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Modifying a subset of rows in a pandas dataframe
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248
Use .loc for label based indexing:
df.loc[df.A==0, 'B'] = np.nan
The df.A==0 expression cre...
How can I read command line parameters from an R script?
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210
Dirk's answer here is everything you need. Here's a minimal reproducible example.
I made two ...
How to export all collections in MongoDB?
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26 Answers
26
Active
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Manually raising (throwing) an exception in Python
...error: ValueError('Represents a hidden bug, do not catch this',)
Problem 2: Won't catch
And more specific catches won't catch the general exception:
def demo_no_catch():
try:
raise Exception('general exceptions not caught by specific handling')
except ValueError as e:
pri...
Select multiple records based on list of Id's with linq
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214
You can use Contains() for that. It will feel a little backwards when you're really trying to...
Which cryptographic hash function should I choose?
...flaw that allows collisions to be found in theoretically far less than the 2^80 steps a secure hash function of its length would require. The attack is continually being revised and currently can be done in ~2^63 steps - just barely within the current realm of computability. For this reason NIST is ...
How to discover number of *logical* cores on Mac OS X?
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812
You can do this using the sysctl utility:
sysctl -n hw.ncpu
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Regular expression to match numbers with or without commas and decimals in text
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293
EDIT: Since this has gotten a lot of views, let me start by giving everybody what they Googled...
Creating an R dataframe row-by-row
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edited Feb 18 '19 at 2:37
Neil
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answered Sep...
iOS multiline label in Interface builder
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answered Jul 2 '11 at 14:27
akashivskyyakashivskyy
39k1414 gold badges101101 silver badges113113 bronze badges
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