Do you need to manually level the bed with a BLTouch? Adhesion issues with Ender 5 and BLTouch 1.3

Question: I've just installed a BLTouch on my Ender 5 Pro and updated the firmware to 184.108.40.206 and enabled BL touch. I can send a G29 which probes all the points correctly, I also get a readout of the results in OctoPrint terminal but when it puts a first layer down the filament does not adhere to the bed. I also end up with a large clump on filament stuck to my nozzle afterwards.
I've set the Z probe offset while the nozzle was in the center of the bed, and had a good grip on the piece of paper under it while setting it. I stored settings afterwards. I can't actually tell if the BL touch is even doing anything.
Do I need to manually level the bed before using the printer with a BLTouch? It currently has not been leveled since I assembled the printer. I guessed the BLTouch would handle this for me and I wouldn't need to level the bed ever?
These were the results from my G29:
-0.218, -0.148, -0.116, -0.088, -0.084
-0.194, -0.136, -0.115, -0.061, -0.020
-0.138, -0.035, +0.030, +0.091, +0.107
-0.008, +0.062, +0.129, +0.191, +0.261
+0.160, +0.261, +0.339, +0.411, +0.469

Comment: Bed leveling it not magic, you still need to level the bed out as good as you can.
Answer: yes
Even with auto mesh bed leveling, you ought and should level the bed to a good degree to make the leveling not only more efficient: the mesh bed level is to work out small dimples and hills in the bed, bot to work with a crooked or heavily misaligned bed.


How to confirm the working of Remote Storage with Magento Cloud?

Question: I have successfully configured and synced the media files to the Amazon S3 bucket(as mentioned in https://devdocs.magento.com/guides/v2.4/config-guide/remote-storage/config-remote-storage-aws-s3.html) but still, the product images are getting loaded from the media cache folder. How to confirm whether Remote storage is successfully installed or not.Any idea?
Answer: Magento recently added this documentation, https://experienceleague.adobe.com/docs/commerce-operations/configuration-guide/storage/remote-storage/cloud-support.html?lang=en
Answer: You can check if newly uploaded product images in magento are visible in S3 or not. For me, when I restarted magento then it starts uploading to S3.


toDataURL canvas drawImage

Question: I'm trying to make an app that captures screenshots from webcam feeds. I have a bunch of curated URLs of webcams that I'm trying to load into a canvas which I can then save using toDataURL. The problem is, when I use drawImage from a URL with a different origin, Chrome and Firefox throw security errors. Is there any way to get around this / is there something else I can use?
Answer: You can try to use limited proxy (nginx will be smart and powerfull solution) at the same domain or to make a server-side script which will prepare and/or cache images (if data reusable, need some protection, etc). In specific conditions there available CORS

toDataURL canvas drawImage


"Food safety is of utmost importance" Vs "Food safety is paramount."

Question: I read one article about food safety. It tries to state that food safety is the most important to the government. The writer put "Food safety is of utmost importance". But I think "Food safety is paramount." is ok too and would be better. Which one would make the sense to a native speaker?
Comment: Native Speaker (US). Both sentences carry similar meaning as well as register. When I hear the word "Paramount" my mind goes to the film studio. I wonder if anybody else feels that way. I don't have any other word connections with the phrase "utmost importance".
Comment: I would write this as "Food safety is of *the* utmost importance." (AmE)
Answer: Let us look at a definition of paramount.

paramount
  1. Of chief concern or importance

So both examples make sense.
I would not say one is better than the other. Both constructions seem like common ways that people, especially companies/managers/authorities/etc, use to express that something is highly/most important.
So it really comes down to a matter of style. In my opinion, "Food safety is of utmost importance" really sounds like a cliche, scripted line from a manager or CEO, especially after a scandal regarding their food handling procedures. "Food safety is paramount" (by itself) sounds less scripted to me.
Answer: As others have noted, the two sentences have practically identical meaning.
"Paramount" is, I think, a less-commonly used word, so maybe fewer people would understand what it means.


Remittance to India from US in an Indian account?

Question: I am Indian citizen working in the US on a non-immigrant work visa. I have a regular savings account in India as well but I dont have an NRE/NRO account. So, will my remittance send to India account be taxable? I have already paid taxes on my income in the US.
Answer: Tax does not depend on whether you transfer the funds to India or keep in US.
If you have spent less than 182 days in a given financial year, then you are treated as "Non-Resident" [NRI] in India. If you are NRI, you need not pay tax for income earned outside India. If you are NRI, you should not be holding Savings account these need to be converted into NRO.
If you have spent more than 182 days in a given financial year in India, you are "Resident" and have to pay tax on your Global Income [whether you transfer funds to India or Not is not relevant]. You can claim the rebate to the extent of taxes paid in US.


Unable to use a live usb.

Question: Update to 64-bit 12.04LTS fails. I remade the LiveUSB once using Startup Disk Creator, and twice using unetbootin. I then, thinking it was the USB, used a different one using unetbootin. Also a failure. I have an HP 2000-2d69NR Notebook PC, 1.75GHz AMD E2-2000 CPU, 4GB RAM, AMD Radeon HD 7340 Discrete-Class graphics, 500GB HDD with Ubuntu 12.04LTS amd.
Answer: From what I understand, you can't boot into the live CD, right?
In your bios, try to disable UEFI boot, and set it to Legacy mode. Disable safe booting, too. Also, make sure that USB is at the top of the boot list, I always forget that :)
If you mean that the update starts, but fails, you would need to provide provide more information on your problem, your question is a little unclear :(
Comment: Couldnt disable UEFI, all options were in uefi. somethingx4, somethingx6 and somethingx4+6, which is the one i was on. I set it to legacy mode and i did what it told me then it just booted back into the os, i couldnt find where to take off safe boot either. usb is at the top of the list but no avail. Also your understanding is correct.
Comment: scratch that, i was able to find secure boot and i disabled it. and IPv4 IPv6 and IPv4x6

Unable to use a live usb.


What's the easiest way to deal with project configuration files?

Question: It's very common to have at least one configuration file in any project. Every time I share project with git, I have the same problem with:

sensitive information (each developer have different DB passwords etc)
task specific information (when developer works on certain task where one needs to change some settings)

Obviously, configs have to be ignored somehow to prevent developer specific data to flood main repository. Now there are several ways I used to use, each with some flaws:

.gitignore the config files

the most basic way
when developer clones repo, config file is missing and one has to find out where configs were recreate them

config file isn't ignored. It contains some dummy info and each developer either untracks and puts it to his .git/info/exclude or set git update-index --assume-unchanged ... to the file

files are available for anyone who clones repo
it contains advanced techniques which could confuse people that work with git for the first time
when someone commits config files by accident, it won't allow people to pull/fetch (as excludes don't work the same way as .gitignore)

distribute config files suffixed with, for example, _original while having the real files in .gitignore. Each developer then renames files to real names

files are available for anyone who clones repo
one has to search for all configs throughout application and rename them

Are there any other, possibly, better ways to handle this? I suspect I'm missing something, some plugin at least.
Comment: http://stackoverflow.com/questions/5132152/when-you-have-secret-key-in-your-project-how-can-pushing-to-github-be-possible could also help here.
Comment: ok, I have added as an answer details about the filter driver option then.
Comment: Hi all, what does this statement mean? `when someone commits config files by accident, it won't allow people to pull/fetch (as excludes don't work the same way as .gitignore)`
Comment: Nothing anymore from what I've tried. If someone pushes excluded file by accident, pull on other machine seems to overwrite the excluded one by one from upstream. At least with my git 2.5.4. Not sure if it ever worked differently.
Answer: Filter drivers are the "automatic" way of implementing option 3, as detailed in "when you have secret key in your project, how can pushing to GitHub be possible?":

The smudge script will, on checkout:

detect the right config files to modify
fetch the information needed (best kept outside any Git repo) and will replace the template values by the actual one.

From there the developers can make any kind of modification they want to those config files.
It won't matter, because the clean script will, on commit, restore the content of that file to its original (template) value. No accidental push there.
Comment: @Ondrej: the smudge script should be referenced by the user `PATH` or should be accessible through a common shared directory (shared amongst the developers, if we are talking about an group on the same LAN). **It doesn't change commits**. It only change the content of file upon checkout. And the clean script change their content just before commit.
Comment: I like this one best so far. Where would this smudge script be placed? As much as I understand, it should be placed on machine where central git repo is placed, but then how would it detect incoming commits that should be changed back to normal?
Comment: @Ondrej: See http://stackoverflow.com/questions/2316677/can-git-automatically-switch-between-spaces-and-tabs as an example, but remember that those scripts are based on the *content* of the file, not their name or path: read carefully http://stackoverflow.com/questions/2562523/using-git-to-work-with-subversion-ignoring-modifications-to-tracked-files/2562678#2562678: it was about using filter driver to put the *path* of the file within the file content itself, and that is not possible: a filter driver has only the content of the file as input. Not its name or path.
Answer: The way we did it on the last project i worked on was to have a master config file that loaded a users local config file if it was present which could overwrite the defaults set in the master if specified and declared its own config info if not present in master. The local file was added to gitignore. That way all common stuff could all be shared and some config always present and each developer can modify their local.
Comment: This, plus a README file explaining where to put the local config file.
Answer: Since it took me a while to figure out a working solution with @VonC 's hints, here's a full example of how to ignore passwords with a git clean filter in an Objective-C header file.

