [pid 11656:tid 12736] [client 10.119.1.20:60466] AH00898: Error reading from remote server returned by /w-bidb1hf/scripts/waitlong.groovy

Any ideas how to do to keep Apache waiting for a longer time ??
Answer: You might try using quotes around the regex and url, as indicated in the Apache documentation, while leaving the key value pairs without quotes.

Example
ProxyPass "/example" "http://backend.example.com" max=20 ttl=120 retry=300

It may be that without the quotes, the server is not reading the ProxyPassMatch as you intend and does not recognize where the basic parameters end and the key values begin.
Comment: tried it - did not make a difference: still timeout after 5min


Which Factor GUI tutorial/example app?

Question: Is there a non-trivial example application written in Factor language, pregerrably for GUI application which could server as a language tutorial?
Answer: A little late, but theres Factor bindings for Qt in the works. They should be in a usable state reasonably soon.
Comment: How soon? Can't find anything in Factor 0.94.
Comment: Sorry, I haven't kept up to date with Factor. I was very very briefly involved in an effort to get Qt working, but then I jumped ship in favour of clojure, so don't know if the Qt support ever matured or if there are still people working on it or not.
Answer: Don't know whether that qualifies for a "non-trivial", but there is a calculator example: http://re-factor.blogspot.com/2010/08/calculator-with-gui.html
(github: https://github.com/mrjbq7/re-factor/blob/master/calc-ui/calc-ui.factor)

Which Factor GUI tutorial/example app?


Should Reset Page be underlined if not what constitutes WCAG rules?

Question: I have a reset page text where it returns back to it's last saved state. Should this be underlined? Below you can see an open/close section which I do not have underlined. I know links that navigate somewhere should be underlined or a different color from body text. Considering WCAG does that mean everything needs to be underlined? I haven't found clear info. I feel that it does not need to be underlined but I have seen numerous sites clearing changes underlined also.
Answer: "Reset page" is an action, and as such really should be a button. And as a button, the rules for buttons would apply here, which say:

The types of actions performed by buttons are distinctly different from the function of a link (see link pattern). It is important that both the appearance and role of a widget match the function it provides. Nevertheless, elements occasionally have the visual style of a link but perform the action of a button. In such cases, giving the element role button helps assistive technology users understand the function of the element. However, a better solution is to adjust the visual design so it matches the function and ARIA role.

(emphasis added)
Or in other words: Just make the button look like a button.
Comment: Thanks for the reply. I tried the button option put prefer it without the border would using a ghosted button (no border) satisfy the assistive technology which would see it as a button just without the border.


How does Civimail reply tracking and forwarding work?

Question: Track replies and forward replies are ticked for a particular mailing. When someone replies, exactly how does CiviCRM determine the address to forward the mail to. The reply is using VERP. Is this clearly documented somewhere? I have looked at the documentatin on civicrm.org (book, wiki) and cannot find any details.
Answer: CiviCRM uses Variable Envelope Return Path (VERP for short) to track bounces and optionally replies.
This technique assigns a unique, coded address to two aspects of a CiviMail email. Viewing the mail headers, you might see something like
Return-Path:      <email@example.com>
X-Civimail-Bounce: email@example.com
Reply-to:          email@example.com

Here's a breakdown of what you're seeing -
civimail         - the mailbox name of email@example.com
+                - VERP separator
b                - action - (b|bounce|c|confirm|o|optout|r|reply|s|subscribe) etc
1234             - mailing job id
1234567          - mailing queue id
aabbccddeeff1122 - validation hash

SMTP systems understand these headers, so if the message is undeliverable they should return the bounce to the Return-Path address, and if the person hits reply their mail client should use the Reply-To address. This depends on correct behaviour in the MTA and MUA, both of which are outside of control of CiviCRM.
The main place this is used is in the email processor at CRM/Utils/Mail/EmailProcessor.php, where CiviCRM checks for these strings either in the message headers this bounce/reply was delivered to, or in the body of the message (some mail systems don't permit VERP delivery; expect less ideal results without full VERP support).
... That's how it works under the hood! Joe's answer explains this well from the other side of the dashboard :)
Answer: At Administer > CiviMail > Mail Accounts you can configure one or two email inboxes to be automatically processed by CiviCRM. The Bounce Processing inbox handles the processing of replies to emails along with soft and hard bounces, unsubscribe emails and opt out emails.
The VERP information on the return message  is used to correlate the incoming email to CiviCRM with the outgoing one from CiviMail.
When Track Replies is enabled for a mailing, and a.reply is received, a copy of the reply is stored as an Activity for the person who had been sent the CiviMail.
If Forward Replies is enabled and CiviCRM receives a reply, it sends a copy of the email to the From address used in the Mailing. The possible From addresses for CiviMail can be configured at Administer > CiviMail > From Addresses.
If you don't want to track replies using VERP, navigate to Administer > CiviMail > Component Settings and disable 'Track replies using VERP in Reply-To header'.
Comment: Is the value of the VERP address stored in the database? Also, is it possible to do this without VERP by using a catchall mailbox. Our SMTP provider does not seem to be able to set up VERP
Comment: Could you add the question about not using VERP as new, separate questions in Covicrm.stackexchange.com?
Answer: Joe wrote above :

When Track Replies is enabled for a mailing, and a.reply is received, a copy of the reply is stored as an Activity for the person who had been sent the CiviMail.

I performed a lot of tests, and I came to the conclusion that this is not so simple.
I haven't been able to store easily as an activity the replies sent to the Reply-to address (firstname.lastname@example.com in the above example)
After running the "fetch bounces" scheduled task, Civimail report correctly displays that a response has been received, and that answer is moved under the IMAP subfolder "civimail/processed" of the bounce email account.
BUT NO copy of that email is attached as an activity to the civimail recipient (who sent an answer to the mass mailing).
I had to use the following trick :

in the imap mailbox, create a rule to copy all emails sent to "civimail+r." to a subfolder called "civicrm-answers". All those emails are now duplicated : they appear both in "civimail/processed" (bounce processing) and in "civicrm-answers"
in civicrm, create an additional "email to activity" account, monitoring "civicrm-answers" IMAP folder
after the execution of the task "Process Inbound emails", the reply is now correctly stored as an Activity for the person who had been sent the CiviMail

This is quite complex, and it would be so simpler if the "fetch bounce" task could at the same time store the reply as an activity (and not only increment the amount of replies in the civimail report).
Am I doing something wrong ?
Comment: It sounds like you are asking a question here, but you have posted this as an answer. You are more likely to get a response if you post a new question. If relevant refer to this one.


Rib Roast Rare standing up or lying down?

Question: I have a 4 inch thick one which I'd like rare. Will it make a difference if I cook it standing up or flat in the pan? And at what temperature? I have an electric oven.
Answer: Use the ribs as a roasting rack. In the spirit of the day, I will share with you my favorite technique. For rare, rare, cook to 120F (49C), that will carry over to 125F (52C).


Ubuntu 18.04 LTS won't boot after installing video drivers

Question: I recently converted my Windows 10 laptop to a full Ubuntu machine. Everything was working fine until I was installing some video drivers and when I went to restart the computer it wouldn't boot properly. The Ubuntu logo shows up but then the screen starts to flash black. After that, it's just a black screen with a flashing white underscore. While the Ubuntu logo shows if I press the up arrow the last thing that shows up is "Started User Manager for UID 1000." When I press the power button the Ubuntu logo shows up again. I'm running Ubuntu 18.04 LTS. Thank you for your help in advance.
Answer: To install a graphics card that matches your computer's configuration, go to "Software & Update", select the "Additional Drivers" tab, select the driver listed in it, Apply Change, after finishing, reboot. computer


trying to read rtf file from Jar to JEditorPane; works in Netbeans, not from Jar

Question: sorry if this is obvious, but I've been looking for days and I can't seem to find the answer.
Here is the situation.  I am trying to read from an rtf file located within a jar file and then display it in a JEditorPane.  This is working from the Netbeans environment, but not when executing the jar file in the dist folder.  A version of this question has been asked before, but for my application I think I don't think the previous answers apply.  (The reason is that JEditorPane.read requires a FileInputStream, and all of the solutions to other problems I have seen have involved non-File InputStreams.  Here is the code in question:
descPane = new JEditorPane("application/rtf", "");
   try {
       File test = new File(this.getClass().getResource("files/general.rtf").toURI());
       descPane.read(new FileInputStream(test), null);
    } catch (Exception ex) {
        Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
    }

Any help is very appreciated!  Thank you!
Answer: Use the URL obtained from getResource() to load the document.  If it is in a Jar, it will not be accessible as a File.
Something like this:
URL urlToRtf = this.getClass().getResource("files/general.rtf");
descPane.setPage(urlToRtf);


He still thinks that what he sees in the TV and movies is real

Question: Is the verb agreement correct in this sentence (...
is real and not ...are real)?
Answer: I think in this case "what he sees" is a group noun.

A noun that denotes a collection of persons or things regarded as a unit.

