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How to add an empty column to a dataframe?
...p
>>> import pandas as pd
>>> df = pd.DataFrame({"A": [1,2,3], "B": [2,3,4]})
>>> df
A B
0 1 2
1 2 3
2 3 4
>>> df["C"] = ""
>>> df["D"] = np.nan
>>> df
A B C D
0 1 2 NaN
1 2 3 NaN
2 3 4 NaN
...
Why do people say there is modulo bias when using a random number generator?
...Now what happens if you want to generate a random number between say 0 and 2? For the sake of explanation, let's say RAND_MAX is 10 and I decide to generate a random number between 0 and 2 by calling rand()%3. However, rand()%3 does not produce the numbers between 0 and 2 with equal probability!
W...
Why are floating point numbers inaccurate?
...
250
In most programming languages, floating point numbers are represented a lot like scientific no...
How do I compare two DateTime objects in PHP 5.2.8?
...
<?php
date_default_timezone_set('Europe/London');
$d1 = new DateTime('2008-08-03 14:52:10');
$d2 = new DateTime('2008-01-03 11:11:10');
var_dump($d1 == $d2);
var_dump($d1 > $d2);
var_dump($d1 < $d2);
?>
bool(false)
bool(true)
bool(false)
dev:~# php -v
PHP 5.2.6-1+lenny3 with Suhosin-Pa...
NTFS performance and large volumes of files and directories
...
274
Here's some advice from someone with an environment where we have folders containing tens of m...
Removing projects in Sublime Text 2 and 3
How do you remove a project from Sublime Text 2 and 3's project windows ( Ctrl + Alt + P ) ?
5 Answers
...
How can I check which version of Angular I'm using?
...
28 Answers
28
Active
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String's Maximum length in Java - calling length() method
... that would be returned by the method would be Integer.MAX_VALUE, which is 2^31 - 1 (or approximately 2 billion.)
In terms of lengths and indexing of arrays, (such as char[], which is probably the way the internal data representation is implemented for Strings), Chapter 10: Arrays of The Java Langu...
Pandas groupby: How to get a union of strings
...s+')
In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When you apply your own functi...
Oracle JDBC ojdbc6 Jar as a Maven Dependency
...>
<artifactId>ojdbc6</artifactId>
<version>11.2.0.3</version>
</dependency>
...
<repositories>
<repository>
<id>codelds</id>
<url>https://code.lds.org/nexus/content/groups/main-repo</url>
</repositor...