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How do I create test and train samples from one dataframe with pandas?
...ering how I would be able to split the dataframe into two random samples (80% and 20%) for training and testing.
23 Answers...
Performance of Arrays vs. Lists
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List/for: 1971ms (589725196)
Array/for: 1864ms (589725196)
List/foreach: 3054ms (589725196)
Array/foreach: 1860ms (589725196)
based on the test rig:
using System;
using System.Collections.Generic;
using System.Diagnostics;
static class Program
{
static void Main()
{
List<int&g...
How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
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+100
I'll consider the problem of many<->one/many casemappings first and separately from handling different Normalization forms.
Fo...
Algorithm to get the excel-like column name of a number
...
10 Answers
10
Active
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Why does parseInt yield NaN with Array#map?
...ex of the element.
In this case, you ended up calling parseInt with radix 0, 1 and 2 in turn. The first is the same as not supplying the parameter, so it defaulted based on the input (base 10, in this case). Base 1 is an impossible number base, and 3 is not a valid number in base 2:
parseInt('1'...
How to write a cron that will run a script every day at midnight?
...how to use it on Ubuntu. Your crontab line will look something like this:
00 00 * * * ruby path/to/your/script.rb
(00 00 indicates midnight--0 minutes and 0 hours--and the *s mean every day of every month.)
Syntax:
mm hh dd mt wd command
mm minute 0-59
hh hour 0-23
dd day of month 1-...
Controlling maven final name of jar artifact
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303
You set the finalName property in the plugin configuration section:
<plugin>
<gro...
How can I count the number of matches for a regex?
... following. (Starting from Java 9, there is a nicer solution)
int count = 0;
while (matcher.find())
count++;
Btw, matcher.groupCount() is something completely different.
Complete example:
import java.util.regex.*;
class Test {
public static void main(String[] args) {
String hel...
Getting random numbers in Java [duplicate]
I would like to get a random value between 1 to 50 in Java.
2 Answers
2
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List comprehension on a nested list?
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answered Aug 6 '13 at 6:05
Andrew ClarkAndrew Clark
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