"A unit" means singular, therefore "is" is in agreement and "are" would not be.
The phrase "in the TV and movies" does denote plurality, but it is just an adjective phrase modifying the singular noun group "what he sees". Subject and verb agreement is between the noun (group) and the verb, not the modifying adjectives.
I am not a very skilled grammarian, so I think my terminology is off, but I think I have the crux of it right.
Comment: I think you've got it.  I just want to also point out that instead of *in the TV and movies* I would normally expect to hear (or say) *on TV and in the movies*.
Comment: Yes - 'what he sees' etc will take singular or plural agreement depending on context. Often it's obvious: 'What I see here are different meanings' // 'What I see here is pure unadultarated beauracratic harrassment'. 'What I watch on TV are films and documentaries' is fine, but 'What I watch on TV – films and documentaries – is worth the licence fee' treats the whole of 'what I watch' as unitary. As you say.


trouble referencing Windows Portable Device files in VBA?

Question: I have been tirelessly searching for a solution to my problem but have not found anything helpful!! So I hope someone on here can help my specific situation... Thanks in advance!
So, I have a barcode scanner that stores inventory in its internal memory as a text file. Through the use of Windows Mobile Device Center 6.1 I am able to, on my PC, navigate through the scanners folders and open up that text file to see what items I scanned.
I am writing an excel macro that will open up that text file, read each line of inventory, and then do other things with it. I have been successful thus far if I copy that text file on the scanner into some places like 'My Documents'. However, I want to make it easy and be able to open up that text file directly from the scanner.
My problem is with referencing the path to the scanner. Because it is a portable device, it does not have a drive like C: or something. Instead the path looks like 'Computer\MT2070-ML416147\Application\Inventory\export.txt'. However when I try to open that path for input I get an error saying "Path not found".
If anyone can assist I would be very appreciative!! If anyone requires code snippets of what I have, please let me know.
Answer: There is no way to access the contents of attached Windows CE device's filesystem through the Windows filesystem API, this is because they are not mounted volumes. Your device appears in Windows Explorer because WMDC installs a Shell Namespace handler that creates shell folders that represent the attached device - this is the same way that the Control Panel and Network Places folders work, even though they too are not true filesystem directories. Think of it as Windows hand-waving over the filesystem abstraction.
All is not lost, however, you have a few options:

Use the Smart Device Connectivity API to explore the device and get data files out of it: https://msdn.microsoft.com/en-us/library/bb384093.aspx - this is the same API that Explorer is using when it shows you shell folders of the device.
Remove the storage volume (e.g. an SD card) from the device and plug it in to an SD card reader on your computer so you can browse and manipulate  the filesystem directly.
Write a program that runs on the device itself to push data from the device to a shared location.

Option 1 will get you the best results but will likely require coding against it in C++/Win32. VBA is not the best environment to do systems programming in. You can always write in C++ and expose your layer as a COM object which you can then consume through VBA. Though you'll run into problems with 32/64-bitness of Office, and probably sandboxing issues too.
Option 3 will be slightly difficult as the last SDK for the "Windows Mobile" flavour of Windows CE was released for Visual Studio 2008 - there is no support for more recent versions of VS. That means using either the anemic Compact Framework 3.5 or C++03 against the WinCE API. Coincidentally, I believe this is part of the reason Windows Mobile was doomed when the iPhone came out: the environment was just too neglected and behind it couldn't keep up.
Comment: I thought you had a GREAT Answer; especially option 1.  Just wanted to comment, though, that I think VBA IS a great environment for doing systems programming.  Having been an assembly, C, C++ programmer all my life (50+ years) I've found VBA much more practical for all my systems programming that doesn't require speed.  So far, i haven't found anything I can do in Assembly or C/C++ that I can't do in VBA.
Answer: Check if your device is accessible via Shell.Application ActiveX. Below is the example that shows all items in "Printers and Faxes" location:
Sub Test()

    Set objShellApp = CreateObject("Shell.Application")
    Set objFolder = objShellApp.Namespace("::{2227a280-3aea-1069-a2de-08002b30309d}") ' Printers and Faxes

    Debug.Print "CLSID:" & vbCrLf & objFolder.Self.Path & vbCrLf
    Debug.Print "Folder name: " & vbCrLf & objFolder.Self.Name & vbCrLf
    For Each objItem In objFolder.Items()
        Debug.Print objItem.Name
    Next

End Sub

The output for me is as follows:

CLSID:
  ::{2227A280-3AEA-1069-A2DE-08002B30309D}

  Folder name:
  Printers

  Fax
  Microsoft XPS Document Writer
  PDFCreator
  Send To OneNote 2013
  ...-P0086 on ...-s0002
  ...-P0087 on ...-s0002
  ...-P0049 on ...-S0002
  ...-P0068 on ...-S0002
  ...-P0067 on ...-S0002

Try another CLSIDs, like:
::{20D04FE0-3AEA-1069-A2D8-08002B30309D} - Computer
::{00f2886f-cd64-4fc9-8ec5-30ef6cdbe8c3} - Scanners and Cameras
::{fb0c9c8a-6c50-11d1-9f1d-0000f8757fcd} - Scanners and Cameras
::{e211b736-43fd-11d1-9efb-0000f8757fcd} - Scanners and Cameras
::{0c15d503-d017-47ce-9016-7b3f978721cc} - Portable Device Values
::{35786d3c-b075-49b9-88dd-029876e11c01} - Portable Devices

Take a look eg here, here and here. If you find the device name in one of the displayed items, then you will apparently be able to retrieve the file from it.
Comment: You can't believe how much your sample code helped me!!  Thank you!!  Can't believe it's over 6 years old and it's still helpful


Training data from real hardware

Question: I am working on machine learning model. The target is to learn the behavior of a black box which has a couple of inputs and one output signal. I have generated some training data by applying different input signals to black box however I am facing an issue, i.e., for a given set of input values the black box does not generate output signal of fixed value. Instead, the value of output signal varies a little. It is like adding a little variability to the output signal. My question is how shall I use my generated training data to model the black box behavior? Ideally, I would like to develop a NN model that for a given set of input signal values estimates the mean value of output signal as well as the min/max range.
Answer: I would start with some exploratory data analysis techniques before jumping into models. Visualizations of the data can save a lot of time.
I'll assume that features are fixed. Otherwise you might consider feature selection techniques.
Once you have explored the data, then you might start considering choices of model. You sort of answered your own question that you could train a neural network on the data generated from the black box. Just make sure you split the data into training, validation, and testing sets as usual for such ML projects.
But I would recommend starting with simpler models than typical neural networks. The failures of simpler models can hint at what improvements should be used, and you might luck out at a simpler model doing the trick.

Training data from real hardware


Put .jpg photos in app's App folder to use DBRoulette

Question: I downloaded sample project from www.dropbox.com/developer.In that sample drop box is connected but random photos doesn't loaded to drop box.It display alert message such as "Put .jpg photos in your app's App folder to use DBRoulette".In which folder i put photos.Kindly tell about me.
Answer: That means you need to keep some photos in your Dropbox account under pothos folder which sample project is trying to fetch.
Try this and see if that works.
Answer: /Users/XXX/Dropbox/Apps/YorAppName/kick.jpg - exactly right path for "samplecode".


Magnetic shielding

Question: http://www.kjmagnetics.com/blog.asp?p=shielding-materials
I understand from the diagrams that the magnetic field is redirected through the shield (and not canceled out.. etc) Suppose I cover one magnetic pole of a bar magnet with a magnetic shield. Would there be less attractiveness in the immediate area beyond the shield in contrast to a corresponding area around the other pole?
Can I achieve something similar to the concept the image portrays of shielding part of a magnetic pole?The field lines are to be simply taken as a perceptible difference in attractiveness between each sides of the magnetic poles
Answer:
Suppose I cover one magnetic pole of a bar magnet with a magnetic shield. Would there be less attractiveness in the immediate area beyond the shield in contrast to a corresponding area around the other pole? Can I achieve something similar to the concept the image portrays of shielding part of a magnetic pole?

Aka

Within reason yes, BUT the laws of Physics and Murphy will (simultaneously) follow you doggedly no matter how hard you try to shake them off.
Halbach array: A Halbach array is an arrangement of magnets that provides an assymetric field by arranging poiles so that the fuelds cancel on onbe face.It can be made in circular and planar arrangements and has special applications in motor magnetic bearings (aka levitation) and high energy density motors.
Wikipedia - Halbach array

Launch Point HA motor makers
[NASA report - Halbach Magnetic Rotor Development - 2008](
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080013147.pdf)

If this is an attempt to make something approaching

a Monopole [tm]  (A Halbach array comes closer than most things)
a static magnetic field levitator *
a free energy device
a perpetuum mobile
an over-unity device
anything which equates static magnetic field alone with energy flow
or similar "fellow travellers"

then you may have as much fun as the many people on the web who attempt to create such devices, and about the same amount of success. (About zero is effectively equal to zero).

FWIW - long ago, knowing that it had been proven that you cannot statically levitate an object using permanent magnets, I tried to do so regardless, using constructional methods that might be expected to work were it not impossible :-) - ie dished monopole "bowl" with other poles underneath and a monopole-outside ball. As entirely expected, I did not succeed, but I learned a lot about the lengths magnetic devices amd Murphy will go to to protect their theoretical integrity :-)

Related and possibly relevant:

You can achieve levitation with a stationary magnetic field if your target is a suitably shaped rotating magnet. cf the Levitron levitating 'top'.

