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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,
...
Array vs. Object efficiency in JavaScript
I have a model with possibly thousands of objects. I was wondering what would be the most efficient way of storing them and retrieving a single object once I have it's id. The id's are long numbers.
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How many String objects will be created when using a plus sign?
...;
Furthermore, the compiler will remove extraneous constant expressions, and only emit them if they are used or exposed. For instance, this program:
const String one = "1";
const String two = "1";
const String result = one + two + "34";
public static void main(string[] args) {
Console.Out.W...
IntelliJ IDEA way of editing multiple lines
I've seen this done in TextMate and I was wondering if there's a way to do it in IDEA.
20 Answers
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What is the difference between build.sbt and build.scala?
I started to learn Scala and almost in every tutorial I see a build.sbt file which describes project settings. But now I have installed giter8 and created a project from template. And generated project from template missed build.sbt file, but it have build.scala (which seems used for same pu...
Explanation of BASE terminology
...e system unavailable (or inconsistent). So you can see that 'availability' and 'partition tolerance' go hand in hand. There's more detail on this in this article.
– Niels van der Rest
Apr 14 '14 at 18:29
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Python Infinity - Any caveats?
So Python has positive and negative infinity:
5 Answers
5
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Safe integer parsing in Ruby
I have a string, say '123' , and I want to convert it to the integer 123 .
8 Answers
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Android SDK installation doesn't find JDK
I'm trying to install the Android SDK on my Windows 7 x64 System.
45 Answers
45
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Adding days to $Date in PHP
... ' + 1 days'));
echo date('Y-m-d', strtotime($Date. ' + 2 days'));
?>
And it outputs correctly:
2010-09-18
2010-09-19
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