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How to join (merge) data frames (inner, outer, left, right)
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This works in data.table now, same function just faster.
– marbel
Dec 2 '16 at 19:44
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sho...
Are typedef and #define the same in c?
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#define defines macros.
typedef defines types.
Now saying that, here are a few differences:
With #define you can define constants that can be used in compile time. The constants can be used with #ifdef to check how the code is compiled, and specialize certain code accord...
Install Node.js on Ubuntu
...do] apt-get update
node.js installation
[sudo] apt-get install nodejs
Now checking node.js version
node -v
Outputs
v0.10.20
This command should install npm.
npm install
Check npm version
npm -v
Outputs
1.4.3
If for some reason, if you see npm is not installed, you may try running...
how to make a specific text on TextView BOLD
I don't know how to make a specific text on TextView become BOLD.
23 Answers
23
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How can I prevent the backspace key from navigating back?
... with my debugger. My apologies for editing/breaking your code. I realize now that I overstepped my bounds (editing) forgive me. I am truly sorry and I meant no complaints to your wonderful solution to this problem. Again, my apologies. This code works well. I believe this is the best answer and ...
Pandas aggregate count distinct
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This answer is outdated. You can now use nunique directly. See @Blodwyn Pig's solution below
– Ted Petrou
Nov 5 '17 at 20:07
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Can you have multiline HTML5 placeholder text in a ?
...laceholder text in a textarea without stripping the newlines. Does anyone know what the name of the 'feature' is so that I can a) look for it, and b) test for it?
– Ben
Jul 2 '14 at 6:35
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How to migrate back from initial migration in Django 1.7?
I created a new app with some models and now I noticed that some of the models are poorly thought out. As I haven't committed the code the sensible thing would be to migrate the database to last good state and redo the migration with better models. In this case the last good state is database where ...
How to reference a file for variables using Bash?
... accomplish this.
Running export and echo $ENV should be all you need to know about accessing variables. Accessing environment variables is done the same way as a local variable.
To set them, say:
export variable=value
at the command line. All scripts will be able to access this value.
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How to delete a specific line in a file?
...ng along the line as it's read. Once that line has been read the cursor is now past it. When you try to write into the file you write where the cursor currently is. By re-opening the file you reset the cursor.
– Waddas
Aug 6 '14 at 20:48
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