You CAN achieve static levitation if you include a diamagnetic material in the "magnetic circuit".
UCLA - diamagnetic levitation
... and many more
Wikipedia - magnetic levitation
Wikipedia - diamagnetism
Comment: And superconductors are strongly diamagnetic, but unfortunately all the ones discovered to date only work at very low temperatures.
Comment: @SpehroPefhany there exist many High Temperature Superconductors at higher than 120 K which is substantially above Liquid Nitrogen temperatures ( 77 K) which is generally recognized as the boundary at which it is feasible.  It certainly isn't room temp, but it's for the most part very practical and obtainable.  "Very low temperatures" is, in this field very misleading.
Comment: @placeholder Yes they exist. But there are two different kinds of Superconductors. The Meissner effect in Type 2 superconductors isn't as complete as in the Type 1 superconductors(all high temperature SC are type 2). A nice side effect is that you can "freeze" them in the flux(kind of) to create a floating magnet, which is really nice :-D.

Magnetic shielding


What is the purpose of adding new file to the database?

Question: I'm fairly new at Microsoft SQL. I've seen many tutorials online on how to add a file to the database. What I still don't get is why?
Answer: You could

put huge archive data onto a big but slow drive
put structural information ("meta data") into its own file
put indexes etc. on a fast drive
put large readonly data (e.g. old legacy data) onto a SSD
set up a more intelligent backup strategy

I'm sure there's still more to add :-)
Comment: It can also be useful for huge database transfers : if you have one big file to transfer/restore in a maintenance window... It may once be too big to fit into this window.
If you have multiple files, you can use the principle of divide and conquer.
Answer: There's several reasons one could and should do this.  One of the less discussed items is logical file contention within the MDF/NDF file.  When you have a lot of processes trying to access data in that single file it becomes a logical point of contention which will add lots of PAGE_LATCH wait times (not page_latch_io which is physical contention).  See here for more info.
As your database grows you might want to spread the files to different drives for expandability.  Of course, SQL Server uses a round robin proportional fill algorithem so you'd have to be mindful that it will create a hot-spot until it's the same size as the others.  You can read more info on that in BoL here.
Other old school reasons used to be to separate indexes so you improve writes.  This has largely gone to the wayside due to flash storage and intelligent SANs but if you need to squeeze every last bit of write IOPS out of it, then this would help.  Basically optimization.
Sometime's it's helpful to move data from old disks to new disks or if the old disks are showing bad sectors or such.
Those are some of the main reasons someone would add different files.  The main reason I do it is to avoid logical file contention however in many environments I've worked in now that SSDs and cheap RAM are so readily available, personall.


Why cross product gives area of parallelogram formed by two vectors

Question: Recently we were introduced to the concept of vectors in our class, and we learnt about dot products and cross products.I do know that $a\times b$ yields the area of the parallelogram formed by the two vectors.
What I struggle to understand is why taking the determinant leads to area of the parallelogram, i.e. how does the following:
$$
\begin{vmatrix}
 i  &  j & k \\
 a_{x}&a_{y}&a_{z}  \\
 b_{x}&b_{y}  &b_{z}  \\
\end{vmatrix}
$$
yields a vector which is perpendicular to both $a$ and $b$, and also has a magnitude$=ab sin(\theta)$? How are they connected ?
Comment: The notation you use for that magnitude reminds one of Absinthe which is a French liquor and was according to [this answer](https://math.stackexchange.com/a/4183216/949989) the main driver behind the invention of differential forms.
Comment: This should take you pretty far: \begin{align}
\|a\|^2\|b\|^2&=\|a\|^2\|b\|^2\cos^2\theta+\|a\|^2\|b\|^2\sin^2\theta\\
&=(a\cdot b)^2+\|a\times b\|^2
\end{align} For a geometric proof see this [answer](https://math.stackexchange.com/questions/4036985/cross-product-and-determinants?rq=1).
Comment: How did your teacher define the cross-product $a\times b$?
Comment: @DavidQuinn He simply told us that cross product of two vectors is defined as the area of the parallelogram formed by the two vectors, following which he told us the determinant method to calculate the cross product but without any explanation of how it is derived or proof. Our textbook too skips over this part, I also couldn't find any such proof or derivation on the internet.
Comment: The usual definition is $\underline{a}\times\underline{b}=|\underline{a}||\underline{b}|\sin\theta \underline{\hat{n}}$, where $\theta$ is the angle between the vectors, and $\underline{\hat{n}}$ is the unit vector perpendicular to both vectors following the right-hand rule.
Answer: After reading through others' responses and spending some more time on the problem I have come up with an explanation of my own for this question which I posted and am leaving it as answer over here for public knowledge and introspection.

The determinant method of finding the cross product is basically an abuse of the notation, as explained in this answer, also cited earlier in one of the replies. Ideally a determinant like this should give the volume of the parallelpiped formed by the vector $a,b$ and the vector $\hat{i}+\hat{j}+\hat{k}.$
Now,generally when we calculate the determinant given in the question, which is:
$$
\begin{vmatrix}
 i  &  j & k \\
 a_{x}&a_{y}&a_{z}  \\
 b_{x}&b_{y}  &b_{z}  \\
\end{vmatrix}
$$
we derive a new vector $c$:
$$
c=(a_{y}b_{z}-a_{z}b_{y})\hat{i}+(a_{z}b_{x}-a_{x}b_{z})\hat{j}+(a_{x}b_{y}-a_{y}b_{x})\hat{k}
$$
Upon inspecting the components of the newly found vector one can see that the coefficients of the unit vectors $\hat{i},\hat{j},\hat{k}$ are nothing but the area of projections of the parallelogram formed by the vectors $a$ and $b$ upon the $y-z, z-x, x-y$ planes, respectively.

When we calculate the magnitude of this vector, we perform the following calculation:
$$
|c|=\sqrt{{(a_{y}b_{z}-a_{z}b_{y})}^{2}+{(a_{z}b_{x}-a_{x}b_{z})}^{2}+{(a_{x}b_{y}-a_{y}b_{x})}^{2}}
$$
Let the areas of these projections be A,B,C respectively.What now needs to be proven is:
$$
|c|^2=A^2+B^2+C^2
$$
But I will be showing this for a general case instead, that is for any closed curve in 3D-space which lies on a single plane and has area $T$;
$$
T^2=(T_{xy})^2+(T_{yz})^2+(T_{zx})^2
$$
Where $(T_{xy}),(T_{yz}),(T_{zx})$ are its projection upon respective coordinate planes.
First, lets consider two planes $P_{1},P_{2}$ inclined at some angle $\theta$ with each other. Consider an area element $S$ on $P_{1}$, then its projection upon the other plane will have an area of $S(cos(\theta))$. This can be understood by same approach we apply for calculating area under curves during integration. We use infinitesimally thin strips parallel to each other under the curve. If we take similar strips in plane $P_{1}$ which are perpendicular to the line of intersection of $P_{1}, P_{2}$ then their projection on the $P_{2}$ will be of length $cos(\theta)$ times the original length. Therefore any area element($=S$) calculated for any curve in $P_{1}$ will have its projection on $P_{2}$ of area $=S(cos(\theta))$. This holds true irrespective of the orientation of the closed curve with in the plane $P_{1}$. For example for a triangle in $P_{1}$ with area $t$, its projection will have area $t(cos(\theta))$. One can rotate or flip the triangle within $P_{1}$ and can even deform it to make another shape(but with same area) but its projection's area in $P_{2}$ will remain constant as long as the area of the closed curve in $P_{1}$ and the $\angle \theta$ remains constant.
Second,now employing the De Gua's theorem for a tri-rectangular tetrahedron:
Let the right angled sides have area $e,f,g$ and the hypotenuse side have area $h$,then it follows $e^2+f^2+g^2=h^2$
Notice that  $e,f,g$ can be considered as projected areas of hypotenuse triangle with area $h$ on coordinate planes. Let them be the projections with $xy,yz,zx$ coordinate planes respectively. And from previous observations we can also conclude that :
$$
\frac{e}{h}=cos(\alpha)
$$
$$
\frac{f}{h}=cos(\beta)
$$
$$
\frac{g}{h}=cos(\gamma)
$$
where $\alpha,\beta,\gamma$ are the angles made by the hypotenuse face with the respective coordinate planes.
Remember that we have already established that no matter how we deform the original closed curve, as long as its area is constant and the containing plane retains its orientation in the 3D space( that is its angles with the coordinate planes($\alpha,\beta,\gamma$) remains same). The area of projection will also remain constant.
What that means is that we can translate the hypotenuse triangle in 3D space and deform it in anyway without opening the curve (and keeping area($h$) constant) then e,f,h shall also remain constant.
Hence, on generalizing, it follows that for any area element($T$) in 3D space and contained in single plane:
$$
T=(T_{xy})^2+(T_{yz})^2+(T_{zx})^2
$$
Where $(T_{xy})^2,(T_{yz})^2,(T_{zx})^2$ are its projection upon respective coordinate planes.
And thus we conclude that $A^2+B^2+C^2$ and $|c|$ indeed equals to the area of the parallelogram formed by vectors $a,b$.
And $\therefore$ $|c|=|a||b|(sin(\phi)$, where $\phi$ is the angle between the vectors $a,b$.
Coming to the perpendicularity of the vector $c$ to the plane containing vectors $a,b$. To understand this, imagine a unit vector $u$  perpendicular to the plane containing $a$ and $b$, let this plane be $P_{ab}$. Let the angles made by the plane $P_{ab}$ and coordinate planes $x-y,y-z,z-x$ once again be $\alpha,\beta,\gamma$ . Since $u$ is perpendicular to $P_{ab}$ the angles it makes with the coordinate planes $x-y,y-z,z-x$ will be $\frac{\pi}{2}-\alpha,\frac{\pi}{2}-\beta,\frac{\pi}{2}-\gamma$
And hence the angles it subtends with coordinate axes $X,Y,Z$ will be $\beta,\gamma,\alpha$ and hence the unit vector $u$ will have $cos(\beta), cos(\gamma),cos(\alpha)$ along them.Here, just to be clear, $\beta,\gamma,\alpha$ are angles of $u$ with axes$X,Y,Z$ and the angles of $u$ with coordinate planes $y-z,z-x,x-y$, respectively. Remember that
$$
c=(a_{y}b_{z}-a_{z}b_{y})\hat{i}+(a_{z}b_{x}-a_{x}b_{z})\hat{j}+(a_{x}b_{y}-a_{y}b_{x})\hat{k}
$$
has coefficients as area of projection of parallelogram formed by $a,b$ on $y-z,z-x,x-y$ for unit vectors $\hat{i}, \hat{j}, \hat{k}$ respectively. And we have already established that projected areas are $cos(\theta)$ times the original area, $\theta$ being the
angle between the two planes.
Therefore vector $c$ also has unit vector same as vector $u$, i.e. $cos(\beta),cos(\alpha),cos(\gamma)$. Therefore vector $c$ is perpendicular to $P_{ab}$.