Assume you have a default config script named Config.h containing this
// Change "12345" to your password
#define kPass @"12345"
#define kConstant 42

Create a script hidepass.sh that matches the critical line(s) and prints the default line instead
#!/bin/sh
awk '{ if (/#define kPass/) print "#define kPass @\"12345\""; else print $0; }'
exit 0

Make the script executable and add it to the repo
Tell git to filter your config file by adding this line to .gitattributes (also add .gitattributes to your repo)
Config.h filter=hidepass

Tell git to use the hidepass.sh script for the hidepass filter during clean:
git config filter.hidepass.clean ./hidepass.sh

That's it, you can now change the password in Config.h but git will not commit this change because it always replaces that line with the default line on checkin.
This is a quick solution for a one-line password, you can go crazy and e.g. end the lines to be ignored with a special string and check for lines with that string.
Answer: In projects I have been, we have a default config, and developers have their own config at a particular location outside version control ( convention over configuration ) - the values from latter are used to override those in the former.
We started using encryption for sensitive details in the config: Handling passwords in production config for automated deployment
In case of git, you can look at git attributes filter attribute to do both the replacement of local values and decryption of sensitive values in an automated way.
You can also have submodules which have say the production.yml and with restricted access to the submodule repo.
Answer: One thing I can think of is similar to method 2 and method 1 above. Where you have a directory where you store complex things that are unique to the site such as directories for config files, user uploaded files, etc.
You keep just the config file itself out of version control, but then you have a dummy copy that is named slightly differently from what the site actually uses and this file contains detailed instructions as to the config parameters and to make a renamed copy.
For example, lets say you have a "site_profile" directory. In this directory you create a file called "README.settings.php" along with a "files" directory that contains user uploaded files (from both admin and front-end users). All of this is under version control.
However, the site will run its settings from "settings.php" which won't exist in here. But if you were to rename the "README.settings.php" to "settings.php" then you would have the config file you need (after you put in your custom settings of course).
This will allow you to tell the other developers what they need out of their config file while keeping your own config file out of the mix. Just set your config file to be ignored or never do a blanket commit for that directory and lower.
Its what we do with Drupal sites where I work and it works really well.
Answer: For the two cases you mention:

sensitive information (each developer have different DB passwords etc)
Write your scripts to so that these sensitive files are stored in the developer's home directory, rather than in the project directory.
task specific information (when developer works on certain task where one needs to change some settings)
I usually have the default settings checked into the repository, and then when you prepare your commits, you can easily check if you've modified any of those settings, and revert them before you commit.
Answer: I saved my local config changes to a git stash. I use git stash apply rather than pop, so that I never remove it from the stash queue. That way I can use reset --hard whenever I feel like it.
Answer: A lot of good options listed.
A few more options to mention:

Add all configs to .gitignore. Then have a separate git project, with the just the configuration files. (Keep this GIT #2 in a totally different folder.) In this GIT #2, make a few scripts similar to apply-config /path/to/my_git1, save-config /path/to/my_git1 which copy in, or save configuration files for the main GIT repo.

I prefer this to using submodules. I've found working with submodules cumbersome across a large team.
You can then track configurations, or use multiple GIT repos for things like production settings, debug settings, more optimized settings, etc.
Uses one tool (GIT) that everyone understands.

I like the idea of looking in the home folder for sensitive things like DB connection info. (Mentioned by @avh)
For devOps, you may want to consider things like Ansible / Salt / Chef / Puppet for automating deployments and settings.
Answer: Having no experience with Git, but having dealt with the same issues in other contexts (Hibernate login creds in a Spring JUnit suite, or ANT scripts), for anything that is user-specific or depends on a user's local environment:

Have a README listing those dependencies and how to configure your local env to run the script.
Replace those dependencies in your conf with calls to system properties, or some framework way to pull in external values.  In an ANT script, for instance, you can replace strings with <sysproperty key="jdbc.username" value="${jdbc.username}"/>, where jdbc.username is a system variable (that you can set in Eclipse).

Developers can check in whatever they want, because the conf is user-agnostic.
Answer: Another very common option, popularized by The Twelve-Factor App, is to not have any configuration variables hardcoded into files, but rather load them from environmental variables. This way, the files in repository don't need any special treatment.


Passing custom string into a Salesforce email template.

Question: I've stumbled upon a problem at the final stage of a new feature I was building (as always)
I need to pass in a custom string into a salesforce template, however there doesnt seem to be a way of doing this through the standard methods.
I'm passing in a contact ID, to email the correct user and name to personailse the email. But I need a string to be passed to the template which is completely unrelated to the contact record, and need to be dynamic. So I cant just put it in the template.
Is there a way? I know i cant pass in a custom object as it needs to be a contact, user or lead id to email a user.
Can you help?
Here is the code if you need to see it:
public static void sendSingleMail(id objId, ID templateId, string fromaddress) {

    Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
    mail.setReplyTo(fromaddress);
    mail.setTemplateId(templateId);
    mail.setTargetObjectId(objId);
    mail.saveAsActivity = false;
    mail.setReplyTo(fromaddress);
    mail.setSenderDisplayName(fromaddress);

    ErrLogger.logger('Email being sent to :');
    ErrLogger.logger('objId found:  ' + objId);
    ErrLogger.logger('templateId found:  ' + templateId);
    ErrLogger.logger('fromaddress found:  ' + fromaddress);

    Messaging.sendEmail(new Messaging.SingleEmailmessage[] {mail});
}

Answer: I've done something similar in the past, but it requires that you manually do the template merge field lifting. Here is an example of how you could do it below.
Since you are manually doing the merging in the template, you can put any kind of merge field into your template that you'd like. In this example, I'm pretending there is a custom merge field {!myCustomString} in the email template for your custom string you want to insert.
I've also assumed below that you have a merge field for first name {!Contact.FirstName} in the subject and in the body of the template. If you have other fields, you would need to include the fields in the contact query and then to the string replace for each of those fields.
public static void sendSingleMail(Id contactId, Id templateId, String fromAddress, String myCustomString){

    // grab the email template
    EmailTemplate emailTemplate = [select Id, Subject, HtmlValue, Body from EmailTemplate where Id =: teamplateId];

    // grab the contact fields we need. This assumes we are emailing a contact.
    Contact c = [Select Id, FirstName FROM Contact WHERE Id=: contactId];

    // process the merge fields
    String subject = emailTemplate.Subject;
    subject = subject.replace('{!Contact.FirstName}', c.FirstName);

    String htmlBody = emailTemplate.HtmlValue;
    htmlBody = htmlBody.replace('{!Contact.FirstName}', c.FirstName);
    htmlBody = htmlBody.replace('{!myCustomString}', myCustomString);

    String plainBody = emailTemplate.Body;
    plainBody = plainBody.replace('{!Contact.FirstName}', c.FirstName);
    plainBody = plainBody.replace('{!myCustomString}', myCustomString);

        //build the email message
    Messaging.Singleemailmessage email = new Messaging.Singleemailmessage();

    email.setReplyTo(fromaddress);
    email.setSenderDisplayName(fromaddress);
    email.setTargetObjectId(objId);
    email.setSaveAsActivity(true);

    email.setSubject(subject);
    email.setHtmlBody(htmlBody);
    email.setPlainTextBody(plainBody);

    Messaging.sendEmail(new Messaging.SingleEmailmessage[] {email});
}

Answer: I would recommend you take a look at Visualforce Components.
<apex:component controller="DynamicContent">{!dynamicContent}</apex:component>

public with sharing class DynamicContent {
    public String getDynamicContent()
    {
        return 'Something dynamic ' + System.today();
    }
}

Then in your Visualforce Email Template reference the new component via...
<c:DynamicContent/>

You can also pass parameters to the component, if you need context from the target record.
Answer: I provided my process before on this answer: Using APEX to assemble HTML Letterhead Emails
using regular expressions and a Map <\String,String> you can build your own mail merge process that works pretty well.
Answer: You could use a Visualforce email template. That way you have an Apex controller that can set just about anything you like.
Comment: Technically speaking only custom components in a VF template can use controllers - the template itself can't have a controller.
Answer: This is a bit crufty, but could work:

Add a custom field on Contact called something like Custom_Email_Note__c
In your code, set c.Custom_Email_Note__c = 'Your custom message'; and Update c;
Send the email using the code in your question (which could now pull that string from Contact)
Clear the field (c.Custom_Email_Note__c = '';) and update again.
Answer: I know it's a old post - but if anyone looks for an answer to populate dynamically computed data, please check my blog post titled 'Dynamically populating custom HTML email template content in force.com with custom dynamic data using Apex' on how to accomplish this.


Where can I learned about important warrior macros?

Question: As mentioned in the previous posts I have recently rolled a dps arms warrior.  I am interested in both dungeons and pvp.  What site is a good starting point for learning important warrior macros?
Comment: This is sadly a question asking for a list, which does not work will with the question/answer format of this site. You're probably better off asking on some kind of forum.
Answer: WoWWiki and Wowpedia keep documented lists of "useful macros". Beyond that, WoW Macros has sections for macros based on classes (such as their warrior section) and World of Warcraft Macros Database does the same thing. Some of these macros can be a bit dated, but generally-speaking you can find some useful stuff.


How to change product list grid and image size?

Question: How to change product list grid image size and how to change grid from 4 to 3? Because the images are so small now.
I want to have larger images and change grid from 4 to 3.
I am using Magento 1.9.1.
Answer: To change grid 4 to 3
Copy file app/design/frontend/rwd/default/layout/catalog.xml into your theme
and change below code
<action method="setColumnCount"><count>4</count></action>

to
<action method="setColumnCount"><count>3</count></action>

in layout handles catalog_category_layered and catalog_category_default

To increase image size in grid view
Copy file app/design/frontend/rwd/default/template/catalog/product/list.phtml into your theme
and inside grid mode code, change below code
<?php $_imgSize = 210; ?>
to
<?php $_imgSize = 250; // your required image size ?>

Answer: There is a lot of information about this if you search in google (also in stackexchange too). For example please see these:
http://www.templatemonster.com/help/magento-how-to-change-products-images-dimensions.html
http://www.templatemonster.com/help/magento-how-to-set-number-of-columns-in-category-listing.html
Answer: I have an alternate approach to address this issue.
If you are using a template that load jQuery, you can use the following code and place it in: System > Configuration > General > Design > HTML Head > Miscellaneous Scripts

Your image tags shall have width and height attributes assigned as defined in the code. Ideally, this code should not mess-up with responsiveness as i have successfully used this code on my site.
This jQuery approach is used just to avoid changing php template files as any subsequent upgrades to magento can break some parts in future unless you keep full track of changes to these template files. That's why i prefer jQuery technique.
Do let me know your thoughts if someone find the jQuery approach not appropriate.


