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Why were pandas merges in python faster than data.table merges in R in 2012?
I recently came across the pandas library for python, which according to this benchmark performs very fast in-memory merges. It's even faster than the data.table package in R (my language of choice for analysis).
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what is the difference between 'transform' and 'fit_transform' in sklearn
In the sklearn-python toolbox, there are two functions transform and fit_transform about sklearn.decomposition.RandomizedPCA . The description of two functions are as follows
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How to grant remote access permissions to mysql server for user?
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I executed the command in mysql, but SHOW GRANTS still shows the same (as in my question). I even did FLUSH PRIVILGES. Is there something I miss?
– Aufwind
Jun 4 '11 at 20:33
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MySQL, Check if a column exists in a table with SQL
... query that will check if a specific table in MySQL has a specific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Check image width and height before upload with Javascript
...ke it you realize this is only supported in a few browsers. Mostly firefox and chrome, could be opera as well by now.
P.S. The URL.createObjectURL() method has been removed from the MediaStream interface. This method has been deprecated in 2013 and superseded by assigning streams to HTMLMediaElemen...
In Python, what is the difference between “.append()” and “+= []”?
...d will add one item to the list, while += will copy all elements of right-hand-side list into the left-hand-side list.
Update: perf analysis
Comparing bytecodes we can assume that append version wastes cycles in LOAD_ATTR + CALL_FUNCTION, and += version -- in BUILD_LIST. Apparently BUILD_LIST outw...
Cross-browser custom styling for file upload button [duplicate]
...visibility:hidden or display:none file-input). I've tested in emulated IE7 and up, and it worked perfectly.
You can't use <button>s inside <label> tags unfortunately, so you'll have to define the styles for the buttons yourself. To me, this is the only downside to this approach.
If t...
Default value to a parameter while passing by reference in C++
...ifferent address to the function? or will the address of State be always 0 and so meaningless?
– Sony
Jun 29 '09 at 18:10
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Difference between toFixed() and toPrecision()?
I'm new to JavaScript and just discovered toFixed() and toPrecision() to round numbers. However, I can't figure out what the difference between the two is.
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Bash script to calculate time elapsed
...a script in bash to calculate the time elapsed for the execution of my commands, consider:
10 Answers
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