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Append column to pandas dataframe
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@BenDundee Join and concat use a lot of the same code under the hood, so the "right" way probably only matters when you consider edge cases. For instance here if both DataFrames had a 'data' column the join would fail, whereas a concat would...
Declare and Initialize String Array in VBA
...Array( "Cat", "Dog" , "Rabbit"). Variants - yuck!
– Andez
Sep 19 '14 at 10:03
31
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Else clause on Python while statement
...as an if/else construct with respect to the condition:
if condition:
handle_true()
else:
handle_false()
is analogous to the looping construct:
while condition:
handle_true()
else:
# condition is false now, handle and go on with the rest of the program
handle_false()
An exam...
MongoDB logging all queries
...d parameter to -1, like db.setProfilingLevel(2,-1)
– andresigualada
Apr 12 '16 at 10:42
4
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How can I connect to Android with ADB over TCP? [closed]
... USB. My development server is a Windows 7 64-bit VM running in Hyper-V , and so I cannot connect directly via USB in the guest or from the host.
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How do I apply a diff patch on Windows?
...ng a heck of a time trying to apply one. I'm trying to distribute a patch, and I got a question from a user about how to apply it. So I tried to figure it out on my own and found out that I have no clue, and most of the tools I can find are command-line. (I can handle a command line, but a lot of pe...
How do you add an array to another array in Ruby and not end up with a multi-dimensional result?
...*a2) # note the asterisk
a2.unshift(*a1) # note the asterisk, and that a2 is the receiver
or splice:
a1[a1.length, 0] = a2
a1[a1.length..0] = a2
a1.insert(a1.length, *a2)
or append and flatten:
(a1 << a2).flatten! # a call to #flatten instead would return a new array
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Pandas percentage of total with groupby
...calculate the percentage in a simpler way -- just groupby the state_office and divide the sales column by its sum. Copying the beginning of Paul H's answer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
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Python Infinity - Any caveats?
So Python has positive and negative infinity:
5 Answers
5
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Versioning SQL Server database
....html. I choose not to put schema dumps in under version control as alumb and others suggest because I want an easy way to upgrade my production database.
For a web application where I'll have a single production database instance, I use two techniques:
Database Upgrade Scripts
A sequence databa...