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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
How to modify a global variable within a function in bash?
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When you use a command substitution (ie the $(...) construct), you are creating a subshell. Subshells inherit variables from their parent shells, but this only works one way - a subshell cannot modify the environment of its parent shell. Your v...
How to implement an ordered, default dict? [duplicate]
I would like to combine OrderedDict() and defaultdict() from collections in one object, which shall be an ordered, default dict .
Is this possible?
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Using Chrome's Element Inspector in Print Preview Mode?
I am working on developing a website and need to work on the print view. Typically when I have layout issues I use Chrome's Element Inspector. However this does not exist in print preview mode.
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Unix command to find lines common in two files
I'm sure I once found a unix command which could print the common lines from two or more files, does anyone know its name? It was much simpler than diff .
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Need to list all triggers in SQL Server database with table name and table's schema
I need to list all triggers in SQL Server database with table name and table's schema.
19 Answers
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How do I list all files of a directory?
How can I list all files of a directory in Python and add them to a list ?
21 Answers
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is it possible to change values of the array when doing foreach in javascript?
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The callback is passed the element, the index, and the array itself.
arr.forEach(function(part, index, theArray) {
theArray[index] = "hello world";
});
edit — as noted in a comment, the .forEach() function can take a second argument, which will be used as the value...
Is there a foreach loop in Go?
...h entry it assigns iteration values to corresponding iteration
variables and then executes the block.
As an example:
for index, element := range someSlice {
// index is the index where we are
// element is the element from someSlice for where we are
}
If you don't care about the index...
How do I remove msysgit's right click menu options?
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64-Bit Windows
From a cmd.exe window, run these commands:
cd "C:\Program Files (x86)\Git\git-cheetah"
regsvr32 /u git_shell_ext64.dll
32-Bit Windows
From a cmd.exe window, run these commands
cd "C:\Program Files\Git\git-cheetah"
regsvr32 /u git_shell_ext.dll
Windows 1...