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How to join (merge) data frames (inner, outer, left, right)
...nner join: merge(df1, df2) will work for these examples because R automatically joins the frames by common variable names, but you would most likely want to specify merge(df1, df2, by = "CustomerId") to make sure that you were matching on only the fields you desired. You can also use the by.x and b...
How can I get all constants of a type by reflection?
How can I get all constants of any type using reflection?
4 Answers
4
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An efficient compression algorithm for short text strings [closed]
I'm searching for an algorithm to compress small text strings: 50-1000 bytes (i.e. URLs). Which algorithm works best for this?
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C state-machine design [closed]
I am crafting a small project in mixed C and C++. I am building one small-ish state-machine at the heart of one of my worker thread.
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Capybara Ambiguity Resolution
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Specifically, Capybara 2.0 has intelligent waiting logic to ensure specs pass or fail consistently across machines of differing processing speeds while only waiting the minimum necessary time. Using first as suggested above, unless y...
Where can I locate themes for VS2012
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New Theme editor Specifically for 2012:
http://visualstudiogallery.msdn.microsoft.com/366ad100-0003-4c9a-81a8-337d4e7ace05
Comes w/ VS 2010 style blue and a few others...
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How can I find all of the distinct file extensions in a folder hierarchy?
...inux machine I would like to traverse a folder hierarchy and get a list of all of the distinct file extensions within it.
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Find all tables containing column with specified name - MS SQL Server
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Not surprising it works on all those different databases given that INFORMATION_SCHEMA is part of the ANSI Standard
– Davos
May 24 '18 at 4:42
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What are the use cases for selecting CHAR over VARCHAR in SQL?
I realize that CHAR is recommended if all my values are fixed-width. But, so what? Why not just pick VARCHAR for all text fields just to be safe.
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How to print a dictionary's key?
...no "the key". You have the keys() method, which gives you a python list of all the keys, and you have the iteritems() method, which returns key-value pairs, so
for key, value in mydic.iteritems() :
print key, value
Python 3 version:
for key, value in mydic.items() :
print (key, value)
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