How do electrons carry energy

Question: So when electrons leave the negative side of the battery and the voltage get lost across the resistors in the circuit ..how do the electrons lose their energy ? How do the electrons carry that energy that produces the electricity then they LOSE it in the resistor ?
Comment: This question must hold some sort of a record for a large number of answers all with zero votes after several hours. This is not to say it's a bad question, but perhaps it cannot be answered.
Comment: @Neil_UK : added a seventh!
Comment: Electron scattering is what you are looking for.
Answer: 'How' is a question that's impossible to answer.
You have to start with the observation that when you connect a battery to a resistor, energy is transferred.
Now there are several levels of model we can invoke to summarise how much is transferred. We can also push those models to 'explain' what's going on in other terms that we feel good about, that we think we understand.
The simplest model is circuit theory. The battery delivers a current, from a voltage, and the product is power. It doesn't tell us what voltage is, or current consists of, but it's neat for doing calculations ranging from the very simple to the very complicated. The hydraulic analogy is often invoked to make it more familiar.
Next we could think about mobile electrons. Voltage is a measure of how much energy per unit charge is involved when they move. It doesn't tell us what electrons are, or how energy is transferred. There are a lot of electrons in the conductor, some move, most don't, why the difference? They gain energy by moving 'down' the field from the battery. How does that get transferred to the resistor? Is there friction between the electrons and the atoms in the resistor? Do they hit the atoms? Do they get scattered? All three are defensible explanations, depending on the level of model, and what you want to assume.
At the lowest level of our understanding is quantum mechanics, where electrical effects are mediated by photons (yes, even at DC). Frankly, that does my head in, because I lack the imagination and skill to work with those models. But it underpins the simpler models, and it still doesn't tell you what's 'really' going on.
Just get used to the idea that energy transfer happens, and learn enough equations at the simplest possible level of model to allow you to figure out how much.
Answer: The electrons do not "lose energy". The energy is transferred via the electric field, which can be viewed at the "pushing force". Crudely (an inaccurate analogy) the field pushes the electrons through a resistance and this causes friction through collisions with the atoms.
Answer: Start by observing what happens to an electron released into a vacuum with an electric field across it, say produced by a 12V battery. It accelerates across the electric field, picking up kinetic energy - 12 electron-volts to be specific.
The electric field provides a kind of potential energy, just like gravity does to a Fig Newton or an apple, providing the acceleration. This is why a voltage is called a potential difference, and the field is called a potential gradient. And the acceleration translates potential into kinetic energy.
It doesn't matter whether the vacuum is 1 metre long, with 12V/metre electric field, or 1mm long, with 12000V/metre, the final energy is 12eV. (And you can work out the final velocity using basic Newtonian physics, if you know the mass of an electron (9.1*10^-31kg) and the value of 1 eV in Joules - from the definition of a volt, this is the same as the electron's charge in Coulombs, 1.602*10^-19). The stronger electric field across 1mm implies more acceleration but a shorter journey, which cancel out to the same final velocity.
Now introduce a thousand obstacles - the atoms in a very small resistor. The electric field is the same, so the acceleration is the same, but after 1/1000 of the distance, the electron bumps into an obstacle, losing kinetic energy and momentum, and has to start accelerating again.
That lost kinetic energy is transferred to the obstacle, vibrating it - heating the resistor.
Answer: It is easiest to demonstrate the process with water flow analogy.
Imagine that the battery is a water tower filled with water and water droplets represent electrons. Water pressure at the bottom represents voltage and water flow represents current. Ground represents positive terminal, the one where water (electrons ) will flow when allowed. In this system water it self does not have any energy, it is because it is held up high it can do some work when falling down.
Same with electrons: battery is just a chemical device that collects and stores some electrons at the negative terminal. If a load is connected between negative and positive terminal, electrons will start to flow through it and heat it in the process - do work. Same way water held up high can do work (and does in hydroelectric plants) when falling down. Energy is stored in the system, not water or electrons themselves.
Hope this helps.
Answer: Energy cannot be stored in conductors unless they are long or coiled into inductors. The Energy is E=1/2LI^2
Conductive Atoms stay in tact and their electrons never lose energy, but the energy to excite them can be lost.    The flow of electrons is very slow (drift velocity) but the waves of collisions is fast (c, speed of light) dependent on the surrounding insulation which slows down the speed of light inside
 the (dielectric e, which creates a capacitance, C).
The atoms themselves are lossless. (Conservation of Energy)
But the atoms on conductors have electrons that are easily excited (lol) and escape orbit and jump to the nearest atom with a spare space in their shell in the outer orbit.
The conductor property also has resistance which is the effect of  the collisions that can dissipate heat in the exchange from bouncing around with a flow of charges i.e. I^2R=Pd losses. (Ohm's Law)

Electrical Energy is only stored in reactive elements, L or C where Pc = 1/2CV^2 but is generated by moving coils or magnets or batteries and lost with anything that has resistance with current flowing thru it.
Batteries are chemical electrolytics like e-caps , except roughly 1000x (1k) higher capacitance per unit volume with a chemical makeup to have a galvanic cell reaction voltage.
All insulators are dielectrics, even a perfect vacuum. The dielectrics can store charges and will have some contaminants or  particles that can transfer charges that lead to breakdown voltage... even if it is a really small fraction like a 100 particles per zillion (lol) in a high vacuum chamber <4 torr. At this point the breakdown voltage /mm rises has risen sharply. (Paschen's Law)
Comment: In inductors energy is stored in a magnetic field, not conductor it self. Same way it is stored in an electric field in a capacitor.
Comment: Yes we ought to say that, but we measure it by I and V, since you cannot have one without the other. ( H fields and charge flow & E field and charges ) That's what reactive parts (L&C) do is create the fields which in turn create magnetic or electric forces which in turn stores power and over time stores energy in the interval standardized by 1 second. in Joules or watt-seconds.  So it becomes synonymous or equivalent energy depending on choice of units.
Comment: **But you are correct*, the Magnetic field is outside the conductor and Electric field in caps is between the conductors. and you cannot store the energy without both zones, the conductors and the fields around them or between them respectively.
Comment: I had no intention to nitpick. It is just that the first simplifier statement does not fit your further detailed explanation. It does fit the question's level though. While rest of the answer seems to be overcomplicated and steers to broader context a bit. But I'm new here, let me know if my comment is inaccurate.
Comment: your perception is good. I tend, to make my answers suit a broader audience and sometimes too much detail, and push some to learn more at the expense of confusing some.  It was a hasty reply , so oh well WYSIWYG.
Comment: feel free to make suggestions to improve it.  Sometimes the score is about the simplest answer which is not best for me, but maybe a newbie.
Answer: Its called a voltage, the battery has zillions of ions that want to move an electrode to combine with electrons. All of the ions combined create an electrical potential called a voltage across the terminals of the battery. That makes the electrons on one side of the battery want to 'flow' to the other.
If you put a resistor in series with the battery, it gives them a pathway to flow to the other side of the battery. As they travel through the resistor they bump into other atoms and lose their electrical potential and create heat.

How do electrons carry energy


What's the difference between L1 and L2 networks?

Question: I know there are some networks like polygon. I would like to understand the difference between L1 and L2 and if I have ether in one network can it be transferred to others?
Answer: Layer 1 is the orginial layer of the blockchain like Eth
And layer 2 is built on layer 1, like polygon.
Kind regards,
Max
Answer:
between L1 and L2 and if I have ether in one network can it be transferred to others?

L2 chain cannot exist without L1: essentially it relies on the L1 chain for its chain security. In theory, you should always be able to withdraw back from L2 chain to its original L1 chain, even though the L2 chain would fail somehow. However, if L1 fails then all L2 chains on the top fail as well.
L2s trade-off cost and speed for complexity: Doing transactions on L2 writes less data to its parent chain L1, as doing transactions directly on L1, using compressed proofs or checkpoints or similar.
Example of L2s: Arbitrum on Ethereum, Optimism on Ethereum.
Example of not L2s: Polygon, BNB Smart chain, Avalanche. These are independent. Even if Ethereum fails Polygon will keep running.


Can commas be left out?

Question: In the following sentence, can  commas be left out?

Latin, still taught in many parts of the world, is a dead language.
Answer: I would not remove the commas in that sentence as it stands. It would become a run on sentence by combining too many verbs.
I'd reform the sentence rather than just dropping the commas. Something like "Latin is a dead language but is still taught in many schools."
Commas should be thought of as breaks in speech. If you read your sentence aloud, only stopping for punctuation, then you can get a better sense of where you should be putting periods and commas.
Answer: You shouldn't leave out the commas. It would make the sentence harder to understand. The phrase "still taught ..." is an addition. You should separate it from the rest of of the sentence. Instead of using commas you could choose to use brackets () or dashes — —.
In speech you would use intonation to separate the phrase.
Answer: Commas are not there to decorate, or to confound you - they are there to help the reader both to read the sentence easily, with pauses in the places that you intend - and also, they help to divide up logical clauses or 'chunks of meaning' in the sentence - again, so that your words may be easily understood.
Imagine reading the following in a monotone - with no pauses:

Latin still taught in many parts of the world is a dead language.

Try reading it aloud now. How does it sound?
Isn't it hard to understand? Don't you wonder "what is 'Latin still taught'?"
How easy is it to discern the relative clauses? What are the clauses?
Is: 'parts of the world is a dead language' a clause?
Is: 'Latin still taught in many parts of the world' a clause?
Think about - where you want the pauses to be - and - what separates the clauses?
What you already have is perfectly clear:
Latin (pause)
still taught in many parts of the world (pause)
is a dead language. (stop)
So:
"Latin, still taught in many parts of the world, is a dead language."
...is easy to read, it's easy to hear the clauses - and thus, also easy to get the meaning.
You don't have to pay for the commas you use, and they are not going to run out - so why not use as many as you want and need?
I would leave it as is.

Can commas be left out?