What are exercise a kidney patient can do?

Question: I want to know what exercises a kidney patient can do other than jogging?
Comment: Is jogging really OK for kidney patients?

In Russia all kidney patients I've heard of were specifically forbidden from jogging by their doctors.  Having a kidney disease also exempts men from compulsory service in the Russian army.

I guess the reasoning behind it is that when you jog you slowly dehydrate your organism and leave it in dehydrated state for longer periods, which increases the concentration of urine, which then increases the probability of accumulation of minerals in bladder/kidneys («kidney stones») (but I'm not sure since I'm not a doctor).
Comment: @MischaArefiev Actually doc have suggested me to jog daily. So i m following that.
Answer: I did a quick search to see what was recommended.  While I've collected a few recommendations, I don't have the reasoning for them.  The most directly useful link was this one summarized below:

Focus on continuous activity like swimming, jogging, aerobic exercise where you move large muscle groups continuously
Light strength training is OK (lower weights higher reps)
Exercise three non-consecutive days a week
Discontinue exercise if you are dehydrated, very tired, have shortness of breath, have a fever, change in dialysis schedule.

Kidney.org had a brochure with some basic information in there:

Three main types of exercises are beneficial: stretching, strength, and aerobic
If you are completely out of shape, start with stretching and basic strength until you can sustain an aerobic exercise.
You should slow down if: the exercise feels very hard, you are out of breath when you try to talk, you feel your heart racing, or you are not fully recovered an hour after exercise.

Based on that information, heavy lifting and sprinting is not an option.  Probably some of the better options might include yoga or pilates.  Do keep a regular dialog with your doctor, as kidney issues are serious.  If they tell you to slow down, stop, or change what you are going, listen to them.
Comment: Thank you for your kind reply..i am not out of shape totally..but started to get some fat around belly.So i like to be in shape.I jog daily..have no problem with that.but still is not enough i guess as fat is still there around belly.
Comment: Then take a look at what you are eating.  Make a food journal of everything that goes in your mouth.  It doesn't have to be complicated, just record what the food was and roughly how much you ate.  It can be quite eye opening.


Which hands do not consist of sets and a pair?

Question: I know of only two hands that do not consist of 4 sets and a pair in riichi mahjong: Seven Pairs, and Thirteen Orphans. Are there more?
Answer: Based on this source I would say that those are the only ones.
Answer: In some variants you have hands like Knitting (seven cross-suit pairs), Thirteen Grades of Imperial Treasure, and the Wriggling Snake.
This page matches the rulebook I learned from. It describes several others such as Windy Chows, Dragonfly, Heavenly Twins (a special case of All Pairs), Run Pung & Pair, and Red Lantern.
I believe most of these should apply to riichi mahjong as well.
Answer: This source explicitly states that 13O and 7P are the only exceptions in Riichi.

A Winning hand is, except for two
  exceptions, composed of four MELDS
  (mentsu [面子]) and a PAIR (jantoo,
  [雀頭]). The two exceptions are the
  SEVEN PAIRS (chiitoitsu [七対子]) hands
  (covered in a later section) and the
  THIRTEEN ENDS (kokushimusoo [国士無双])
  hands (covered later in the special
  hands section)


Why did Jesus turn water into wine?

Question: It just occurred to me that Jesus lived in the middle-east, where there's not much water. Alcohol dehydrates you by making you pee more, and Jesus was supposed to be a man of the people- that is, someone focussed on helping people get from day to day. So doesn't it seem counter-productive to turn water into wine? Wouldn't it actually be more characteristic/benevolent to turn wine into water? Or was it all just to show off his superpowers and that's seen as more impressive?
Comment: Throughout much of human history, one of the chief ways of making water safe to drink has been through fermentation--making wine, beer, or other lightly fermented drinks out of it. This typically kills harmful pathogens, and results in only a slight amount of alcohol (much less than most modern beer or wine). This is likely what they had at the wedding feast. Jesus *could* have said "There's no reason for you all to be drinking wine. Let me just purify this water for you instead." and they would have looked at him like he was crazy, the miracle would not have been seen as a miracle...
Comment: Interesting point since wine was drank because it was "cleaner" than the water.  I wonder why he didn't turn it into Mountain Dew.
Comment: This could have been the only miracles of the ones Jesus performed that never happened, because it can be explained psychologically.
Comment: @Constantthin- My understanding is that the actual truth content of the Bible is off-topic. See https://christianity.meta.stackexchange.com/questions/3527/we-cant-handle-the-truth
Comment: You are right. That's why I am not saying it in an answer.
Comment: At the end of a party with too much wine, (since it ran out, they must have had large amounts of it) the somewhat intoxicated guests would very much need cold water to quench their thirst with. (alcohol is dehydrating).
Answer: Jesus was supposed to be a man of the people- that is, someone focussed on helping people get from day to day.
Why do you think so? Jesus came to redeem people by his suferring and death. Not to make their life comfortable.
Jesus lived in the middle-east, where there's not much water
Water was not scarce in Jesus's place and during his time. I don't know where you got that data from. Water was an integral part of temple ceremony and was lavishly used during sacrifice. Also Water Into Wine miracle narrative itself records there were six stone jars full of water present there just to be used in ceremonial washing. That is how much water they had. There is no contemporary record showing that water was scarce. After all, Jerusalem was supposed to be a land flowing with milk and honey.
So doesn't it seem counter-productive to turn water into wine? Wouldn't it actually be more characteristic/benevolent to turn wine into water?
No. Wine was an integral part of Jewish marriage custom at the time. Not providing sufficient wine was an insult to the guests and thereby a shame to the newly wed. Jesus helping them in their need is in fact a "characteristic/benevolent" act.
Was it all just to show off his superpowers and that's seen as more impressive?
Have you read the Gospel narrative? Vast majority of people who attended the wedding including the master of the banquet did not know where the wine came from. So your claim of show off his superpowers doesn't hold good.
Comment: "Jesus came to redeem people by his suferring and death. Not to make their life comfortable."  Way to miss the whole point of Jesus.
Comment: 1 Timothy 1:15 "This is a faithful saying and worthy of all acceptance, that Christ Jesus came into the world to save sinners, of whom I am chief."
Luke 19:10, "For the Son of man is come to seek and to save that which was lost."
Matthew 20:28, "Even as the Son of man came not to be ministered unto, but to minister, and to give his life a ransom for many."
Mark 1:38, "And he said unto them, Let us go into the next towns, that I may preach there also: for therefore came I forth."
Comment: Galatians 4:4-5, "But when the fulness of the time was come, God sent forth his Son, made of a woman, made under the law, To redeem them that were under the law, that we might receive the adoption of sons."
Answer: When Jesus turned water into wine, He performed His first miracle at the wedding feast.  It was also at the request of His mother.  He didn't want to demonstrate His power yet, but still obeyed His mother. It shows how Christians must respect Mary as Christ did.
This first miracle also foreshadowed His death on the cross as being the sacrificial lamb.  To explain, during the Last Supper, Jesus and His disciples did not eat the traditional passover meal as all Jews would have.  They did not eat a sacrificed lamb - Jesus became that perfect lamb who was broken on the cross.  What at first seems strange, they also did not drink all the different cups of wine required during the meal.  When Jesus drank the vinegar wine on the cross, He stated "It is finished."  This was the final cup of the passover meal.  When Jesus died, He completed the passover meal on the cross.
The first miracle of turning water into wine was bookended with Him becoming the passover feast.  Christians and His Church are the Bride of Christ.  The events in the New Testament correlate for very specific reasons to demonstrate His divinity and salvation.
Jesus commanded that we must eat of His flesh and drink His blood.  This was not symbolic.  Many of His disciples left because they could handle His command.  In Communion, Jesus becomes the bread and wine in Mass.  This belief was even understood by the pagans in the first centuries and was only disputed over 1000 years after Christ.  Peter commanded that you cannot have communion in a state of sin, otherwise you drink and eat condemnation upon yourself.  The miracle when Jesus multiplied the bread and fish also ties into how during Mass how Christians can still eat His flesh and drink His blood.
To be a Christian, you must believe in the actual presence of Christ in Communion.  It is a core belief, not something optional.  This is why Jesus turned the water into wine - and how he "turns Himself" into wine in Communion.
Comment: Welcome to the site!  This next has ***nothing*** to do with the quality of your answer, it's just standard to help new visitors avoid misunderstanding the site (as I did at first.)  As a new visitor, I'd recommend checking out the following two posts, which are meant to help newcomers "learn the ropes": [the help page](http://christianity.stackexchange.com/help) and [How we are different than other sites?](http://meta.christianity.stackexchange.com/questions/1808/how-we-are-different-than-other-sites)
Answer: Uta Ranke-Heinemann, among others, points out the parallels to pagan tradition in the account of Jesus turning water into wine. She says, in Putting Away Childish Things that the transformation of water into wine is a typical motif of the Dionysus legend, in which this miracle serves to highlight the god's epiphany. On his feast day, Dionysus made empty jars fill up with wine in his temple in Elis; and on the island of Andros, wine flowed instead of water from a spring or in his temple.
A similar example, also in John's Gospel, at John 5:1-9, where Jesus cured the lame man at the pool with five porches, near the sheep market outside Jerusalem.  Archaeologists have found that pool, still with a votive offering to the Greek god of healing, Asclepius. This was an Asclepium, or temple to Asclepius.  As was typical of his temples around the Greek world, whenever he came by and disturbed the water, whoever was first to enter the water would be cured. In both examples, John has portrayed Jesus as being capable of doing with great ease whatever the pagan gods could do. So these examples were to show off Jesus' powers, although it was not Jesus doing this but the author of John, and the audience for the miracle was John's readers, not people at a wedding.
At http://en.wikipedia.org/wiki/Dionysus#Parallels_with_Christianity, we find Peter Wick cited as saying, "... the use of wine symbolism in the Gospel of John, including the story of the Marriage at Cana at which Jesus turns water into wine, was intended to show Jesus as superior to Dionysus."
Comment: 1. Dionysus never turned water into wine. Jar of water turning into wine is not the same as spring giving forth wine INSTEAD OF water. 2. Just because Jesus could do somethings that pagan Gods could do doesn't mean it was purposefully made to be so. **3. This is not an answer to the question asked.**
Comment: I don't care who said that. Just because she has some degree doesn't mean we should accept what she says. See with your commonsense: Do you think `turning water into wine is the same as spring giving forth wine INSTEAD OF water.` Or you are ready to accept it just because some person with a fancy title says so. People will see what they want to see. I can show such similarities with Jesus and Nicolas Cage. It does not prove anything.
Comment: Dr Ranke-Heinemann (chair of the history of religion, University of Essen) thinks there is a parallel, to the point that she taught that one report was based on the other. If, as she says, the event did not really occur, then the answer as to why he did so is found in an analysis of the text.
Comment: I don't want to get into an argument, and I can see you take this personally. I have added a further citation to show that if the event did not occur, then the answer to this question is that the author portrayed what Jesus did.  As for Professor Ranke-Heinemann, she retired as Chair of Religious History after an illustrious teaching career, so more than just a "fancy title".
Comment: @JayarathinaMadharasan has twice stated I have not answered the question. I found and read some helpful meta pages, to see what I did wrong. I read that I am not required to affirm the truth of any Christian belief, so that's not a problem. I reread my answer to see if I went off-topic, but my answer describes what some Christian scholars say about this topic, so this seems OK. Being new here, I do not know how to open a chat room, but I invite you to do so and point me to it, so I can learn why U see my answer as not addressing question, with others able to join in and help me.

