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Assigning a variable NaN in python without numpy
...= nan
False
>>> import math
>>> math.isnan(nan)
True
Before Python 3.5, one could use float("nan") (case insensitive).
Note that checking to see if two things that are NaN are equal to one another will always return false. This is in part because two things that are "not a numbe...
Javascript Drag and drop for touch devices [closed]
I am looking for a drag & DROP plugin that works on touch devices.
5 Answers
5
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Resolve build errors due to circular dependency amongst classes
...lasses in different header files (can happen also in the same file) . But fortunately(?) this doesn't happen often enough for me to remember the solution to this problem for the next time it happens again.
...
Saving an Object (Data persistence)
...eferable to actually use the cPickle module rather than pickle because the former is written in C and is much faster. There are some subtle differences between them, but in most situations they're equivalent and the C version will provide greatly superior performance. Switching to it couldn't be eas...
Dynamically set local variable [duplicate]
...ctionary lookups (as Sven points out in the comments there are exceptions, for example classes that define __slots__). Function locals can be optimised for speed because the compiler (usually) knows all the names in advance, so there isn't a dictionary until you call locals().
In the C implementati...
What's the difference between a Python module and a Python package?
...my_package.timing.danger.internets import function_of_love
Documentation for modules
Introduction to packages
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Most efficient way to remove special characters from string
...haracters(this string str) {
StringBuilder sb = new StringBuilder();
foreach (char c in str) {
if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '.' || c == '_') {
sb.Append(c);
}
}
return...
append multiple values for one key in a dictionary [duplicate]
I am new to python and I have a list of years and values for each year. What I want to do is check if the year already exists in a dictionary and if it does, append the value to that list of values for the specific key.
...
Transposing a 2D-array in JavaScript
...ow => row[colIndex]));
map calls a provided callback function once for each element in an array, in order, and constructs a new array from the results. callback is invoked only for indexes of the array which have assigned values; it is not invoked for indexes which have been deleted or which...
Starting python debugger automatically on error
This is a question I have wondered about for quite some time, yet I have never found a suitable solution. If I run a script and I come across, let's say an IndexError, python prints the line, location and quick description of the error and exits. Is it possible to automatically start pdb when an err...