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What is the difference between NaN and None?
... a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead nan is assigned. Surely None is more descriptive of an empty cell as it has a null value, whe...
Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
...uld be noticeable impact.
Enumerable.Empty does not create an object per call thus putting less load on GC.
If the code is in low-throughput location, then it boils down to aesthetic considerations though.
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How do I get bit-by-bit data from an integer value in C?
...ude <stdlib.h>
int *get_bits(int n, int bitswanted){
int *bits = malloc(sizeof(int) * bitswanted);
int k;
for(k=0; k<bitswanted; k++){
int mask = 1 << k;
int masked_n = n & mask;
int thebit = masked_n >> k;
bits[k] = thebit;
}
return bits;
}
in...
How to display loading message when an iFrame is loading?
...
It depends on the user's needs. If he don't need all images to be loaded before he hide the loading message then he won't need the on load callback.
– Minko Gechev
Jul 25 '12 at 12:55
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Determining type of an object in ruby
... the "type" of an object, which is a wobbly term in the Ruby world, is to call object.class.
Since classes can inherit from other classes, if you want to determine if an object is "of a particular type" you might call object.is_a?(ClassName) to see if object is of type ClassName or derived from it....
pandas: filter rows of DataFrame with operator chaining
...
That is a really nice solution - I wasn't even aware that you could jury-rig methods like that in python. A function like this would be really nice to have in Pandas itself.
– naught101
Mar 3 '17 at...
Unit Test? Integration Test? Regression Test? Acceptance Test?
...plicable:
Unit Test
A unit test is performed on a self-contained unit (usually a class or method) and should be performed whenever a unit has been implemented or updating of a unit has been completed.
This means it's run whenever you've written a class/method, fixed a bug, changed functionality......
check android application is in foreground or not? [duplicate]
I went through a lot of answers for this question.But it's all about single activity..How to check whether the whole app is running in foreground or not ?
...
undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
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Why rgb and not cmy? [closed]
...mary colors are cyan, magenta and yellow (CMY), why do monitors and almost all the GUI components out there use red, green and blue (RGB)? (If I'm not mistaken, printers use the CMYK model.)
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