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What is the difference between Modal and Push segue in Storyboards?
... navigation controller and the VC being presented modally is generally considered to be a "child" of the presenting (parent) VC. The modally presented VC is usually sans any navigation bars or tab bars. The presenting VC is also responsible for dismissing the modal VC it created and presented.
Ho...
How do I check if a string is valid JSON in Python?
In Python, is there a way to check if a string is valid JSON before trying to parse it?
4 Answers
...
Why is there no GIL in the Java Virtual Machine? Why does Python need one so bad?
I'm hoping someone can provide some insight as to what's fundamentally different about the Java Virtual Machine that allows it to implement threads nicely without the need for a Global Interpreter Lock (GIL), while Python necessitates such an evil.
...
Where is Python's sys.path initialized from?
...ly set sys.path. How it is
set can get really complicated. The following guide is a watered-down,
somewhat-incomplete, somewhat-wrong, but hopefully-useful guide
for the rank-and-file python programmer of what happens when python
figures out what to use as the initial values of sys.path,
sys.executa...
Choice between vector::resize() and vector::reserve()
... you want an array to which you expect to insert 1000 items and want to avoid a couple of allocations, use reserve().
EDIT: Blastfurnace's comment made me read the question again and realize, that in your case the correct answer is don't preallocate manually. Just keep inserting the elements at the...
How to pass a single object[] to a params object[]
..." parameter. This would allow you to pass multiple arrays as arguments:
void Foo( params object[][] arrays ) {
foreach( object[] array in arrays ) {
// process array
}
}
...
Foo( new[] { "1", "2" }, new[] { "3", "4" } );
// Equivalent to:
object[][] arrays = new[] {
new[] { "1", "2" },
...
How to print to console in pytest?
...result of standard out so that it can control how it prints it out. If it didn't do this, it would spew out a lot of text without the context of what test printed that text.
However, if a test fails, it will include a section in the resulting report that shows what was printed to standard out in th...
Adding an arbitrary line to a matplotlib plot in ipython notebook
...of the segments):
plot([x1, x2], [y1, y2], color='k', linestyle='-', linewidth=2)
(of course you can choose the color, line width, line style, etc.)
From your example:
import numpy as np
import matplotlib.pyplot as plt
np.random.seed(5)
x = np.arange(1, 101)
y = 20 + 3 * x + np.random.normal(0,...
Passing arguments forward to another javascript function
...
The arguments object contains one element for each actual parameter provided to the function. When you call a you supply three arguments: the numbers 1, 2, and, 3. So, arguments contains [1, 2, 3].
function a(args){
console.log(arguments) // [1, 2, 3]
b(arguments);
}
When you call b, h...
Python strptime() and timezones?
...umentation now also states the following:
When the %z directive is provided to the strptime() method, an aware datetime object will be produced. The tzinfo of the result will be set to a timezone instance.
Note that this doesn't work with %Z, so the case is important. See the following example...