ICEFaces page refresh

Question: I have a page where a user enters data and hits a "save" button.
The data gets saved to the db, and I want the page to refrsh itself to reflect the new data in the db.
I am using a managed bean, how do i get the page to refresh on its own?
Answer: There are two options which come to my mind:

Make use of JSF navigation rules
Use the rendered attributes

ad 1)
Define a page to which you'll navigate to after hitting "save".
For doing that, your action for actually saving the data to DB will go into the method defined as an actionListener or, if you want to make your next page depending on the outcome of the saving process, as action.
Navigation rules will be defined in faces-config.xml
If no navigation rule matches a given action, the current page will be redisplayed (although from the experience i made this refresh is different to a common HTML refresh).
ad 2)
If you've some lists or a data table on the same page set to a model in your bean, changes will automatically be displayed except you're using the immediate keyword set to true on your save button.
Additionally you might consider a panel with a content of your choice which has the rendered property set to a boolean in your bean, which will be triggered within the saving process and therefore let the content be displayed only after hitting save.
Answer: You can make use of the AJAX push feature of IceFaces. This initializes a re-render of the client.
The recommended (and easiest) way is to use the SessionRender API in your managed bean:
SessionRenderer.addCurrentSession("myGroup");
SessionRenderer.render("myGroup");

Consult the Icefaces developers guide for more information.
Answer: It depends on how you do it.
When you click the button, the JSF life-cycle is kicked off, if you kick off the save to the database within the button's action, whatever values you update in your manage bean should be reflected in the page automagically.  The JSF lifecycle does this for you automatically and icefaces can do it using the AJAX bridge so you won't be required to do a page reload.
If you're doing work asynchronously, you'll need to use the Push API icefaces provides you.  To kick off the life-cycle from the server end.

ICEFaces page refresh


Chinese citizen with Green Card transit in Incheon airport flying from Beijing to Seattle - do I need a visa?

Question: I'm flying back from Beijing to Seattle with layover at Incheon Airport for 6 hours. No plan to get out of the airport. Do I need to have a visa for the transit? The first leg is operated by Air China and the second one by Asiana Airlines. They were issued by the travel agent as one route ticket. Thanks in advance!
Answer: According to the IATA Travel Centre, it looks like you are ok to travel through ICN without a visa. See below and the link for more info.


Matlab Matrix multiplication element wise from different sized matrices

Question: I am optimizing a MatLab script by using vector multiplication instead of for loops. There, I got a problem with the vector selection.
In my calculation I got two matrices, M1(x,x,x,x) and M2(x,x). When I try to vectorize those matrices and multiplicate them elementwise, I get an error. Their sizes mismatch.
product = M1(1,1,:,1) .* M2(:,1)

size(M1(1,1,:,1) -> 1 1 6
size(M2(:,1)) -> 6 1

If I use the command squeeze on M1 it is working.
product = squeeze(M1(1,1,:,1)) .* M2(:,1)

The problem is, squeeze takes extremely much time (1/5 of the complete time -> ~50s). How can I still use my matrices without using squeeze? Anyone got an Idea?
Thanks for your help!
Comment: Are you using them in a loop? Show more of the relevant code?
Answer: shiftdim is usually faster, so try
product = shiftdim(M1(1,1,:,1),2) .* M2(:,1)


Security devices other than firewall and IDS

Question: I was just studying about firewalls and IDS/IPS and had a doubt. Are these the only two major security devices that a company invests in? or are there other equipment and security controls?
Comment: What research have you done?
Comment: @schroeder i know that antivirus software should be installed in every computer to protect from viruses, and that programs should be updated regularly to safeguard the network. Also that it is always recommended to install both IPS (Host based and network based) . Furthermore Bastion hosts and DMZ can be implemented in the network topology (although this again relates to the firewall). Also VPN and leaked line could be used to connect branches
I searched through google and security stack exchange for other devices but could find any, most of it only focus on firewall and IPS.
Comment: You don't solve security by gadgets. Read the classics: https://www.schneier.com/essays/archives/2000/04/the_process_of_secur.html
Answer: There are few other choices.  If software is inherently insecure, all you can do is to replace it with something that isn't; or wrap it up in a condom of some sort.  Host-based systems require programs to be invasively, and cooperatively, installed on every client (virus scanners, local network stack IPS).  Network-based systems don't require cooperation from the clients, and try to fix security by parsing traffic.  Some network-based systems require a little bit of cooperation by blocking encrypted traffic for connections that don't submit to scrutiny; and accept the company/ISP's certificate authority (so that the authority at the local boundary can inspect the traffic).
Comment: thanks, i take it that apart from the firewall and IPS/IDS very little other equipment are as effective.
Comment: Read about LANGSEC.  The only real solution is software that has strong protocol specifications, and strong guarantees that it behaves as specified.  In the real world however, organizations have little say in the quality of the software they use.  So everything gets proxied in some fashion; whether it's at the network level (NIDS), or in the network stack (HIDS) or other system calls (virus detect).  I work at a firewall company after being bought from an IDS company.  These things help as much as possible, given the hideous state of the software we all use.
Answer: Proxy, Adaptable Security Appliance, DMZ, and Automated Vulnerability Scanners are some items you'll find in the wild that are hardware. There's plenty more security related software items that will help you with research such as Splunk which takes logs and makes them searchable.
Comment: I definitely second this.  Vulnerability maps give a todo list of what need to be secured, and tells you where to look for trouble.  Mining the logs ensures that you don't overlook trouble when it actually happens.
Comment: @GingerBeard well thanks ill check it out, thanks Rob too


What is the difference between Spatial autocorrelation and autocorrelation

Question: Am working on classification of some diseases and i have successfully applies the spatial autocorrelation. But i reall want know the distinct difference between Spatial autocorrelation and autocorrelation.
Answer: Usually, autocorrelation is used to measure correlation between variables which measure "the same thing", but at different points in time.
Spatial autocorrelation is the same, only that it measures correlation between variables measuring "the same thing", but observed at different spatial locations, such as geographical coordinates.  Since space is multidimensional (usually 2 or 3) while time is onedimensional, spatial autocorrelation in practice have a rather different flavour from autocorrelation in time.


DC motor disconnect sensor

Question: Looking for advice on how to turn off a motor when there is an item blocking a sensor. I found an inductive proximity sensor that I think could work. I am trying to make a brass case annealer similar to this one
Comment: It's called a "relay."  You simply need your sensor to provide sufficient voltage or current change to trigger a switch.  What kind of switch depends on the voltage & current your motor draws, how many actuation cycles are expected in the system lifetime, etc.
Answer: What you are looking for is a normally closed relay which is sometimes abbreviated as NC relay. You should place the relay in you circuit so that switch side has the ability to interrupt the motor when the sensor is tripped. Here is a possible schematic of how your circuit could work.

When an object is placed in front of the sensor it closes the sensor which opens the relay which cuts power to the motor. This is one way to achieve control of your motor when an object is placed in front of the sensor.

DC motor disconnect sensor


Matching two audio inputs (signals)

Question: this is for an application in which passwords are stored in the form of audio inputs .
In order to provide user access , the password(in audio form) will be matched with already stored password(audio only) in the database . I wanted to know how to measure the extent of similarity in two audio patterns . the audio patterns can be a clap sequence , knock sequence , whistle etc
Answer: Look up acoustic fingerprint or audio fingerprinting and dynamic-time warping for some basic technologies used to compare audio files.
Answer: You could also take a look at pattern recognition in the time-frequency domain. This would imply to take the entire audio signal and perform time-frequency analysis (finding a pro version of the spectrogram) and analize that as an image. If the two time-frequency representations match for the audio files, it is very likely that they are the same password.

Matching two audio inputs (signals)


Collecting data from GSM devices

Question: this is my first question on electronics, so I hope I will get it right. :)
GSM and GPS are topics which are quite new to me, but I will try to be as clear as I can.
Is it possible to collect data about all the present GSM devices in the room or on a floor, with my device, and then calculate via GPS the distance between my GSM device and all the others? Can it be done via GPS or should it be done via GSM module? Can that kind of collecting be done, at all?
Thanks in advance!
Answer: You can use GPS to calculate the position of your own device if you happen to have a good enough sky view to receive the GPS signal.  Otherwise, GPS is not useful.  GPS is the Global Positioning System.  A GPS receiver uses signals transmitted by GPS satellites to determine it's location.  However, the GPS signals are very weak and cannot penetrate effectively through buildings so GPS is of little use indoors.  Also, a GPS receiver can only determine the location of it's antenna.  It cannot be used to determine the location of another device.
As for tracking GSM devices, the best you will be able to do is radio direction finding, and then only when the units are transmitting.  It may be possible to extract some information about the GSM devices, but it will require a highly specialized receiver.  A software defined radio unit would probably be the most economical route.  Also, you would likely have to break GSM's encryption if you want to gather any information about these devices.  This is likely illegal.  Another possibility is to build your own base station and set it up so that the phones connect to you.  However, this is far more complicated and even more illegal because you would have to transmit on licensed frequencies.
Comment: I wonder if GSM triangulation through picocell / femtocell type repeaters would be an option: Those devices exist and are legal in many jurisdictions.
Comment: Thanks @alex. I didn9t want to collect any information about the devices, but only to see how many cell phones are around me and their distance from my cell phone. I was guessing that they have to transmit constantly, since the base station has to locate them somehow. Or not? That is what I wanted to catch, just their signal.
Comment: I'm actually not sure about what the GSM base station handshake consists of.  You will definitely be able to easily detect them if someone decides to make a call or browse the web, but I am not sure about when they're just sitting idle.  I do not think the base station keeps a continuous lock on a phone unless the phone is actually communicating data with the tower, so it may be difficult to detect an idle phone.
Answer: They transmit very intermittently on high power (you can occasionally hear "bipping" on cheap computer speakers when SMSing, see Why does GSM cause speakers to buzz?). If you fill a building with 900MHz recievers you could probably do time-of-flight direction finding, but it would be neither cheap nor easy.
GPS is recieve-only. So you'd need the cooperation of the phones via an app or similar.
Comment: Thanks. I know I need the phones cooperation, but I thought there was an easier way to do it. (The easier being cheaper :) ). I wanted to do it solely by making an app that would scan the room, and find their "signatures" or something....

