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Extract month and year from a zoo::yearmon object
... "%m"))
[1] 3
> as.numeric(format(date1, "%Y"))
[1] 2012
See ?yearmon and ?strftime for details - the latter explains the placeholder characters you can use.
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Python executable not finding libpython shared library
I am installing Python 2.7 on CentOS 5. I built and installed Python as follows
9 Answers
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What does %~dp0 mean, and how does it work?
I find %~dp0 very useful, and I use it a lot to make my batch files more portable.
7 Answers
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PHP best way to MD5 multi-dimensional array?
... is two-fold here as (1) json_encode alone performs faster than serialize, and (2) json_encode produces a smaller string and therefore less for md5 to handle.
Edit: Here is evidence to support this claim:
<?php //this is the array I'm using -- it's multidimensional.
$array = unserialize('a:6:{i...
pandas read_csv and filter columns with usecols
I have a csv file which isn't coming in correctly with pandas.read_csv when I filter the columns with usecols and use multiple indexes.
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Can I use multiple versions of jQuery on the same page?
...f jQuery to a different alias). How the customer is using jQuery will vary and is outside of my control. Can I safely just use the latter half, or do both libraries need to call noConflict()?
– Bungle
Oct 14 '09 at 15:05
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ETag vs Header Expires
...d around but haven't been able to figure out if I should use both an ETag and an Expires Header or one or the other.
8 ...
Python to print out status bar and percentage
...character (carriage return) resets the cursor to the beginning of the line and allows you to write over what was previously on the line.
from time import sleep
import sys
for i in range(21):
sys.stdout.write('\r')
# the exact output you're looking for:
sys.stdout.write("[%-20s] %d%%" %...
What's the difference between identifying and non-identifying relationships?
...t been able to fully grasp the differences. Can you describe both concepts and use real world examples?
15 Answers
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What is the benefit of using Fragments in Android, rather than Views?
When developing for Android , you can set your target (or minimum) sdk to 4 (API 1.6) and add the android compatibility package (v4) to add support for Fragments . Yesterday I did this and successfully implemented Fragments to visualize data from a custom class.
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