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Extracting specific columns from a data frame
I have an R data frame with 6 columns, and I want to create a new dataframe that only has three of the columns.
10 Answers
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How to find duplicates in 2 columns not 1
I have a MySQL database table with two columns that interest me. Individually they can each have duplicates, but they should never have a duplicate of BOTH of them having the same value.
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Controlling mouse with Python
How does one control the mouse cursor in Python, i.e. move it to certain position and click, under Windows?
14 Answers
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C/C++ Struct vs Class
After finishing my C++ class it seemed to me the structs/classes are virtually identical except with a few minor differences.
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round() for float in C++
I need a simple floating point rounding function, thus:
22 Answers
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Detect URLs in text with JavaScript
Does anyone have suggestions for detecting URLs in a set of strings?
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How do you test a public/private DSA keypair?
...hat a given private key matches a given public key? I have a few *.pub and a few *.key files, and I need to check which go with which.
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How to get the path of the batch script in Windows?
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to drawRect or not to drawRect (when should one use drawRect/Core Graphics vs subviews/images and wh
To clarify the purpose of this question: I know HOW to create complicated views with both subviews and using drawRect. I'm trying to fully understand the when's and why's to use one over the other.
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in iPhone App How to detect the screen resolution of the device
In iPhone App,
while running the App on device How to detect the screen resolution of the device on which App is running?
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