Why did Jesus turn water into wine?


plugin.properties and plugin.xml internationalization substitution

Question: I have an eclipse plugin that is suffering from failing to substitute strings in plugin.xml.
I'm building it with tycho, but I don't know if that has anything to do with it.
The resulting jar has plugin.xml and plugin.properties at top level.
For an example, in plugin.xml, I have
<code> <editor
        name="%editor.name"
  ...
 >
</code>
and then in plugin.properties:
<code>editor.name=Doxia APT Editor
</code>
But in the "Open With" menu in eclipse indigo, I see %editor.name.
What am I doing wrong?
Answer: Is it the only missing string?  If all of them are wrong, you may check if you correctly included the "Bundle-Localization: " key on your MANIFEST.MF file.
This key should have the properties file name as its value, without the ".properties" extension.


Asynchronous inputs to timing diagram

Question: I'm very new to hardware logic (and this site) but I'm trying to understand the exact use and duration of the asynchronous inputs clear (CLR) and preset (PRE) on flip-flop timing diagrams.  They seem to typically both be active-low triggered.  I know that CLR sends the Q outputs to 0, while PRE sends them to 1, both regardless of what edge the clock is on (if any).  What I'm not sure about, is the duration after the initial clear or preset.  In other words, does Q just go to 0 on clear but only when clear is first low, then can be dependent on the inputs (JK, T, D, SR) again?  Or does Q stay low for the entire duration of time that CLR is low?  Similarly for PRE, would PRE send Q outputs high for the entire time that PRE is high, or is it only initially when PRE first goes high? Thanks for your patience as I'm learning.
Answer: As you mention, asyncronous SET and RESET signals are often active low.  To simplify the explanation, let's assume we're doing a RESET.  (PRESET will work the same way.)
The Q output will be driven LOW as soon as the RESET is pulled low.
The Q output will remain LOW as long as the RESET is held low, regardless of other signals.
At the trailing (rising) edge of the RESET pulse, the Q output will remain LOW until the next clock, when it will reflect the state of the flip-flop.
Comment: ... And if you look closely, there is a RESET (or PRESET) recovery time in the data sheet. This is the minimum time from the end of RESET to the next clock edge for which the device is guaranteed to operate correctly.
Answer:
The TTL active low terms Preset and Clear (Pre,Clr) pre-date the identical terms Set and Reset (S,R) which are more common in CMOS and often "active high".
If both inputs are active is the only time when Q and Q_ are both high  i.e. not complementary.  ("active" meaning for above inputs in active state)

Set has priority over Q and Reset has priority over Q_ (read Q bar).

When the above is true, The 1st to go inactive determines when it's corresponding primary output toggles. (i.e. if S and R are both active and R is removed 1st while S is still active, then Q_ toggles from high to low to satisfy Set as still active.

Both being latched inputs, they can be removed as soon it enters the active state and may be removed immediately which is used in hand-shaking communication logic or to preset aynchronous counters quickly.
The smallest pulse may be generated by gating the either output(Q,Q_) and externally gated with the either input(S,R) so that the input condition is removed immediately after the  output goes active. (respectively) This is how Flip flops are used in edge-sensitive asynchronous phase detectors a.k.a Type II mixers in PLLs.

An example below of the guaranteed narrowest pulse one-shot generated using a FF and external gate to turn off the ClR input as soon as the output changes due to D being 1 and clocked in.

Asynchronous inputs to timing diagram


New domain vs Subdomain vs new Folder for each new project

Question: If I have a domain like http://example.com/ which would be the best to use for every new project I create. Would it be a subdomain http://exampleprojectname.example.com/ or a new domain http://exampleprojectname.com/ or a new folder http://example.com/exampleprojectname. Which one would be the best and good for seo.
Comment: There is already many questions and answers regarding the use of domains vs that of a sub directory or sub domain, please ensure you read the rules and faq before posting to avoid further disappointment. Additionally > http://webmasters.stackexchange.com/questions/3496/do-subdomains-help-hurt-seo
Answer: The answer is simple. Do you want each project to perform well on their own (completely) or do you want support between them? If you want the project to compete completely on their own with little to no bleeding/support from one to the other, then you want a sub-domain. If they are to support each other and have some relative relationship, then you want a sub-directory.


No mission icon to find Nadas freighter

Question: I'm working on finding Nada's crashed freighter for Null, but whenever I land at the approximate location, the icon disappears. I tried locating it by pressing "F" for my scanner but theirs no option for using the locator.  I can see the freighter, but since theirs no icon I have no idea which part I'm supposed to go to and what to do.  I tried going to the anomaly and coming back, quitting to the menu and back, but nothing works.  How do i get the icon to show?
Answer: As of a recent update, any time you are doing missions... The analysis visor will have to be switched to target sweep to find the precise location of your objective. It looks like this:

You need to have your active mission set, if done correctly it will be on the left hand side like in the picture and point you in the right direction.
Comment: I tried that but it says "no location service available" and doesnt do anything.  =(
Comment: You might have to do a scan first ('c' on PC)
Answer: I figured it out.  While my mission icon never did show, I went to the freighter and found the Terminal.  This is what you are looking for and it's not that hard to find once you realize that.  Once I started using the terminal the mission icon started working fine.  Finicky, but it worked.  Thanks to Rapitor, for trying to help!  Cheers!

No mission icon to find Nadas freighter


Tablet does not connect to the hotspot

Question: My Samsung tablet was working just fine. Now it does not connect to the Internet via our hotspot. It does not even scan and see the available connections. When I try to turn WiFi on, it turns ON momentarily and then again turns back OFF saying To see available networks, turn on wi-fi
Comment: What kind of hotspot are you trying to connect to?
Answer: This happened to me once and I just made a factory reset. However this did not work for a friend.

