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Dynamically select data frame columns using $ and a character value
...alise that $, like everything else in R, (including for instance ( , + , ^ etc) is a function, that takes arguments and is evaluated. df$V1 could be rewritten as
`$`(df , V1)
or indeed
`$`(df , "V1")
But...
`$`(df , paste0("V1") )
...for instance will never work, nor will anything else that...
How to upload a file in Django? [closed]
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Phew, Django documentation really does not have good example about this. I spent over 2 hours to dig up all the pieces to understand how this works. With that knowledge I implemented a project that makes possible to upload files and show them as list. To...
Mismatched anonymous define() module
I'm getting this error when I browse my webapp for the first time (usually in a browser with disabled cache).
7 Answers
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unit testing of private functions with mocha and node.js
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If the function is not exported by the module, it cannot be called by test code outside the module. That's due to how JavaScript works, and Mocha cannot by itself circumvent this.
In the few instances where I determined that testing a private function is the right thing to do, what I'...
Add spaces before Capital Letters
... (I even voted up Martin Browns answer), but they are expensive (and personally I find any pattern longer than a couple of characters prohibitively obtuse)
This function
string AddSpacesToSentence(string text, bool preserveAcronyms)
{
if (string.IsNullOrWhiteSpace(text))
return...
How to list branches that contain a given commit?
...uery git to find out which branches contain a given commit? gitk will usually list the branches, unless there are too many, in which case it just says "many (38)" or something like that. I need to know the full list, or at least whether certain branches contain the commit.
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In C#, should I use string.Empty or String.Empty or “” to intitialize a string?
...person - so I suggest you find out what most people on your team like, and all go with that for consistency. Personally I find "" easier to read.
The argument that "" and " " are easily mistaken for each other doesn't really wash with me. Unless you're using a proportional font (and I haven't worke...
Removing all non-numeric characters from string in Python
How do we remove all non-numeric characters from a string in Python?
7 Answers
7
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Importing a CSV file into a sqlite3 database table using Python
...lumn headers in the csv file. And close the connection to the database by calling con.close() at the end.
– Jonas
Aug 8 '16 at 21:31
1
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How to create a zip archive of a directory in Python?
...e. The documentation tells you what functions are available, but doesn't really explain how you can use them to zip an entire directory. I think it's easiest to explain with some example code:
#!/usr/bin/env python
import os
import zipfile
def zipdir(path, ziph):
# ziph is zipfile handle
f...