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How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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Get key by value in dictionary
I made a function which will look up ages in a Dictionary and show the matching name:
34 Answers
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ggplot with 2 y axes on each side and different scales
I need to plot a bar chart showing counts and a line chart showing rate all in one chart, I can do both of them separately, but when I put them together, I scale of the first layer (i.e. the geom_bar ) is overlapped by the second layer (i.e. the geom_line ).
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Determining if a number is either a multiple of ten or within a particular set of ranges
...m - 1) / 10) % 2 == 1 && num <= 100)
But that's rather dense, and you might be better off just listing the options explicitly.
Now that you've given a better idea of what you are doing, I'd write the second one as:
int getRow(int num) {
return (num - 1) / 10;
}
if (ge...
Elegant way to check for missing packages and install them?
...de with coauthors these days. Many of them are novice/intermediate R users and don't realize that they have to install packages they don't already have.
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XMLHttpRequest cannot load file. Cross origin requests are only supported for HTTP
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If you are doing something like writing HTML and Javascript in a code editor on your personal computer, and testing the output in your browser, you will probably get error messages about Cross Origin Requests. Your browser will render HTML and run Javascript, jQuery, a...
Can't connect Nexus 4 to adb: unauthorized
I have a Nexus 4 with Android 4.3 and I am trying to connect the device to a computer with Windows 7 64bit.
26 Answers
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How to make a flat list out of list of lists?
...for item in sublist]
As evidence, you can use the timeit module in the standard library:
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
10000 loops, best of 3: 143 usec per loop
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l...
What is the idiomatic Go equivalent of C's ternary operator?
In C/C++ (and many languages of that family), a common idiom to declare and initialize a variable depending on a condition uses the ternary conditional operator :
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How to update Python?
... 2012. I can't find any consensus on whether I should completely uninstall and wipe this version before putting on the latest version.
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