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Python Pandas merge only certain columns
Is it possible to only merge some columns? I have a DataFrame df1 with columns x, y, z, and df2 with columns x, a ,b, c, d, e, f, etc.
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How do I remove documents using Node.js Mongoose?
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If you don't feel like iterating, try FBFriendModel.find({ id:333 }).remove( callback ); or FBFriendModel.find({ id:333 }).remove().exec();
mongoose.model.find returns a Query, which has a remove function.
Update for Mongoose v5.5.3 - remove() is...
How to create a custom-shaped bitmap marker with Android map API v2 [duplicate]
...re I'm using Google Map API v2. I need to show the user location on a map with custom markers.
4 Answers
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How to get RelativeLayout working with merge and include?
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There is an issue with the include tag. Check: https://issuetracker.google.com/issues/36908001
To fix it, make sure you overwrite BOTH layout_width and layout_height when including, otherwise everything will be ignored.
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Using multiple delimiters in awk
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The delimiter can be a regular expression.
awk -F'[/=]' '{print $3 "\t" $5 "\t" $8}' file
Produces:
tc0001 tomcat7.1 demo.example.com
tc0001 tomcat7.2 quest.example.com
tc0001 tomcat7.5 www.example.com
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Node.js: printing to console without a trailing newline?
Is there a method for printing to the console without a trailing newline? The console object documentation doesn't say anything regarding that:
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Why are function pointers and data pointers incompatible in C/C++?
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An architecture doesn't have to store code and data in the same memory. With a Harvard architecture, code and data are stored in completely different memory. Most architectures are Von Neumann architectures with code and data in the...
How do I shuffle an array in Swift?
How do I randomize or shuffle the elements within an array in Swift? For example, if my array consists of 52 playing cards, I want to shuffle the array in order to shuffle the deck.
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Select first row in each GROUP BY group?
As the title suggests, I'd like to select the first row of each set of rows grouped with a GROUP BY .
17 Answers
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Using switch statement with a range of value in each case?
In Java, is it possible to write a switch statement where each case contains more than one value? For example (though clearly the following code won't work):
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