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Python Pandas merge only certain columns
...umn 'Unique_External_Users' from df2 to df1 but got an error ... "None of [Index(['U', 'n', 'i', 'q', 'u', 'e', '', 'E', 'x', 't', 'e', 'r', 'n', 'a',\n 'l', '', 'U', 's', 'e', 'r', 's'],\n dtype='object')] are in the [columns]" .
– CoolDocMan
Feb 28...
Drop data frame columns by name
...eps]
EDIT :
For those still not acquainted with the drop argument of the indexing function, if you want to keep one column as a data frame, you do:
keeps <- "y"
DF[ , keeps, drop = FALSE]
drop=TRUE (or not mentioning it) will drop unnecessary dimensions, and hence return a vector with the va...
Ignore python multiple return value
...g to a variable and then not using it? The function is returning a tuple; index it like a tuple.
– endolith
Mar 26 '13 at 14:41
How to exit an if clause
...
Ideally you can achieve both, but there are times when you must trade good code for good performance. Those times are rare, especially when you are considering using Python. In other words: don't worry so much about function c...
Best practices with STDIN in Ruby?
...le that gets all input from named files or all from STDIN.
ARGF.each_with_index do |line, idx|
print ARGF.filename, ":", idx, ";", line
end
# print all the lines in every file passed via command line that contains login
ARGF.each do |line|
puts line if line =~ /login/
end
Thank goodness ...
Why are dates calculated from January 1st, 1970?
...1st, 1970) as default standard
The Question makes two false assumptions:
All time-tracking in computing is done as a count-since-1970.
Such tracking is standard.
Two Dozen Epochs
Time in computing is not always tracked from the beginning of 1970 UTC. While that epoch reference is popular, various...
How do I check if a string contains another string in Swift?
...ptions mask: NSStringCompareOptions = default, range searchRange: Range<Index>? = default, locale: NSLocale? = default) -> Range<Index>?
– newacct
Jul 11 '15 at 20:32
...
Ways to save Backbone.js model data?
...
Basically Models have a property called attributes which are the various values a certain model may have. Backbone uses JSON objects as a simple way to populate these values using various methods that take JSON objects. Example:
...
Array.push() if does not exist?
... It is better to extend Array prototype with JavaScript 1.6 method IndexOf instead of your inArray.
– Eugene Gluhotorenko
Jul 1 '13 at 8:16
7
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What is the documents directory (NSDocumentDirectory)?
...ForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) objectAtIndex:0]
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