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How to compare two dates?
...t; datetime(3000, 1, 1) < present
False
>>> present - datetime(2000, 4, 4)
datetime.timedelta(4242, 75703, 762105)
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How to create a bash script to check the SSH connection?
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12 Answers
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What is the difference between gmake and make?
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edited Jul 28 '09 at 19:21
dmckee --- ex-moderator kitten
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Can “list_display” in a Django ModelAdmin display attributes of ForeignKey fields?
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edited Jul 25 '14 at 16:10
Denilson Sá Maia
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What does “exited with code 9009” mean during this build?
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Switch statement fallthrough in C#?
... 0), or using the special goto case (see case 1) or goto default (see case 2) forms:
switch (/*...*/) {
case 0: // shares the exact same code as case 1
case 1:
// do something
goto case 2;
case 2:
// do something else
goto default;
default:
//...
String concatenation vs. string substitution in Python
...meit.Timer('so_q_sub(1000)','from __main__ import so_q_sub')
>>> t2 = timeit.Timer('so_q_cat(1000)','from __main__ import so_q_cat')
>>> t1.timeit(number=10000000)
12.166618871951641
>>> t2.timeit(number=10000000)
5.7813972166853773
>>> t1.timeit(number=1)
1.10349...
How do I get an empty array of any size in python?
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If by "array" you actually mean a Python list, you can use
a = [0] * 10
or
a = [None] * 10...
Determine the number of NA values in a column
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321
You're over-thinking the problem:
sum(is.na(df$col))
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