Collecting data from GSM devices


Resources for multivariate normal distribution

Question: Is there any particular book/online notes that I can use to better understand the multivariate normal distribution? I could also do with a bunch of questions and solutions.
Answer: There is the book
Tong, Y. L. (1990). The multivariate normal distribution.(Springer)
I also consider useful the paper
Hamedani, G. G. (1992). Bivariate and multivariate normal characterizations: a brief survey. Communications in Statistics-Theory and Methods, 21(9), 2665-2688.


I can't make bootable USB on 2008 iMac 2008 running El Capitan

Question: I have 2008 iMac and OS X El Capitan on it. I will make bootable USB drive for my friend, but I can't. I format my USB as Mac Os Extended and GUID parition map, then I downloaded InstallMacOSX.dmg file from apple; double click on it and I have installmacosx.pkg. (I can't find The El Capitan installer to the /Applications folder). I click on this package and I have an ALERT: "OS X v10.11.6 is already installed on this computer. Use the Updates page to install the 10.11 update or if you would like to download the full OS X installer click Continue". I click continue and have to select destination disk, but when I select my external USB drive, I have the message: "OS X can't be installed on this disk. macOS isn't installed". Can you help me?
Comment: Welcome to Ask Different. Have you tried this guide https://support.apple.com/HT201372?
Comment: There are several different ways to create bootable drive from installmacosx.pkg, you can try to use the steps described in here: https://apple.stackexchange.com/questions/379603/how-do-i-create-el-capitan-installer-on-a-catalina-or-post-el-capitan-installe
Answer: OS X El Capitan has a recovery partition which is used to reinstall OS X on your Mac should you need it. Instead of using the .pkg, You can try copying the entire contents of your recovery partition to your USB. After formatting the USB as macOS Extended, go to OS X Recovery by pressing Command + R. Then, unmount all volumes except the Recovery partition and USB and go to Terminal. Then type
cp / /Volumes/USBNAME.
If you are trying to make a ready installation of OS X El Capitan, then you can use your recovery partition to reinstall OS X to a USB drive. Simply boot into OS X Recovery and select the reinstall OS X option. Select your USB drive and connect to WiFi if prompted. If you would like to install macOS Catalina on the USB, then Apple says you must upgrade your computer to macOS High Sierra to avoid issues with the firmware and in order to have access to the Install macOS Catalina application.


Product quantity -1 and backorders

Question: Backorders are disabled in system > configuration > catalog > inventory but a customer bought a product with quantity 0, so after he purchased it, product's quantity became -1.
How is it possible?
I want that the customers can't buy a product with quantity 0.
Answer: You need to check below setting
In particular product setting -> Inventory -> Backorders set to "No Backorders".
System-> Configuration -> Catalog -> Inventory -> Product Stock Options -> Qty for Item's Status to Become Out of Stock set to "0".
Refer below Inventory settings.

May be helpful to you.

Product quantity -1 and backorders


The argument 'sql' cannot be null, empty or contain only white space. When first create the database

Question: I'm using entity framework to process the sqlite database. If there's no database and I want to insert one record, it will create the database successfully (I found the database file in disk) but throw the error:

The argument 'sql' cannot be null, empty or contain only white space.".

Then next time running, because the database has been created, all code works well with no error.
DbContext.Database.ExecuteSqlCommand(sqlCmd, parameters.ToArray());

Only throw above error when Database not exist. If exist, work well.
Comment: It would be awesome if you could provide a [mcve]
Answer: This error may occur in case the "sqlCmd" variable is null or empty when the ExecuteSqlCommand method is called. Please make sure that this variable is correctly initialized in case the database does not exist.
Comment: The "sqlCmd" does have value. I can find it through debug. Obviously entityframework does some other "process" when the database does not exist.


Can my cabinet lights be operated with a dimmable switch?

Question: The previous homeowner underwent a kitchen remodel and cabinet lighting was installed. I did a "Google" search for what I think is the model number listed on the back side of the unit but came up short - see picture. The manufacturer is Nasun and I believe the model number is WFL701A3W
Answer: According to the instructions, yes, they are "suitable for switch dimmer for dimming function".
No promises as to how well they will actually work with any particular dimmer.
Answer: I have a light where I finally placed LED light bulbs (I was tired of replacing the other bulbs every 6 months or less).  That light has a dimmer switch and with the LED it doesn't work. However, you have both: LED that support dimming and LED that do not support dimming. To be noted: I have both kinds on that system (it supports 5 bulbs) and because two do not dim, the whole thing doesn't dim.
However, has @nobody mentioned above, the instructions say it supports that feature so it is likely LED that will work. However, when you replace those LED, you'll have to make sure you purchase the type that supports the dimming otherwise you're likely to have to turn the power to the max. so it works.


Coderush and resharper, do they work together?

Question: anyone have any experience of using them together?  How well does it work? or is it just too much grief?
Answer: I use both tools succesfully. Yes, both wants the keyboard, but they want it in different manner. You can configure them to work together without too much problems. All is about configuration and the learning curve.
Main issues I've faced are: managing parentheses and brackets (just choose which one is going to do this), templates (not a real problem: use tab for one and space for the other), suggestions (configure different keys for each tool).
CodeRush plugins and Resharper plugins works well together and the result is a true delight. There are no conflicts between the tools. Just take two weeks to use it with easy.
Answer: I've used Resharper for awhile and recently installed the free Coderush Express too.  After a week or so, I can say that Coderush has not gotten in my way in the slightest, nor has there been contention between the two tools.  Admittedly, I'm way more familiar with Resharper and wouldn't know if half of Coderush was not functioning, but I'm pleased with this set-up currently.
Update: the tab key to go to other usages in CodeRush sometimes interferes when trying to complete a type in a template.  For instance, typing foreach creates a foreach template.  If while editing the template fields, tab is hit, say, to complete the entry, CodeRush zips you to some other place.  Thankfully Esc recovers from this.
See the comments for advice on remapping keys.
Comment: I'm doing this as well.  There are some conflicts, but you can remap the key bindings for coderush using Ctrl+Shift+Alt+O.
Answer: You don't want to do that.  Both ReSharper and CodeRush want the keyboard.  Specifically, CodeRush remaps the escape key (ESC) for its own purposes.  ReSharper does not like that (note: ReSharper doens't do anything special with the escape key, but it still doesn't like it).
As for choosing between them...they both have their points.  CodeRush has better templating and more refactorings.  ReSharper has built in unit testing for NUnit, and a healthy set of plugings.  ReSharper also has Templates, and a slew of Keyboard short-cuts.
Comment: I vote Resharper. Once you get used to it, you'll never code without it.
Answer: I was greedy enough to do that. It took my VS2008 ages to startup. Everything slowed down.  I have 1 Gig of ram. Not sure if that was the case. I removed coderush because I was more used to the resharper keyboard layout.
Comment: I think I would have taken the money you spent on CodeRush and Resharper and bought more memory.  :)
Comment: yeah I know no one says "Dude, you got 1 gig RAM!!!!" but they say "You just got 1 GIG RAM???psst.."
Comment: 1Gig is a bit small these days I'm afraid.
Answer: It's not a problem at all to use Resharper with CodeRush. I worked in such style some time. But why?
IMHO CodeRush in couple with Refactorpro are much better in performance and usability then resharper. Also resharper reduces performance. Almost all features expect probably nunit integration are the same, try to find them in resharper or in codeRush and use only one of them. I prefer coderush
Answer: There is a related question. In one of the answers to that question an article was suggested that seems to be useful:

Jim Holmes has an awesome blog post that goes through how to make
  these two products work in the same install.
http://frazzleddad.blogspot.com/2010/01/making-devexpress-resharper-play-nicely.html
I don't even want to think about how many hours and install
  permutations it took to come up with this sequence.

I did not try it.


Is Shanks that strong?

Question: After the War of the Best, when Whitebeard died and there was no hope for the pirate side, Shanks enters the area and everything ends on his command. So I'm wondering if Shanks is really that strong (that three admirals together couldn't defeat him) or do they just honor the saga of Whitebeard?
Comment: Magma is hotter than Fire, and sword is hotter than magma. .. logic of One Piece. he he he.
Comment: @user1466 shanks' haki coated sword is the hottest in the OP universe!
Answer: Shanks is very strong, though that isn't the only reason why the navy stopped. Being one of the four yonko means that his crew is one of the most dangerous in all of the Grand Line. Of course, Whitebeard was at least as strong, if not stronger, but Shanks is no weakling either. He has been able to hold his own against a number of powerful opponents, including at different times and in different situations, Mihawk, Kaido, and Whitebeard. The Marines only came prepared for one Yonko at a time. Facing both the Whitebeard pirates and the Redhair pirates would have been a lot more than they could chew.
Shanks is also not a terribly dangerous pirate in the eyes of the world government, though he is very powerful. They view him as a threat, but acknowledge that he probably wouldn't be the one to start a major conflict on his own. He is respected by a number of people in the navy, including Sengoku, who would rather avoid a conflict with the Red-hair pirates. The navy probably would have been able to win against the Red-hair pirates at that point, but they would have sustained heavy losses in the process which were simply not worth it. He is also rather charismatic, so that probably helped.
Ultimately, Sengoku decided to end the battle out of respect for Shanks, not necessarily because they could not have beaten him, but he is definitely still one of the most powerful people in the world.
Source: One Piece Wiki
Comment: it was ben beckman who pointed the gun at kizaru not yassop
Comment: Don't forget that some of his crew cornered the Admirals, such as Ussops dad Yassop pointing his gun at Admiral Kizaru
Answer: Since Shanks bounty is unknown, and we haven't seen any serious  fights that actually went down, we can only estimate  Shanks power from his brief appearances, and the dialogues about him:

He lost his arm to a Sea King in an attempt to save Luffy, then uses Conquerors Kaki(Haoshoku Haki) to scare it off.
He uses Conquerors Haki to knock out most of Whitebeard's crew, then briefly clashes blades with Whitebeard, the strongest man in the world.
He stops Akainu with his sword and saved Koby.
When he had two arms, he was in contention with Mihawk as the strongest swordsman in the world. Whitebeard himself said that he still remembers the fights between Mihawk and Shanks, and they echoed all around the Grand Line.
However, Mihawk is no longer interested in fighting him.
In Chapter 907, he went into Mary Geoise to talk with the five elders.