Tablet does not connect to the hotspot


Protocol composition

Question: I have been trying to wrap my head around different definitions of protocol security (stand alone, sequential composition, parallel composition, universal composition) and how the proofs of any of these cases are obtained. However, at current state I find it quite complicated. Can you recommend any good lecture materials or maybe survey articles that would help to get into this topic?
Comment: I assume you've read Canetti's "paper" that has already grown to a small book: http://eprint.iacr.org/2000/067
Comment: At least I have tried reading it. My hope was that maybe there is a more easily readable introduction material.
Comment: You got a view recommendations already, so hopefully there was something useful for you. But anyway, reference recommendations are offtopic here.
Answer: Protocols for Authentication and Key Establishment [1] By Colin Boyd is considered very good book. That has plethora of examples, proofs etc. in very understandable language and format.
Another book is Modern Cryptography Theory And Practice [2] by Wenbo Mao. Few chapters have very good introduction to designing protocols in attack-fix cycles.
and few more

Boyd, Colin, and Anish Mathuria. Protocols for authentication
and key establishment. Springer, (2003).
Wenbo, Mao. "Modern cryptography: theory and practice." Publisher: Prentice Hall PTR,
Copyright: Hewlett Packard (2004).
Cremers, Cas, and Sjouke Mauw. Operational semantics and verification of security protocols Berlin: Springer, 2012. This is an excellent single book that covers all the aspects needed in great detail and rigor.
Bella, Giampaolo. Formal correctness of security protocols. Heidelberg: Springer, 2007.
Comment: I could not see anything about the (e)CK model in the index of the first book. The eCK-model is from 2007 non-extended one is from 2001, however, the book is from 2003.

Protocol composition


Will it ever be possible to construct a neural network that could have the features of human brain?

Question: I have a question. Will we be able to build a neural network that thinks abstractly, has the creativity, feels and is conscious?
Comment: So basically an AGI (Artificial General Intelligence)?
Answer: Maybe in the distant future they could build a computer powerful enough to simulate the individual neurons of an entire human brain. Then they could carefully copy/paste the connectivity of a sample brain into the computer simulation.
Given that this extreme seems physically possible, it stands to reason that much simpler/smaller alternatives could be engineered in the future assuming continuous advancements in technology.


Create new linux account as a user without root access

Question: Is it possible to create a non-root Linux user account without being logged in as a root user and without using sudo?
Comment: Why do you want to do this - what is your need?
Answer: Boot up into a system rescue CD. Or, if your root account is locked, boot to single-user mode (add 1 to the end of the boot command).  Other than that, no. Could you imagine how insecure that would make a system?
Comment: @Simone You could make dozens of accounts so it's hard for the admin to kick you off the system. Or make a second account and store all your illegal files there. Or just make new accounts to get around per-user restrictions like disk quotas
Comment: I don't see any security threat in that. I just want to create an user account with the same privilege I have in my account while I'm logged with my account
Comment: @Simone A comment like this is likely to get you fired in any shop that actually has computer systems helping you make money.
Comment: @Kevin well even the way you describe it you will be creating accounts as user root. Not all systems allow login without root-password in runlevel 1. And the boot-process as well as the boot menu should be password protected on any halfway secure system.
Comment: @Nils Yes, but not the root of his system. My understanding of runlevel 1 is that it requires a password if and only if root has one, but it's possible I'm mistaken. And yes, the boot menu *should* be protected, but we all know that's not always going to be the case.
Answer: It requires writing in some files. Which happen to be writable only by root.
So use a setuid root binary like sudo or be root.
If the system is not being used, just mount the hard driver and edit manually the files you need, there should be binaries on the system to edit the password file/groups and such. I'm more a BSD user so I don't know the names but look for vipw/adduser/useradd/usermgmt/etc.
Are you sure you really need to do that? Managing user is part of the administrator's tasks, so root is the way to go. If someone else can modify system files, there's a security problem.
Answer: No. Generally speaking, the unix permission model only has two levels: root, and the rest. Root can do everything, and non-root users each have their own domain. Non-root users cannot create subdomains inside their security domain.
There is a way to create security domains as an ordinary user: run a virtual machine of some kind (VirtualBox, User Mode Linux, …). You can isolate applications running in the VM to your heart's content.
Answer: If the root user wanted to allow this, she could configure PAM to allow it, or even allow it by group membership.
By default, no it cannot be done and I'm not going to write a PAM example.
This is an admin decision and any admin confident (not sure that's the best word) enough to allow this, should be experienced enough to configure PAM without help.
Answer: samba has a mode that will create accounts "on the fly". I am not sure if your question is related to Windows-based authenticated access from "new" users.


Dropbox like service with git -- no with rsync and inotify

Question: Do you have any advice as how to setup a Dropbox like service using git?
Do you think git is the right tool for this?
I was thinking about using a git + rush solution what do you think about it?
Answer: Checkout this open source project: https://github.com/hbons/SparkleShare
From the project's README:

How does it work?
SparkleShare creates a special folder on your computer. You can add remotely hosted folders (or "projects") to this folder. These projects will be automatically kept in sync with both the host and all of your peers when someone adds, removes or edits a file.
Answer: If you own a remote server and you are running linux then you can simply have a folder that you rsync set it up as a 'every 10 seconds' chron job for example.
There was a thing you can install onto linux that gives you the mac time vault or windows shadow copies like feature. Have this running on the remote server.
This is by no means going to be as good as a service dropbox currently gives you, but it is free, save the server space...
UPDATE
Having read up more about how Git works (check out the wiki page, quote from Linus is top notch) seems all you would need is to get the remote sever, and set up a cron job that regulary commits your changes and downloads any updates, as this way you can share files as well as sync with multiple computers.
Not sure how secure Git is, can others just start reading it or do they need to know a password or something? in which case, run it in an encrypted partition.
Answer: Thanks thecoshman you got me into the right direction rsync.
The problem was that the cron job didnt seem a valid option I'd have liked to have a change notifier:
Enters: inotify
And here it is a wonderful blog entry for an Open Source Dropbox solution.
UPDATE:
There is a project on github which s the result of the blog post discussion it's called lipsync
Answer: I've developed a super simple script that use git and cron to sync folders among several linux computers.
It installs everything by its own or explains how to do it: install git on local machine and server, install public/private ssh keys, check sshd is installed...
I've put it on github:
https://github.com/photonOli/gitBox/


Difficulties with playing YouTube videos in Big Sur beta in Safari

Question: I was trying to play YouTube videos in Safari v14.0 (16610.1.23.1.3) in Big Sur beta, but it doesn't work, playing window is black and after click into it I get a message that an error occured. Does someone has solution for this one?
Answer: Okay guys, I solve the problem. It was causing AdBlock extension for Safari, I uninstalled it and installed AdGuard and now it works like a charm.
Comment: It's a beta version, so please make the developer of the plugin aware of the issue.
Comment: That's actually something Google has recently changed & all the ad blockers are rushing to catch up.
Comment: I'm getting this error on many youtube videos, but I don't have a single extension installed in Safari. Big Sur beta (20A5364e).
Comment: Oh, I didn't know that. Thanks for a new info :)


Ensuring performance of sketching/streaming algorithm (countSketch)

Question: I have implemented what is know as a countSketch in Python (page 17: https://arxiv.org/pdf/1411.4357.pdf) but my implementation is currently lacking in performance.
The algorithm is to compute the product SA where

A is an n x d matrix,
S is m x n matrix defined as follows:
For every column of S uniformly at random select a row (hash bucket) from the m rows and for that given row, uniformly at random select +1 or -1.
So S is a matrix with exactly one nonzero in every column and otherwise all zero.

My intention is to compute SA in a streaming fashion by reading the entries of A. The idea for my implementation is as follows: observe a sequence of triples (i,j,A_ij) and return a sequence (h(i), j, s(i)A_ij) where:

h(i) is a hash bucket (row of matrix chosen uniformly at random from the m possible rows of S
s(i) is the random sign function as described above.

