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// see http://www.johndcook.com/IEEE_exceptions_in_cpp.html for details

bool IsNumber(double x) 
{
        // This looks like it should always be true, 
        // but it's false if x is a NaN.
        return (x == x); 
}

#include <float.h>

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def is_number(s):
    try:
        float(s)
        return True
    except ValueError:
        return False

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import subprocess
def call_command(command):
    process = subprocess.Popen(command.split(' '),
                               stdout=subprocess.PIPE,
                               stderr=subprocess.PIPE)
    return process.communicate()

# An example
if __name__ == "__main__":
     

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#include <unistd.h>

// Check whether file exist
// http://stackoverflow.com/questions/230062/whats-the-best-way-to-check-if-a-file-exists-in-c-cross-platform

if( access( fname, F_OK ) != -1 ) {
    // file exists
} else {
    // file doesn't exist
}

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"""BFS.py

Breadth First Search. See also LexBFS.py.

D. Eppstein, May 2007.
"""

try:
    set
except NameError:

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# http://stackoverflow.com/questions/893417/item-frequency-count-in-python
# defaultdict will automatically initialize values to zero.

from collections import defaultdict

words = "apple banana apple strawberry banana lemon"

d = defaultdict(int)
for word in words.split():
    d[word] += 1

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# http://docs.python.org/faq/programming.html#how-do-you-remove-duplicates-from-a-list
mylist = list(set(mylist))

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# http://stackoverflow.com/questions/613183/python-sort-a-dictionary-by-value
# http://wiki.python.org/moin/HowTo/Sorting/


import operator
x = {1: 2, 3: 4, 4:3, 2:1, 0:0}

sorted_x = sorted(x.iteritems(), key=operator.itemgetter(1),reverse=True)

y = [ ('john', 'A', 15), ('jane', 'B', 12), ('dave', 'B', 10),]