Based on this information, I would say that Shanks is well deserved of his title as Yonko, but not as powerful as the other three. He could also probably take on a Marine Admiral or even the fleet admiral individually. Given that the Navy suffered massive losses already at the battle, I would say that Shanks, along with his crew, is powerful enough of a threat, to stop the war at that point.
Answer: Yes. He is currently one of the Four Emperors of the New World, meaning that he is one of four most powerful pirate captains in the Grand Line. Not only that, but he clashed with Dracule Mihawk, currently the World's Greatest Swordsman, on a daily basis before he lost his arm. In addition, he was able to single-handedly(See what I did there?) Block a two-handed blow from Whiteberd's bisento with nothing but a single arm. He was also able to block an extremely powerful magma fist from Admiral Akainu (Which was hot enough to burn Whitebeard, renowned as the World's Strongest Man) with nothing but his sword, strength, and mastery over haki. Even before he clashed with Whitebeard, his presence alone started to cause physical damage to Whitebeard's ship and knock out his many men (Seasoned and experienced pirates who were able to survive the harsh journey and adventure of being in the New World), and literally scare off a Sea King with his haki, showing how immensely powerful and experienced he is. So in conclusion; yes, he is that strong.
Comment: Welcome to Anime & Manga! While we all appreciate your contribution, please *refrain* from answering old questions when you have nothing to add or contradict to the alread-existing ones. It's also better to include relevant sources/information in your answer.

Is Shanks that strong?


Mask forwarded blogger urls to own domain urls

Question: Following Rounin's answer  carefully written (thanks a lot) on how to redirect any blogspot urls with any extension to the mydomain.com corresponding URL, now the question is how can I mask the URL?
I mean, once the blogspot URL redirects to the mydomain.com, I want to continue to display the original blogspot URL instead of the mydomain.com.
Comment: I'm not sure I fully understand what your trying to accomplish.  You state "I want to continue to display the original blogspot URL instead of the mydomain.com".  I wonder if you mean that you want to show the original blogspot subdomain and domain in the location bar?  So that content for http://maskedurl.blogspot.com/2013/03/illustrations.html  would show up in the document, but window location would show as http://maskedurl.blogspot.com. Either way maybe this helps. http://stackoverflow.com/questions/824349/modify-the-url-without-reloading-the-page/3354511#3354511
Answer: You can use the following JavaScript snippet for that -

And the bare minimal CSS would be -
body {
    overflow:hidden;
}
.maskingFrame, body {
    width:100%;
    height:100%;
    border: none;
}

You can check a demo here (This is the homepage) and here (This is an internal URL from other site which doesn't exist on the original blogspot URL)
Answer: In privous answer you redirected page from blogspot to your domain. This causes the url to be changed. But if you want to show contents from another url without changing url it could be done through using .htaccess file.
the code in htaccess file should be like this:
RewriteCond %{HTTP_HOST} ^DomainA.com
RewriteRule ^(.*) http://DomainB.com/$1 [P]

Here you could find more details and info about .htaccess file.
I don't know if it is possible for you to place that file in your blog or not. If you have not access to place this file into your blog you can place it on your domain host, and redirect from your domain to your blogspot page but if ask me I recommend you redirect and encourage people to your own website rather than keeping them using weblog address. You'll not need weblog if you have your own website.
Comment: how can I access the blogspot htaccess file? where is it? where should I put this code in the blogspot?
Comment: @Mpondomise It's a file which can be placed at any folder of a website. For placing a file you need at least a ftp access. I doubt you have ftp access for a blog. So it could not be possible for you to redirect from blog to domain preserving your blog address. But it's possible if redirect from domain to weblog.


How can I get control of the generation process of config.xml file for a jenkins job?

Question: I'm new to Jenkins and now I'm supposed to develop a jenkins plugin. In the plugin will create a new job type, and generate the configuration page of this job type. I've finish this one by extending the class  "hudson.model.Project" ;
For now, when I click "save", nothing goes into the configuration file(config.xml) of the new job. I want to get control of the configuration file's generation process in order to set default builders and parameters of the certain builder for each job.
Anyone could help in explain how could I make it with Jenkings Plugin (especially by extending hudson.model.Project)? Or anyone can tell me which part of the src code or any documentation I should read in order to get some knowledge of it?
Any help will be appreciated!
Thanks!
Answer: There is already a plugin to create new jenkins jobs programatically  https://wiki.jenkins-ci.org/display/JENKINS/Job+DSL+Plugin


Which IBM composer gate realizes the 2x2 single-qubit $-I$ matrix?

Question: Which IBM Quantum composer gate is used to realize the 2x2 matrix $-I$ acting on a single qubit? And how is it called?
Comment: If I understand your question correctly the matrix you give is only a (-1) global phase factor away from the identity matrix
Comment: Yes, thats true, so is there a gate for that in IBM composer ?
Answer: The 2x2 matrix $-I$ represents a gate that performs an identity transformation and applies a global phase $e^{i\pi} = -1$ on a single-qubit state. In the IBM Quantum composer you can use any single-qubit rotation gate with an angle $\theta = 2\pi$ to implement such operation. For example, let's consider the $RX(\theta)$ gate:
$$
RX(2\pi) =
\begin{bmatrix}
\cos{\left(\frac{2\pi}{2}\right)} & -i\sin{\left(\frac{2\pi}{2}\right)} \\
-i\sin{\left(\frac{2\pi}{2}\right)} & \cos{\left(\frac{2\pi}{2}\right)}
\end{bmatrix}
=
\begin{bmatrix}
-1 & 0 \\
0 & -1
\end{bmatrix}
$$
Answer: Upto my knowledge there is no such special gate  in IBM composer to represent the gate
\begin{bmatrix}
-1 & 0 \\
0 & -1
\end{bmatrix}
which can also be represented as ($e^{iπ}$)$I$
where $I$ is the identity gate and $e^{iπ}$ is a global phase.
There is no special gate to perform this operation but you can use $Z$ gate which is a phase gate to perform this operation however it works when qubit is in state $\left| 1 \right>$.


With a UK visa from Ghana, do I need another visa to leave the Netherlands to the UK?

Question: I am a Ghanaian going to the Netherlands and onwards to the UK. Do Ineed a visa to enable me to continue my journey?
Answer: No you don't. If you have a visa for U.K. you can go there from anywhere as long as you have all the applicable transit visas.
Answer: You should have no problem leaving the Netherlands going to the UK if you already hold a UK visa.
There is no separate document needed to exit the Netherlands.
You could still be refused entry to the UK if there was a problem with the visa such as a significant change in your circumstances after the visa was issued. This is uncommon though


ESP8266 - IoT - Light Switch / Triac vs Relay

Question: All of the IoT switches (AC) I´ve seen so far are relay based and I´ve been doing some custom ones for my home.  For small loads circuits (lightbulbs max 100W,  110VAC) would it be safe to use a triac instead of a relay enclosed in a light switch box?
I´d like to have four circuits with a total of no more than 500W, 110VAC and in this case the size of 4 relays would make it difficult to fit. I was planing on going with triacs / opctocoupler making the front plate of the control made of aluminum and place all triac there to use it as heat dissipation element...
I´ve seen some dimmers going on this route but I´ve never seen an IoT switch using it - is it only related to cost?  Any advices on this? No need for schematics or details just advices related to the risks this kind of usage.
I know there are lots of items related to relays vs triacs in general but I´d like some advices here lated to enclose it on a switch box.
Comment: Does this answer your question? [Triac versus Relay](https://electronics.stackexchange.com/questions/3352/triac-versus-relay)
Answer: Triac should work just fine, you need to take care of the heat dissipation though.
The reason is probably related to cost / simplicity, although a Triac (properly designed) will be more reliant over time than a relay.
Answer: Triac vs relay: You need to consider these parameters to take a call:

Cost
Space requirements
Thermals
Switching cycles
Contact sticking
Immunity to line noise/spikes

Relays are metal contacts that get activated when you pass a current through its coil. This gives a very low resistance path and is suitable for higher currents. Advantage primarily comes from the fact that you do not need a lot of cooling components. A compact relay can easily handle 10-15 amps without heating up a lot. Depending on the exact application, the benefits of using a relay are low cost, smaller size, better thermals, and immunity to line noise.
With relays, the major issues are limited operation cycles and contact sticking if you are driving capacitive loads.
Triacs can be used without heat sinks or active cooling for low currents (<0.5 amp). They will have a typical voltage drop of 1 volt across them. This means a larger heat dissipation as your current draw increases. You can do away with passive cooling for higher currents as well but the heat sink size will increase for higher currents. Triacs also allow you to do phase control for dimming certain loads (typically used for motor speed control, incandescent bulb dimming, compatible LED dimming etc). You have practically unlimited switching cycles with a triac and there is no concern of contact sticking. However one problem might be line noise that can false trigger your triac. This can be avoided if you use the right spec triac or snubber to absorb those spikes.
There is no general rule that one solution will be compact or the other. Same thing applies to cost and reliability.
Solution selection is quite subjective and depends on the application.
High current resistive load where dimming is not required - use a relay
Low current loads where dimming is required - use a triac
Low continuous current with high inrush current (capacitive load) - use a triac
Very high switching count required (over 100,000 during lifetime) - use a triac


How to find top friends on facebook

Question: I am trying to develop an application on facebook for which i need those friends with whom the user interacts the most on facebook .In short i need a list of top friends of a user. How can i do that.What parameters do i need to look for in the graph api for finding the top friends.
Answer: Facebook doesn't provide this information directly per se but it would be pretty easy to use FQL statements to generate this information yourself.  Check out the FQL documentation asn you could run queries against the stream table to find user interactions.   You could also look at checkin table and album/photo/photo_tag, although these would require more permissions from the user.