I have assumed that the matrix is in row order so that the first row of A arrives in its entirety before the next row of A arrives because this limits the number of calls I need to select a random bucket or the need to use a hash library.
I have also assumed that the number of nonzero entries (or the length of the input stream) is known so that I can efficiently encode the iteration.
My problem is that the matrix should compute (1+error)*||Ax||^2 <= ||SAx||^2 <= (1+error)*||Ax||^2 and also have the difference in frobenius norms between A^T S^T S A and A^T A being small.  However, while my implementation for the first condition seems to be true, the latter is consistently too small.
I was wondering if there is an obvious reason for this that I am missing because it seems to be underestimating the latter quantity.
I am open to feedback on changing the code if there are obvious improvements to be made.
nb. If you don't want to run using numba then just comment out the import and the function decorator and it will run in standard numpy/scipy.
import numpy as np
import numpy.random as npr
import scipy.sparse as sparse
from scipy.sparse import coo_matrix
import numba
from numba import jit

@jit(nopython=True) # comment this if want just numpy
def countSketch(input_rows, input_data,
                      input_nnz,
                      sketch_size, seed=None):
   '''
   input_rows: row indices for data (can be repeats)
   input_data: values seen in row location,
   input_nnz : number of nonzeroes in the data (can replace with
   len(input_data) but avoided here for speed)
   sketch_size: int
   seed=None : random seed
   '''
   hashed_rows = np.empty(input_rows.shape,dtype=np.int32)
   current_row = 0
   hash_val = npr.choice(sketch_size)
   sign_val = npr.choice(np.array([-1.0,1.0]))
   #print(hash_val)
   hashed_rows[0] = hash_val
   #print(hash_val)
   for idx in np.arange(input_nnz):
       print(idx)
       row_id = input_rows[idx]
       data_val = input_data[idx]
       if row_id == current_row:
           hashed_rows[idx] = hash_val
           input_data[idx] = sign_val*data_val
       else:
           # make new hashes
           hash_val = npr.choice(sketch_size)
           sign_val = npr.choice(np.array([-1.0,1.0]))
           hashed_rows[idx] = hash_val
           input_data[idx] = sign_val*data_val
   return hashed_rows, input_data

def sort_row_order(input_data):
   sorted_row_column = np.array((input_data.row,
                                 input_data.col,
                                 input_data.data))

   idx  = np.argsort(sorted_row_column[0])
   sorted_rows = np.array(sorted_row_column[0,idx], dtype=np.int32)
   sorted_cols = np.array(sorted_row_column[1,idx], dtype=np.int32)
   sorted_data = np.array(sorted_row_column[2,idx], dtype=np.float64)
   return sorted_rows, sorted_cols, sorted_data

if __name__=="__main__":
   import time
   from tabulate import tabulate

   matrix = sparse.random(1000, 50, 0.1)
   x = np.random.randn(matrix.shape[1])
   true_norm = np.linalg.norm(matrix@x,ord=2)**2
   tidy_data =  sort_row_order(matrix)

   sketch_size = 300
   start = time.time()
   hashed_rows, sketched_data = countSketch(tidy_data[0],\
                                            tidy_data[2], matrix.nnz,sketch_size)
   duration_slow = time.time() - start
   S_A = sparse.coo_matrix((sketched_data, (hashed_rows,matrix.col)))
   approx_norm_slow = np.linalg.norm(S_A@x,ord=2)**2
   rel_error_slow = approx_norm_slow/true_norm
   #print("Sketch time: {}".format(duration_slow))
   start = time.time()
   hashed_rows, sketched_data = countSketch(tidy_data[0],\
                                           tidy_data[2], matrix.nnz,sketch_size)
   duration = time.time() - start
   #print("Sketch time: {}".format(duration))
   S_A = sparse.coo_matrix((sketched_data, (hashed_rows,matrix.col)))
   approx_norm = np.linalg.norm(S_A@x,ord=2)**2
   rel_error = approx_norm/true_norm
   #print("Relative norms: {}".format(approx_norm/true_norm))
   print(tabulate([[duration_slow, rel_error_slow, 'Yes'],
                   [duration, rel_error, 'No']],
                   headers=['Sketch Time', 'Relative Error', 'Dry Run'],
                   tablefmt='orgtbl'))

Comment: "... the latter is consistently too small_" does that mean it is not working correctly?
Comment: Should `(1+error)*||Ax||^2 <= ||SAx||^2 <= (1+error)*||Ax||^2` read *(1 **-** error)\*∥Ax∥² ≤ ∥SAx∥² ≤ (1+error)\*∥Ax∥²*?
Answer: as suggested by @SamOnela, code not working is off-topic. for your performance issue, you can group your calls to choice at the beginning of your function
   hash_vals = npr.choice(sketch_size, input_nnz)
   sign_vals = npr.choice(np.array([-1.0,1.0]), input_nnz)

and use it later in your code this way:
       hashed_rows[idx] = hash_vals[idx]
       input_data[idx] = sign_vals[idx]*data_val


What happens to inventory when you die under ice

Question: Say someone dies underwater with ice blocks above them. What happens to the items that person had? Where do the items go?
Answer: Assuming vanilla Minecraft, items only remain on the ground for 5 minutes without any mods. If it took you longer than 5 minutes to get to your place of death, your inventory is gone, sorry.
Note that there are gravestone or gravechest mods out there that will spawn a chest with your items or a gravestone that will last until you break it to get your items back.
Answer: The location of your items depends on many factors. One factor is the items' "density". Some items will float and others will sink. Another factor to consider is bubble columns, as they will cause all (dropped) items to rise or sink, depending on the bubble column. An additional factor includes dolphins and other players, as they can move items. So, if the items sink, they'll be at the floor of the body of water. If they float, they will be waiting just below the ice you died under.
Answer: Your items could might be under the right under the ice, or at the bottom of the water. If the items cannot be found, immediately save and exit your world so that you don't run out the timer.
Note: The items might be a few blocks away if you didn't look well enough, either above the ice or underneath it. Sometimes, the items will go flying a few blocks away. I would suggest taking a look around both places, above or below.


What's a good way to run a virtual copy of Ubuntu on Windows 7?

Question: I have a mathematical program that runs on 64 bit Ubuntu. I need to run it on my Windows 7 workstation, preferably without having to install Ubuntu instead of Windows, because this is a short term need. Is there a way I could run 64-bit Ubuntu as a virtual machine on my Windows 7 box?
Answer: You can download VirtualBox to run a virtual copy of Ubuntu.
Download a disk image of the Ubuntu 64-bit install CD here. Then open VirtualBox and create a new machine with the disk image as the start up disk.
I use this to run Ubuntu on Windows 7 every day and it works very well.
Comment: Are there alternatives to VirtualBox for Windows users who want to run Ubuntu inside a VM? VirtualBox doesn't currently support Windows 10 :(
Comment: I don't know of any that are free and as fully featured. VMWare is excellent, but expensive. Have you tried running VirtualBox on Windows 10? I know the site says it's unsupported, but it might still work.
Comment: Just adding this: if your CPU can do this (it likely does) you will be able to run 64-bit Ubuntu in a Virtual Box even when your Windows 7 host is 32-bit only.
Answer: You can use VirtualBox and if you really just want Ubuntu for the software i.e. rather than for the whole Unity interface based experience, you might consider Lubuntu instead.
http://lubuntu.net/
Lubuntu is simply the official LXDE version of Ubuntu and while its spartan blue/grey looks may not win any beauty contests, it does work a lot better than other forms of Ubuntu in VirtualBox.
LXDE is a desktop environment designed for less capable hardware and therefore it is quite suited to virtualisation software, which typically isn't able to use your hardware as efficiently as a bare metal installation.
Answer: This really isn't an Ubuntu specific question, but you need to install Cygwin inside your Windows 7 session. Cygwin is a Linux emulator. You can then run your Linux executable from within your Cygwin session.
http://www.cygwin.com/install.html
Comment: No, **that is a common misconception about Cygwin**. Cygwin does *not* (ever) run Linux executables. As is [prominently stated on the Cygwin home page](http://cygwin.com/), "Cygwin is not... a way to run native Linux apps on Windows. You must rebuild your application *from source* if you want it to run on Windows." (emphasis in original) Cygwin **is not a Linux emulator**. Consequently, this really does not answer the question that was asked--Cygwin does not facilitate running Ubuntu or any other GNU/Linux distribution (or *any* non-Windows OS) on Windows.


Looking for lyrics of a soundtrack from the movie A Clockwork Orange

Question: I am looking for the lyrics to "Ode to Joy". A recording is at this link: https://m.soundcloud.com/user394434059/05-march-from-a-clockwork-orange-ninth-symphony-fourth-movement-abridged
Answer: Beethoven's Symphony No. 9, Fourth Movement - An Die Freude ("Ode to Joy").
Full lyrics and English translation are on the Wikipedia page linked above. The lyrics, which are in German, are from a poem by Friedrich Schiller.
Here's a video with lyrics and English translation following the symphonic version:
https://www.youtube.com/watch?v=4pbMUEHvoAo

This track and much of the synthesizer music on that soundtrack was arranged and performed by Wendy Carlos, who is probably best known for "Switched-On Bach".  She went on to work with Kubrick again, composing much of the soundtrack for "The Shining".
Comment: Wendy Carlos' performance is probably the human voice processed through a vocoder modulating the tones of Carlos' synthesizers, with the timbre and lyrics deliberately obscured for effect.
Comment: Wendy Carlos is famous for not permitting any of her recordings to be made available on YouTube, for streaming online, or for sale as digital downloads. Some people have attempted to post her recordings on YouTube or Soundcloud, but as soon as she identifies them, she has them taken down for copyright violation. YouTube clips that people have uploaded have been replaced by YouTube with generic public domain orchestral music. This SoundCloud clip you have found will probably be deleted quickly as a result.
Comment: I would add that the soundtrack album for A Clockwork Orange is long out-of-print as a CD or as vinyl; your only chance of purchasing it is to find a used copy for sale in a used record store.
Comment: Carlos also released an album of music composed for the film that ended up not being used in the film itself, called *Walter Carlos' Clockwork Orange*, on vinyl in 1972. That is also long out of print. There was a very limited re-release on CD (using the name Wendy and not Walter) in 1998, which is likewise long out of print. Several used record dealers on Amazon offer used copies they are selling for between US $36 and $80. The complete title of the re-release is *A Clockwork Orange: Wendy Carlos' Complete Original Score*.
Comment: The human vocals for the track were provided by [Rachel Elkind](http://www.wendycarlos.com/rachel.html).  Great info, thanks!  Guess I scored on that LP - 99 cents at the thrift store.
Comment: guy you can not even imagine how a big favor you did.. thank you very much


What is the type of hinge used in fold-down car tv's?

