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How do I retrieve the number of columns in a Pandas data frame?
...so:
import pandas as pd
df = pd.DataFrame({"pear": [1,2,3], "apple": [2,3,4], "orange": [3,4,5]})
len(df.columns)
3
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C# nullable string error
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304
System.String is a reference type and already "nullable".
Nullable<T> and the ? suffix ar...
What's the difference between belongs_to and has_one?
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They essentially do the same thing, the only difference is what side of the relationship you ar...
Will HTML5 allow web apps to make peer-to-peer HTTP connections?
...thjrharshath
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45
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C# version of java's synchronized keyword?
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476
First - most classes will never need to be thread-safe. Use YAGNI: only apply thread-safety wh...
Using the slash character in Git branch name
...basically this:
% cd .git/refs/heads
% ls -l
total 0
-rw-rw-r-- 1 jhe jhe 41 2009-11-14 23:51 labs
-rw-rw-r-- 1 jhe jhe 41 2009-11-14 23:51 master
% mkdir labs
mkdir: cannot create directory 'labs': File exists
You're getting the equivalent of the "cannot create directory" error.
When you h...
Use of 'use utf8;' gives me 'Wide character in print'
...from this:
$ perl -E 'say join ":", map { ord } split //, "鸡\n";'
233:184:161:10
The first three bytes make up your character, the last one is the line-feed.
The call to print sends these four characters to STDOUT. Your console then works out how to display these characters. If your console is...
AngularJS: ng-repeat list is not updated when a model element is spliced from the model array
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edited Jul 9 '16 at 14:23
Peter Mortensen
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How to redirect output with subprocess in Python?
... Marcelo CantosMarcelo Cantos
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If I have ACCESS_FINE_LOCATION already, can I omit ACCESS_COARSE_LOCATION?
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149
https://developer.android.com/guide/topics/location/strategies.html#Permission
Note: If you...