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How do I check if a number evaluates to infinity?
...lert(x === Infinity); displays "true". (Admittedly that's an obscure case, and anyone who decides to redefine Infinity, NaN etc should expect odd things to happen.)
– LukeH
Jan 18 '11 at 13:49
...
How to exclude a directory in find . command
I'm trying to run a find command for all JavaScript files, but how do I exclude a specific directory?
38 Answers
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Split comma-separated strings in a column into separate rows
...odified according to Rich Scriven's comment,
Jaap's two data.table methods and two dplyr / tidyr approaches,
Ananda's splitstackshapesolution,
and two additional variants of Jaap's data.table methods.
Overall 8 different methods were benchmarked on 6 different sizes of data frames using the micro...
Assigning variables with dynamic names in Java
...However, this only works for variables that are class members (i.e. static and instance fields). It doesn't work for local variables. See @fyr's "quick and dirty" example.
However doing this kind of thing unnecessarily in Java is a bad idea. It is inefficient, the code is more complicated, and s...
Why is iostream::eof inside a loop condition (i.e. `while (!stream.eof())`) considered wrong?
...ndicate, that the next read will be the end of the stream.
Consider this (and assume then next read will be at the end of the stream):
while(!inStream.eof()){
int data;
// yay, not end of stream yet, now read ...
inStream >> data;
// oh crap, now we read the end and *only* now the eo...
How to find the largest file in a directory and its subdirectories?
We're just starting a UNIX class and are learning a variety of Bash commands. Our assignment involves performing various commands on a directory that has a number of folders under it as well.
...
Extract subset of key-value pairs from Python dictionary object?
...bigdict.get(k, None) for k in ('l', 'm', 'n')}
If you're using Python 3, and you only want keys in the new dict that actually exist in the original one, you can use the fact to view objects implement some set operations:
{k: bigdict[k] for k in bigdict.keys() & {'l', 'm', 'n'}}
...
How to concatenate multiple lines of output to one line?
If I run the command cat file | grep pattern , I get many lines of output. How do you concatenate all lines into one line, effectively replacing each "\n" with "\" " (end with " followed by space)?
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How do I check if an integer is even or odd? [closed]
... if (x % 2)
printf("%d is odd\n", x);
return 0;
}
/* and.c */
#include <stdio.h>
int main(void)
{
int x;
for (x = 0; x < 10; x++)
if (x & 1)
printf("%d is odd\n", x);
return 0;
}
I then compiled these with gcc 4.1.3 on one of my m...
How to print like printf in Python3?
...
In both versions, % is an operator which requires a string on the left-hand side and a value or a tuple of values or a mapping object (like dict) on the right-hand side.
So, your line ought to look like this:
print("a=%d,b=%d" % (f(x,n),g(x,n)))
Also, the recommendation for Python3 and newer ...