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Pandas conditional creation of a series/dataframe column
...color'] = np.where(df['Set']=='Z', 'green', 'red')
For example,
import pandas as pd
import numpy as np
df = pd.DataFrame({'Type':list('ABBC'), 'Set':list('ZZXY')})
df['color'] = np.where(df['Set']=='Z', 'green', 'red')
print(df)
yields
Set Type color
0 Z A green
1 Z B green
2 ...
Volley Android Networking Library
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$ git clone https://android.googlesource.com/platform/frameworks/volley
$ cd volley
$ android update project -p .
$ ant jar
Then, copy bin/volley.jar into your libs/ folder and off you go!
source
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Understanding generators in Python
I am reading the Python cookbook at the moment and am currently looking at generators. I'm finding it hard to get my head round.
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Postgres: INSERT if does not exist already
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Postgres 9.5 (released since 2016-01-07) offers an "upsert" command, also known as an ON CONFLICT clause to INSERT:
INSERT ... ON CONFLICT DO NOTHING/UPDATE
It solves many of the subtle problems you can run into when using concurrent operation, which some other answers propose.
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Dependency Injection vs Factory Pattern
... when it comes to usage/design the difference between dependency injection and factory is blurred or thin.
28 Answers
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How can I see what has changed in a file before committing to git?
...ere are three useful ways to use git diff:
Show differences between index and working tree; that is, changes you haven't staged to commit:
git diff [filename]
Show differences between current commit and index; that is, what you're about to commit (--staged does exactly the same thing, use what y...
Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
...arison/branch. Whether it'll really improve speed may be open to question, and even if it does, it's probably too little to notice or care about, but when you're only starting with two comparisons, the chances of a huge improvement are pretty remote. The code looks like:
// use a < for an inclus...
Installing SetupTools on 64-bit Windows
I'm running Python 2.7 on Windows 7 64-bit, and when I run the installer for setuptools it tells me that Python 2.7 is not installed. The specific error message is:
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How to shrink the .git folder
...gressive --prune, which will perform garbage collection in your repository and prune old objects. do you have a lot of binary files (archives, images, executables) which change often? those usually lead to huge .git folders (remember, git stores snapshots for each revision and binary files compress ...
Add margin above top ListView item (and below last) in Android
This is a pretty fine question about the layout of items in a ListView in Android.
5 Answers
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