Question:
I am trying to find out what type of hinge or mechanism is used in fold down car TV's. I need to buy one for a project I'm working on but dont know the name. See picture above.
Comment: What is your project? Orientation, mass, number of electrical signals which must pass thru hinge, number of "hold angles" ?   Please don't post *how* you want to solve, but **what** you want to solve.
Comment: Consider looking for laptop lid hinges. These should be easier to obtain (as replacement parts for laptops) and likely display the same behavior.
Answer: These are not usually simple hinges - they are often designed with cams etc to give a specific movement - so are usually specific to the item.
Think of kitchen cupboard hinges - the simple ones are easy to replace, but some have extending movements so doors can move out to clear other doors...
You may find a hinge that does the movement you require and then you will need to re-manufacture it to cope with the load you will be applying...
Comment: This particular one seems to be simple pin joint. Athough if it is machine actuated it probably really is a fourbar. But yeah eurohinges are typically sixbar mechanisms.
Answer: The hinge will be similar to the one for the laptop monitor.

You can search "hinge for LCD monitors" such as this page.


Once I log into Stackoverflow, can I get Google to somehow automatically log off my account?

Question: I use Google as my OpenID provider. Once I log into Stackoverflow with my gmail account, can I get Google to somehow automatically log off my account?  I prefer not to have my personal google account always logged in. It's not a big deal going to gmail and clicking log off, but if there is a simpler way that would be good.
Comment: Is this really a meta question?
Comment: It's a feature request, else I would have closed it as being off-topic on Super User
Answer: No. StackOverflow cannot in anyway affect Google's cookies.
StackOverflow can only control the cookies for stackoverflow.com, and subdomains. Because Google is a completely different domain, StackOverflow is unable to add, modify, read, or delete their cookies.
Answer: If you don't like this, one of the nice things about StackOverflow is that you can use the alternate OpenID feature to switch your account to a different OpenID provider that has the behavior you want.
Answer: It'll just be an AuthToken. Only of use to connect your browser to your Google ID. You're not logged in to Google in the normal sense.
Answer: Unfortunately this, by my understanding, is behaviour as designed.
The point of OpenID is that you are able to login using one set of credentials and remain logged in to multiple sites using the same account.
If you do not want accounts to be linked in this way then you need to separate them rather than have them be associated via OpenID or similar schemes.


Having trouble installing pyWin32 on my windows 10 operating system based computer

Question:
Why will it not install? I thought I followed the correct procedures
Comment: The error message is right there on the screen: `pyHook.whl is not a valid wheel filename.`
Comment: Why are you trying to install from a wheel file anyway?  All of the Windows packages I see on `https://www.python.org/downloads/release/python-352/` are .ZIP or .EXE files.
Comment: I am focusing on the second part of  the terminal, not the line of the terminal with pyHook.whl. I went to this site to download my packages(http://www.lfd.uci.edu/~gohlke/pythonlibs/) and I did not see any executable files. I tried to unzip the python module file with 7zip but no luck
Comment: Are you trying to install Python itself, or a specific python module?
Comment: a specific python module, particularly, pywin32 and pyHook
Answer: Just use bounding quotes for the full path of .whl file.
pip install "C:\...full path with spaces\pywin32-...-win_amd64 (1).whl"

Of course make sure pip install wheels was run first.
Alternative way is using easy_install (not necessary to download the installer manually):
easy_install.exe https://github.com/jmdaweb/TWBlue_deps_windows/raw/master/x64/pywin32-220.win-amd64-py2.7.exe

But the second way may cause problems with py2exe if you have plans to use it. Maybe pip install pypiwin32 is OK for you (it will install pyWin32 build 219, should work just fine for most cases).
Comment: where to get easy_install.exe from >
Comment: Usually it can be found in C:\Python27\Scripts\ or something like that. It's included into Python distribution. Even for the very basic one from python.org.


can I just double the orange flower water?

Question: I'm making orgeat and it calls for 1/2 a tsp each of orange flower and rose water. I found the orange flower water in my cupboard and I don't have any store near me to get rose water. Would it be ok to just omit the rose water and use a tsp of orange flower water?
Answer: You *can*, but...
Orange blossom water can very easily overpower everything else in your syrup and even your cocktail, for that matter.
So I'd recommend going slow with it, taste-testing both the plain syrup and mixed into a cocktail (an army & navy has a bit less going on than a mai tai, but it's probably best to test with whatever cocktail you enjoy most.)  You can always add a few more drops of orange blossom water.
Answer: It will taste different and some would say that it is not what they expect from orgeat. But nothing will go 'wrong'.
Comment: I mean I'm the only one drinking it and ive found recipes that only call for orange flower water.


Jazz theory: In progression II7-V7-I, can I make tritone substitute with different kind of Altered V7?

Question: Like F7b9 to B7+5 ; F7alt to B7+11? I meant any kind of different altered dominant seven, not only some particular ones like F7alt to B7 , F7b9 to B7b9, etc
Answer: Tritone substitution relies on two factors - the 3rd and the 7th. Let's take C7>F. C7 = C E G Bb. The tts is F#7, = F# A# (Bb) C# E. The 3rd of C7 becomes the b7th of F#7, while the b7th of C7 takes the place of the 3rd of F#7. Simple substitution - hence the name. Other notes may or may not feature in each chord, but those two need to. So, as far as I know, 7b9 won't make a lot of difference to tts, as any other altered chord, as long as 3 and b7 become b7 and 3.
Bottom line as always is try it, if it sounds good in the context, then use it.
Answer: Short answer: you can make almost any alterations you want.
Let's say the progression is | Cm | F7 | B♭∆ |. Let's also say that we don't have to worry about whether the chord substitution will clash with the melody or will clash with another soloist. It's extremely common to alter the F7. For example, you could add a ♭13, a ♭5, a ♭9, or a ♯9. You can combine two of these together, and you can do things like play a ♭9 with a ♮13, or play a ♮9 with a ♭13. There are many possible ways to alter the 5, 9, and 13 of the F7 chord.
Each of the altered F7 chords will sound great with a B in the bass. When performing the tritone substitution, it's not necessary to think in terms of the B7 chord at all--each alteration to the 5, 9, or 13 of F7 will correspond to a note in the B7 chord. For example:
F7 chord       B7 chord
   ♭9        →      5
   ♯9        →      13
   ♭13       →      9
   ♭5        →      1
And non-altered tones from the F7 chord will become alterations of a B7 chord.
F7 chord       B7 chord
   ♮9        →    ♭13
   ♮5        →    ♭9
   ♮13       →    ♯9
In addition to making alterations (or not making alterations) to the 5, 13, or 9, it's also possible to use a ♯11 chord. F7(♯11) implies a natural 9th and 13th, not an altered 9th or 13th. One common voicing for F7(♯11) involves using a G maj upper structure triad. For example, on piano, one could play the A-E♭ with the left hand and G-B-D with the right hand. The natural 9th and 13th of F7 will produce a B7(♯9♭13) chord when the base plays a B instead of an F. And equivalently, if you're thinking in terms of B7, playing B7(♯11)--played with a C♯ maj upper structure triad--would be the same as playing F7(♯9♭13) if the root were an F instead of a B.
Personally, when playing a tritone substitution, I usually think in terms of the original F7 equivalent chord. This is mostly a personal preference. But whichever way you think about it, if your alterations sound good with a normal F in the bass, then it will also sound good over the tritone sub.
Comment: I'm not sure what you mean by "F7(#11) will become B7(#9,b13)" and vice versa. The #9 of B7 is a 'D' which is the 13 of F. Maybe you mean B7(b9,b13), even though the 'C' (b9 of B7) would usually be avoided in an F7(#11).
Comment: @MattL., the #11 chord implies a natural 9th and 13th as opposed to a altered 9th or 13th. An extremely common voicing uses a G maj upper structure triad. These upper structure notes (`G`-`B`-`D`) are the b13, 1, and #9 (respectively) of `B7`. Similarly, if one were to play `B7(#11)`, the C# maj upper structure triad would produce the b13, 1, and #9 of `F7`. I will edit to clarify. Also, I'll fix the auto-formatting guitar tab.


Decrease in no. of page views on GIS SE

Question: Page views on GIS SE have been significantly reduced from ca. mid of May this year: what is the reason for that?
Answer: Although framed as a New Visits rather than Page Views question, the reason for this has been discussed on Meta Stack Exchange as Why has there been such a huge drop in "new visits" since May 9th, 2022, across multiple sites?
Answer: There is a cycle on message boards and forums and social media sites. When one is set up, it is a lot of fun to post there. Then various trolls take it too far and there is a call for stricter moderation. Then the moderators start to become more strict. Eventually it is not any fun to post on the site, so even the regular users stop posting there. They move on to a newer site that has less moderation. Then the rules and moderation proliferates at the new site, and the cycle continues.
I get it, moderation is hard and thankless. It is also necessary. But at the rules grow more numerous engagement often goes down. It's a pattern. Though it might not explain the precipitous drop in that chart, it is a real effect.

Decrease in no. of page views on GIS SE