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How to group dataframe rows into list in pandas groupby?
..., x, y]
C [6] [z]
To group-listify a single column only, convert the groupby to a SeriesGroupBy object, then call SeriesGroupBy.agg. Use,
df.groupby('a').agg({'b': list}) # 4.42 ms
df.groupby('a')['b'].agg(list) # 2.76 ms - faster
a
A [1, 2]
B [5, 5, 4]
C [...
How do I do a multi-line string in node.js?
...for me, is the same thing wrong with Groovy last I checked. When a file is converted from .coffee to .js, the line numbers are jumbled. I have not tried CoffeeScript, but when I tried Groovy, I found it quite difficult to debug without getting the generated .java files.
– Bryan...
Get file name and extension in Ruby
I'm working on a program to download a video from YouTube, convert it to MP3 and create a directory structure for the files.
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Action bar navigation modes are deprecated in Android L
Taking a look at the API diff report for the Android "L" preview, I see that all methods related to navigation modes in the ActionBar class (such as setNavigationMode() , addTab() , selectTab() , &c). are now deprecated.
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How do you make a deep copy of an object?
... final or can't be modified, extend the class and implement serializable.
Convert your class to a stream of bytes:
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(object);
oos.flush();
oos.close();
bos.close();
byte[] b...
How to use GROUP_CONCAT in a CONCAT in MySQL
...SEPARATOR ',') AS result
FROM test GROUP BY id
you must use cast or convert, otherwise will be return BLOB
result is
id Column
1 A:4,A:5,B:8
2 C:9
you have to handle result once again by program such as python or java
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Is there a __CLASS__ macro in C++?
... That's a pity it isn't defined like __ CLASS __ , it can be handy at preprocessor stage! :(
– k3a
Aug 23 '10 at 11:51
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Google Docs/Drive - number the headings
...
@MrGravity the way to achieve that is to convert the script into a Add-On for Google Drive I plan in doing that but am out of time now..
– Luciano
Jul 11 '14 at 14:21
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String variable interpolation Java [duplicate]
...ould be $, % or @. Java would only print such characters,
it would not expand them.
Variable interpolation is not supported in Java. Instead of this, we
have string formatting.
package com.zetcode;
public class StringFormatting
{
public static void main(String[] args)
{
int a...
Checking to see if one array's elements are in another array in PHP
... why in PHP docs about this function they say "Returns FALSE if var exists and has a non-empty, non-zero value. Otherwise returns TRUE. The following things are considered to be empty: array() (an empty array)"? Source: php.net/manual/en/function.empty.php
– Pere
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