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In MySQL, can I copy one row to insert into the same table?
...an existing row in the table) but I want to do this without having to list all the columns after the "select", because this table has too many columns.
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Command-line Unix ASCII-based charting / plotting tool
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While gnuplot is powerful, it's also really irritating when you just want to pipe in a bunch of points and get a graph.
Thankfully, someone created eplot (easy plot), which handles all the nonsense for you.
It doesn't seem to have an option to force terminal gra...
Transposing a NumPy array
...of a 1D array is still a 1D array! (If you're used to matlab, it fundamentally doesn't have a concept of a 1D array. Matlab's "1D" arrays are 2D.)
If you want to turn your 1D vector into a 2D array and then transpose it, just slice it with np.newaxis (or None, they're the same, newaxis is just mor...
What does FETCH_HEAD in Git mean?
...it like doing git fetch without arguments (or git remote update), updating all your remote branches, then running git merge origin/<branch>, but using FETCH_HEAD internally instead to refer to whatever single ref was fetched, instead of needing to name things.
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In which situations do we need to write the __autoreleasing ownership qualifier under ARC?
...ents that are passed by reference (id *) and are autoreleased on return.
All of this is very well explained in the ARC transition guide.
In your NSError example, the declaration means __strong, implicitly:
NSError * e = nil;
Will be transformed to:
NSError * __strong error = nil;
When you c...
ASP.NET Identity's default Password Hasher - How does it work and is it secure?
...ff using decimal numbers is A LOT more intuitive (we have 10 fingers after all - at least most of us), so declaring a number of something using hexadecimals seems like an unnecessary code obfuscation.
– Andrew Cyrul
Apr 13 '17 at 9:27
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Why does Windows64 use a different calling convention from all other OSes on x86-64?
AMD has an ABI specification that describes the calling convention to use on x86-64. All OSes follow it, except for Windows which has it's own x86-64 calling convention. Why?
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How to add an integer to each element in a list?
...ition, but if you have a more complex function that you needed to apply to all the elements then map may be a good fit.
In your example it would be:
>>> map(lambda x:x+1, [1,2,3])
[2,3,4]
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Injecting a mock into an AngularJS service
...e.
If you have the following service with a dependency that has a method called getSomething:
angular.module('myModule', [])
.factory('myService', function (myDependency) {
return {
useDependency: function () {
return myDependency.getSomething();
}...
Encoding an image file with base64
... here is an update after you have edited your original question.
First of all, remember to use raw strings (prefix the string with 'r') when using path delimiters on Windows, to prevent accidentally hitting an escape character. Second, PIL's Image.open either accepts a filename, or a file-like (tha...