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Replace a value in a data frame based on a conditional (`if`) statement
In the R data frame coded for below, I would like to replace all of the times that B
appears with b .
8 Answers
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How do I remove javascript validation from my eclipse project?
...urned on Javascript support. Now eclipse complains that JQuery library has errors in it and is not letting me compile the project. Does anyone know how to turn javascript validation off?
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Callback functions in C++
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There is an error in the class method example. The Invocation should be: (instance.*callback)(1.0f)
– CarlJohnson
Sep 24 '12 at 22:15
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How do I launch the Android emulator from the command line?
...t I'm looking for. When I run adb install <path-to-your-APK>, I get error: device not found. If I run the emulator in one shell and the adb install command in another, I get error: device offline. How do I set an emulated virtual device?
– Thierry Lam
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Which is preferred: Nullable.HasValue or Nullable != null?
...uming SomeNullable is an int?).
While SomeNullable.Value gets us a runtime error if we assigned null to SomeNullable. This is in fact the only case where nullables could cause us a problem, thanks to a combination of overloaded operators, overloaded object.Equals(obj) method, and compiler optimizati...
Fastest way to tell if two files have the same contents in Unix/Linux?
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Why don't you get the hash of both files content?
Try this script, call it for example script.sh and then run it as follows: script.sh file1.txt file2.txt
#!/bin/bash
file1=`md5 $1`
file2=`md5 $2`
if [ "$file1" = "$file2" ]
then
echo "Files have the same content"
else
echo "Files h...
Is there a way to cache GitHub credentials for pushing commits?
...trc does not work outside of a git repository. It fails with the following error:
fatal: Not a git repository: . at /usr/share/perl5/Git.pm line 214.
There is no real reason why need to be within a repository, though. Credential helpers should be able to work just fine outside the repository ...
Numpy first occurrence of value greater than existing value
... about why it gives the correct result despite the original intent not actually seeking a maximum, not why it is faster as I cannot claim to understand the inner details of argmax.
– askewchan
Oct 8 '14 at 14:24
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What is the curiously recurring template pattern (CRTP)?
...e. If you want to see the corner case anyway even though it does not cause error see here: ideone.com/LPkktf
– odinthenerd
Dec 6 '13 at 9:01
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How do I create directory if none exists using File class in Ruby?
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@JosephK - for me this (misleading) EEXIST error ended up being a permission issue.
– TomG
Dec 17 '19 at 13:19
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