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Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
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Selecting last element in JavaScript array [duplicate]
...gth less 1.
Mozilla Docs on Slice
Performance of the various methods for selecting last array element
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Are Exceptions in C++ really slow
...cattered around memory, and complex operations to run (basically a dynamic_cast test for each handler)
So, mostly cache misses, and thus not trivial compared to pure CPU code.
Note: for more details, read the TR18015 report, chapter 5.4 Exception Handling (pdf)
So, yes, exceptions are slow on th...
Fetch frame count with ffmpeg
.... See Edit lists below.
ffprobe: Query the container
ffprobe -v error -select_streams v:0 -show_entries stream=nb_frames -of default=nokey=1:noprint_wrappers=1 input.mp4
This is a fast method.
Not all formats (such as Matroska) will report the number of frames resulting in the output of N/A. ...
How to get all columns' names for all the tables in MySQL?
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select * from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position
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REDHAT 6.4 X64下ORACLE 11GR2静默安装 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
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#
# all_langs : All languages
#
# Specify value as the following to select any of the languages.
# Example : SELECTED_LANGUAGES=en,fr,ja
#
# Specify value as the following to select all the languages.
# Example : SELECTED_LANGUAGES=all_langs
#---------------------------------------------...
MySQL indexes - what are the best practices?
...t them. Generally I put an index on any fields that I will be searching or selecting using a WHERE clause but sometimes it doesn't seem so black and white.
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How do I fix the Visual Studio compile error, “mismatch between processor architecture”?
... item.
Find your project in the list, under Platform it will say "Any CPU"
Select the "Any CPU" option from the drop down and then select <New..>
From that dialog, select x86 from the "New Platform" drop down and make sure "Any CPU" is selected in the "Copy settings from" drop down.
Hit OK
You...
Can you grab or delete between parentheses in vi/vim?
...motion commands by entering :help various-motions in command mode.
object-select
There is another set of motion commands that you can use in Visual mode to select various text objects.
To solve your specific problem you would do the following:
printf("%3.0f\t%6.1f\n", fahr, ((5.0/9.0) * (fahr-32...
Visual Studio opens the default browser instead of Internet Explorer
...er:
1) Right click on a .aspx page in your
solution explorer
2) Select the "browse with" context
menu option
3) In the dialog you can select or add
a browser. If you want Firefox in the
list, click "add" and point to the
firefox.exe filename
4) Click the "Set as Default...