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How can I create a correlation matrix in R?
I have 92 set of data of same type.
5 Answers
5
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count the frequency that a value occurs in a dataframe column
...ame({'a':list('abssbab')})
df.groupby('a').count()
Out[37]:
a
a
a 2
b 3
s 2
[3 rows x 1 columns]
See the online docs: http://pandas.pydata.org/pandas-docs/stable/groupby.html
Also value_counts() as @DSM has commented, many ways to skin a cat here
In [38]:
df['a'].value_counts()
Out[...
Maximum length for MySQL type text
...
772
See for maximum numbers:
http://dev.mysql.com/doc/refman/5.0/en/storage-requirements.html
TINYB...
How to check if a string contains a substring in Bash
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26 Answers
26
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How to do exponential and logarithmic curve fitting in Python? I found only polynomial fitting
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230
For fitting y = A + B log x, just fit y against (log x).
>>> x = numpy.array([1, 7, ...
Best way to represent a fraction in Java?
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26 Answers
26
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EC2 Instance Cloning
Is it possible to clone a EC2 instance data and all?
7 Answers
7
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Which is better option to use for dividing an integer number by 2?
... of the following techniques is the best option for dividing an integer by 2 and why?
23 Answers
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nginx showing blank PHP pages
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252
For reference, I am attaching my location block for catching files with the .php extension:
l...
SVN needs-lock 设置强制只读属性（官方资料） - 更多技术 - 清泛网 - 专注...
...available (Windows only):
@echo off
set REPOS=%1
set TRANSACTION=%2
set SVNLOOK="c:\Program Files\Subversion\apache2.2\bin\svnlook.exe"
set TEMP=c:\temp
if exist %TEMP%\tempfile%2 del %TEMP%\tempfile%2
for /f "tokens=1,2 usebackq" %%i in (`%SVNLOOK% changed -t %2 %1`) do @if %%i==...