How to find top friends on facebook


Dynamically resize VisualForce section in page layout

Question: We have a page layout for a custom object and want to put a Visualforce page as a section in it. However, the height of the content varies, and when I drop the section in, there is a large white space if the content does not fill. How do I deal with this (the part with the big red 'X' through it)?
Answer: Yes it is possible. See the Update - Success at the bottom:
Old Answer - close but not so much
Resizing the VF Page within a Page Layout is not possible though there is an option on the Page Layout that allows scrollbars for the embedded content.
Another option is to (1) make the "embedded" Visualforce Page a Visualforce Component, and (2) write a VF Page similar to:
<apex:page standardController="Your_Object__c">
    <apex:detail subject="{!Your_Object__c.Id}" relatedList="true"/>
    <c:yourComponent recordId="{!Your_Object__c.Id}" />
</apex:page>

Then override the View Standard Button or Link on the Object page with this VF Page.
This option does have some minor downsides in that developers will have to go into the Object from the Setup to change the Page Layout rather than the using the "Edit Layout" link on the top-right.  Also Developers will lose the Dev Tools Menu.  Again, these are minor issues for Developers, but this could add the functionality you are looking for.  It's worth a try.

Update - Success
VF Pages embedded in a Page Layout come over as iframes, so the solution is to write a VF Page using only <apex:detail .../> to bring over the Page Layout and then have JavaScript (via jQuery) resize all the iframes.
Example
<apex:page standardController="Custom_Object__c">
    <apex:detail subject="{!Custom_Object__c.Id}" relatedList="true"/>
    <apex:includeScript value="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"/>

</apex:page>

Comment: Yeah that's a good idea! My only question is: Does this limit my embedded content to only being at the bottom of the page? We need to have it between 2 other sections in the page layout.
Comment: Yes, the content is separate from the Page Layout.  To include embedded in the Page Layout, you are stuck with the fixed Height + Scrollbars
Comment: It might be possible to resize the Embedded VF Page in a Page Layout via JavaScript.
Comment: It is possible.  See the update :)
Comment: Ok so if I understand this correctly, we're still doing the detail page on top and the resized iframe/vfpage on the bottom? still unable to nest it then?
Comment: First nest the "embedded" VF Page in the Page Layout as desired,  and then use the last example I show: use `apex:detail` and the jQuery.
Comment: This is a very nice solution, especially since we can no longer inject JS through the sidebar. I combined this with the HTML5 postMessage() solution and it works perfectly.
Answer: Yes it is possible.
@AmatorVitae's answer will certainly work if you can set up your visualforce page to use apex:details.
If you need more than apex:detail
To resize a visualforce page with a more complex structure, you can do so with some cross domain scripting.
In my answer here, I go into detail about how to accomplish this.
To summarize
You need to

Add a custom link section to your sidebar that executes some javascript stored in a static resource.
Add a static resource that is set up to receive a message from another domain and then use the message's value as the new height of the iframe.
Add some script to your visualforce page that will send a message to the parent domain with the value of the content's height.
Answer: Some more ideas on this include using HTML 5 postMessage() and cross-domain messaging for iframes. I've written up a blog post on how this can be used to not only do dynamic iframe resizing, but also implement basically any collaboration between the parent page and embedded VF that your business requires. HTH
http://salesforcehacks.blogspot.com/2014/12/resizing-embedded-vf.html
Answer: If you are in lightning,  you can use Sfdc.canvas.publisher.resize

Sample code

<apex:page standardController="Case">

Renders Only In Classic

</apex:page>


how to display filed values form People » Account settings » Manage fields

Question: I've added few more fields in "Administration » Configuration » People » Account settings » Manage fields". See the attached screenshots for more details.
Now I want to display user's First name & Last name in page.tpl file. I know that name can be diplayed like this "$user->name". But I want to know how other filed values can be displayed. I want to display the fileds First name, Last name, Phone, Address
Answer: If you want to display first name and last name of the logged in user, then you can follow the below code snippets.
global $user;

$account = user_load($user->uid);

print "First name:" . $account->field_f_name[LANGUAGE_NONE][0]['value'];
print "Last name:" . $account->field_l_name[LANGUAGE_NONE][0]['value'];

The global $user object does not load the fields which are attached to user profile. So, We need to use function user_load() in code.
If you want to display First Name and Last Name of the user profile, then you need get uid of the user from the arguments.
$uid = arg(1);

$account = user_load($uid)

Comment: @SureshAlagar, Its my pleasure.
Answer: The following can be  implemented to get the user details
global $user;
$user_load = user_load($user->uid);
$user_load->field_f_name[LANGUAGE_NONE][0]['value'] ;
$user_load->field_l_name[LANGUAGE_NONE][0]['value'] ;
$user_load->field_phone[LANGUAGE_NONE][0]['value'] ;
$user_load->field_address[LANGUAGE_NONE][0]['value']

Answer: A better way is using the Field API.
I'm not sure which variables are you handling on the page.tpl.php
As harsal says, you can use the global variable $user, but to access each field of the current  user, you could do it like this (for example for phone would be):
echo render(field_view_field('user', $user, 'field_phone', array('label' => 'hidden')));

Additional tip: to protect each field against XSS attacks, you cloud use the Drupal function filter_xss()


Is there a name for a policy where taxpayers decide who gets their money

Question: I was thinking about what the implications would be if everyone still has to pay the same amount of taxes as they do now. But for a portion of their taxes they can decide to give it to specific projects directly that in some way benefit society. For example parents could add more funding to their local school for additional services, construction projects and so on. Is there a name for such a system? Has this been tested and are there any studies about the results?
Comment: And how is defined what benefit society?
Comment: @convert Government budgets are usually distributed by department. So one could decide that x% of their taxes should go to the department of defense, y% to the department of agriculture, z% to the department of education, etc. - In theory! If that would be a useful system in practice would be something for a debate website.
Comment: [Sure it is implemented](https://ceeimpact.org/poland-1-percent-of-tax-does-it-really-make-a-difference/)
Comment: 90% of taxes are paid by about 10% of people; all this would do is effectively give the rich control of the government...
Answer: If people get a say on how their taxes are spent you'd probably just call that (direct) (economic) democracy, maybe a version of socialism. If they get a say on how their share of the taxes in particular are spend probably a variation of hyperindividualism and if unequally distributed probably something like a plutocracy.
But from how you describe it, it also sounds like a tax deduction, that is you paid money on necessary expenses that otherwise the state would need to cover or gifted to charity or whatnot and that can be subtracted from your taxable income. Though this is usually limited and doesn't include your entire taxes.


Mambo parrot /tello control propeller speeds

Question: From my understanding, for parrot mambo and tello drones, we control forward-backward, up-dow, left-right, and yaw speeds (in m/s and deg/s). But the low level control is control the 4 propeller speeds. I was wondering if there is a 1-1 map between these two control options, meaning that if I have the input for the 4 propeller speeds, I know the forward-backward, up-dow, left-right, and yaw speeds  and viceverse.
In this way, we would be able to control the low level even if the interface of these drones do not allow us to do it.
Thanks!
Comment: this question is a better fit at https://drones.stackexchange.com/
Answer: No, those two things are not 1:1. Remember that you have a dynamic system. The drone's current velocity can have a big impact on what happens to the propeller speeds when you give a new desired velocity.


$\lim_{n\to\infty} 1^n = 1$?

Question: Is it really true that
$$\lim_{n\to\infty} 1^n  = 1$$
?
We were taught throughout our entire math courses that $[1^{\infty}]$ is an undetermined form....Am I missing something here?
Comment: Actually, $\lim_{x\to\infty}1^n=1^n$.
Comment: yes, $\lim_{n\to\infty}1=1$.
Answer:
Is it really true that
  $$\lim_{\color{red}{x}\to\infty} 1^n  = 1$$

You probably mean:
$$\lim_{\color{blue}{n}\to\infty} 1^n  = 1$$
and yes, this is true because $1^n = 1$ for all $n$.
The expression $"1^{+\infty}"$ is indeterminate and the limit above doesn't contradict that.
Perhaps you know the following well-known limit too:
$$\lim_{n\to\infty}\left(\color{blue}{1+\frac{1}{n}}\right)^\color{red}{n} = e \ne1$$where you also have $\color{blue}{1+\frac{1}{n}}\to 1$ and $\color{red}{n}\to+\infty$.
Combining both limits shows that you can have sequences $c_n = \left(a_n\right)^{b_n}$ where $a_n \to 1$ and $b_n\to+\infty$ but with different limits for $c_n$; which is why we call $"1^{+\infty}"$ indeterminate.
Answer: You're clearly misunderstanding what an "indeterminate form" is. The fact that $1^\infty$ is an indeterminate form means that knowing $f(n)\to1$ and $g(n)\to \infty$ does not allow us to say anything in general about
$$\lim_n f(n)^{g(n)}$$
However, this does not mean that limits of this kind cannot exist. Examples:
$$\lim\limits_{n\to\infty} \left(1+\frac1n\right)^n = e $$
and your case
$$\lim\limits_{n\to\infty}1^n = 1. $$
Answer: You have to distinguish from purely a constant base $1$ to a power approaching infinity and a base that is a function approaching $1$ while its power approaches infinity (and dependent on the same limiting variable).
A constant can never change. A function can. This impacts your end result. Take the famous limit:
$$\lim_{n\to\infty} \left(1+\frac 1n\right)^n=e$$
Realize the base depends on $n$ to approach $1$ while the power also depends on $n$. Thus, the 'different rates of approachment' lead to unexpected results that make it indeterminate.
Answer: $$\lim_{n\rightarrow \infty}{1^n}=\lim_{n\rightarrow \infty}{1}=1$$
 Since $1^n=1 \ \forall n$, thus the limit is now independent of n and thus stays the same.

$\lim_{n\to\infty} 1^n = 1$?


I want to apply in this company because they provide international mobility. How should i write it?

Question: I'm a french student in industrial engineering, working in apprenticeship and I would like to go abroad for my first job. I heard, from another's company employee, they are searching for an industrial engineer for a 2 years mission in USA. However, I can't find this post on their website. I would like to submit a spontaneous application, but how should I write, in my cover letter, I want to apply only if a can go abroad ?
Answer: Just do it.
Mention that you heard from another employee about this job. There is nothing wrong with that.
And if the heading of your cover letter contains something like:

Application for industrial engineer for 2 years mission in USA

it is aboundently clear that you only want this job if you can go abroad.
Comment: Agreed. A lot of companies have a rather weird HR department when it comes to recruiting people. They are not always aware what job ads they have on other sites. However, applying for a company is never bad. I've applied to MANY companies that had no job offers and most of them were interested in me. Meaning I had a royal choice in where I wanted to work.


Too many SOQL queries: 101 in salesforce scheduled flow

Question: I have created a scheduled flow to update parent account on accounts based on a criteria but there is SOQL 101 error since trying to query the parent account inside the loop not sure how to resolve this and pull the related record for each account without looping
Comment: Why not just make this a Record-Triggered Flow instead?
Comment: since we cant control the sequence of insertion like parent and child records
Answer: Short Answer: You can't do this in a Flow.
Longer Answer: There's no such mechanism available in Flows like Apex's Map object. So, you're limited to two choices: query inside a loop, or pull out the Id values for the parents (one loop), then get those accounts, then use a nested loop to find the appropriate parent for each child. This has potentially multiplicative growth, meaning it will likely exceed either CPU limits or the 2,000 executed elements per Flow limit (as few as 65 child records could hit this limit).
You'll need some Apex code to make it efficient enough to work with the limits of Flows, and by the time you've written enough Apex to do this, you may as well just make it a Schedulable Apex class and skip the Flow parts.


KDE plasma graphics are not working properly

Question: So, I have recently purchased a new desktop (CPU: AMD Ryzen 7 1700x and GPU: Radeon RX470, I had an old Intel laptop before) and I've been experiencing persisting graphics performance issues. I installed Ubuntu 17.10, then after a couple of weeks I decided to switch my desktop environment from Gnome to KDE Plasma, but, to my surprise, all desktop effects were either sluggish or not working at all, not to mention the screen tearing while moving windows around or scrolling up and down. Since everything was working properly under gnome, I just thought it was a configuration issue, but everything I've tried so far has not helped:

I've tried to tweak the Xorg amdgpu.conf configuration file (I did this several times, many different combinations);
I uninstalled Ubuntu and installed Kubuntu (17.10) instead, then I tried installing the devel version (I know this is not recommended, but I thought maybe some upstream updates could tackle the problem), since nothing worked, I went back to Ubuntu 17.10;
I've also tried changing some compositor settings (like rendering backend, scale method, vsync);
At last I tried installing the AMDGPU-Pro driver, but (as many of you may already know) it breaks the whole system.

After all, I ended up going back to Gnome, but I wonder if there's anything else I could do to have plasma running perfectly as it did under Intel, or if this is an issue KDE has when running AMD hardware.
Thanks a lot for your time! If there's any other information tha'd be helpful to solve this issue, let me know and I'll post it.
Answer: The problem was solved after a couple kernel updates, so I'm assuming it had something to do with the firmware in it. Since Ryzen is, at the moment, cutting-edge hardware, that seems to be a reasonable assumption.
Well, I'm glad support for it has gotten so much better in such a short period of time!


Galois groups of polynomials and explicit equations for the roots

Question: Lets say I have calculated the galois group of some polynomial and I also have the subgroup structure. What's an effective procedure to turn the group into equations for the actual roots of the polynomial in terms of its coefficients assuming the galois group of the polynomial is solvable?
Comment: Ah, you have never seen even one example. In Dummit & Foote's Abstract Algebra they have an exercise which works out explicit formulas for the 17th roots of unity in terms of nested radicals. And you can find Galois-theoretic derivations of the cubic and quartic formulas by a simple Google search for "galois theory cubic formula". I personally think it's far more interesting that you can use Galois extensions to create 9-dimensional division rings (over the rational numbers) since the only division ring most non-algebraists have heard of, namely the real quaternions, has dimension 4.
Comment: @KCd: It seems odd to motivate the subject by saying things about roots of equations and how they can be expressed in terms of the coefficients if and only if the group is solvable and not have a single worked out example. During my studies I haven't found an example so that's why I asked.
Comment: Some examples of this might be worked out in the book "Galois Theory" by D. Cox. But why do you really want to do this? The reality is that Galois theory is not really designed to make that task straightforward or efficient. In fact Galois made that point himself in one of his letters. If I can dig up that citation I'll post it here later.
Comment: And since you write about not seeing an example in your studies, why not approach a local professor (perhaps the teacher of your algebra course) and ask in person how to get such examples?
Comment: @KCd: You are welcome to post your comment as an answer so I can close the question.
Comment: I have a feeling (correct me if I'm wrong) that KCd always posts his answers as comments.  If so (perhaps KCd can confirm), I suggest you paste the comment as a community wiki answer.
Answer: One of the fundamental techniques for doing this is to compute the (Lagrange) resolvants associated to the equation. Assuming the group is solvable, the resolvants will be factorizable and amenable to lower degree auxiliary equations. To have a first idea of all this, I would advice you to look at Harold Edwards splendid book : "Galois Theory" (ISBN 038790980X) where it does it for the elementary cases and an example of the cyclotomic equation.
With modern Computer Algebra System, one can more easily explore the idea further, but considerable ingenuity is needed because the degree of the auxiliary equations rise quickly.  Some CAS (such as GAP which is a free and open-source academic research tool) are able to give you the Galois groups of low degree polynomials, as well as properties of splitting fields and you can look at their tutorial to have examples of their use.
Effective and Inverse Galois Theory is still an active research subject. Some of the works by Annick Valibouze, N. Durov, Klueners, etc. might help you to go further.
Answer: The book Classical Galois theory: with examples by Gaal contains explicit computations, if not a complete algorithm.
Answer: I feel the book "Algebraic theories" by Dickson(now its coming in Dover phoenix edition) have some "Real" stuff about Galois theory in the sense that answers your question of explicit calculations.


How to setup a PC under Windows 10 to stream on Twitch using the XBOX app?

Question: I am trying to stream myself playing League of Legends using the XBox app on a Windows 10 PC, I heard it was possible but cannot manage to find the right setting. Has anyone else been there ?
Comment: On a side note, why not OBS ?
Comment: The XBox app allows me to easy handle the recording even using Cortana voice commands, but for now I can stream to a TV, a XBox, or even store games on my DVR. I would like to keep the same platform for everything.
Answer: Unfortunately from what I've seen, this feature isn't available yet.
Searching online for it shows some leaked screenshots hinting that it was being worked on, but as of the latest non-insider release (Creators Update), this is currently not in the feature set of Game DVR.

If you really want to stream, and don't mind not using Windows Game DVR, then I recommend you to check out OBS, XSplit or Gameshow. Configuration process of all three for twitch are documented on this page.


Is there any way to connect blender to processing?

Question: I would like to produce processing style effects in blender or other traditional applications, either 2d or 3d. I have been looking for ways to connect the language to blender through blender's internal python interpreter. So far I have found nothing. I even looked for ways to call jython libraries within blender, as processing.py is a jython wrapper around the java original, and the closest I have found was some information on blender java. I would much rather use an up to date more feature rich version of blender than a java port. Does any one know of a way to call jython from with in Cpython that would be compatible with blender or a java or javascript to python method that would work? Even the location of a pure python script that works like processing would be acceptable.
Answer: Maybe the question is a little off topic for the blender.stackexchange
There is python-osc for talking over OSC between Blender and any OSC supporting program (Processing comes with an OSC library). You could make your own bindings.
Comment: Thank you I will look into that. I am just curious though how well OSC handles visual media since it was designed for sound. I guess I will inquire about that over at python-osc.
Comment: @yehochanan consider the osc 'stream' more as a way to send higher level instructions from one program to another. Just like OSC isn't used to send samples, but you might send a filepath of a new sample to load - You might send condensed draw commands over OSC or again a filepath so Processing can read instructions from disk. (I/O is pretty fast these days)


How can I take out dog diarrhea stain from unfinished pine floor?

Question: My fog had an accident a few days ago on the unfinished pine floor we have in the living room. After cleaning it wish basic cleaning products it left quite a stain.
I would appreciate any kind of help into what products I should use and buy as soon as possible to restore the wood at least close to its original state!
Thank you!
Comment: Hello, and welcome to Home Improvement. This is  likely to be deemed off-topic, but that said my best solution would be to sand it off, and get a diaper for the dog.
Comment: tell everybody that it's a bloodstain from the last guy that annoyed you .... lol
Answer: Unfinished wood is tough because the nasties in the diarrhea have soaked into the wood fibers. to get the stain out you might end up bleaching the wood. I would try a weak hydrogen peroxide and water solution. Peroxide may take some of the color out but I think it would be less harmful than bleach and water. The products that take pet stains out of carpet probably won't work in this case. Another possibility is a real steam cleaner, my wife has a lady bug steam cleaner and it is amazing how well it works, a steam iron with a damp towel may work similarly. I think any stronger cleaners like trisodium phosphate will also bleach the coloring, since the floor was unfinished the stain might be fairly deep so I would try hydrogen peroxide 3% to water or steam cleaning prior to anything stronger.


Why glass is considered as an opaque body...?

Question: We know that the transmissivity of glass is 0 then also in general conditions it is taken as an opaque body and also in some books, it is taken as an opaque body.
Comment: Unclear what you are asking. But for thermal radiation (far infrared), glass i opaque. Also in the UV.
Answer: For any given chemical composition of what is called "glass" (and there are many different ones), each different composition will allow some wavelengths of light to pass through it while blocking other wavelengths.
For example, soda-lime glass (as commonly used in house windows) passes visible light but blocks a lot of the infrared. On the other hand, fused quartz glass passes both visible and much of the IR wavelengths, and so it is used for windows in things like wood stoves.