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Selecting multiple columns in a pandas dataframe
I have data in different columns but I don't know how to extract it to save it in another variable.
18 Answers
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Signed to unsigned conversion in C - is it always safe?
...implementation-defined or an implementation-defined signal is raised.
Now we need to refer to (2) above. Your i will be converted to an unsigned value by adding UINT_MAX + 1. So the result will depend on how UINT_MAX is defined on your implementation. It will be large, but it will not overflow,...
Returning value from Thread
...;Integer>() {
@Override
public Integer call() {return 2;}
});
Now all you do is say value.get() whenever you need to grab your returned value, the thread is started the very second you give value a value so you don't ever have to say threadName.start() on it.
What a Future is, is a pro...
Why no generics in Go?
Disclaimer: I've only played with Go for one day now, so there's a good chance I've missed a lot.
6 Answers
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Padding between ActionBar's home icon and title
Does anybody know how to set padding between the ActionBar's home icon and the title?
21 Answers
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Why is MATLAB so fast in matrix multiplication?
...lementation of BLAS routines which were more and more efficient.
I don't know all the historical implementations (I was not born or a kid back then), but two of the most notable ones came out in the early 2000s: the Intel MKL and GotoBLAS. Your Matlab uses the Intel MKL, which is a very good, optim...
Java Timestamp - How can I create a Timestamp with the date 23/09/2007?
... as java.util.Date, java.util.Calendar, and java.text.SimpleDateFormat are now legacy, supplanted by the java.time classes built into Java 8 and later. See Tutorial by Oracle.
– Basil Bourque
Jan 24 '19 at 23:55
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How do I ignore files in a directory in Git?
...he .gitignore file. When one of the two mentioned git commands is executed now, the directory will be (unexpectedly) lost.
mkdir test
cd test
git init
echo "/localdata/*" >.gitignore
git add .gitignore
git commit -m "Add .gitignore."
mkdir localdata
echo "Important data" >localdata/important...
How do you create a Swift Date object?
...her date-times, you can use one of the following methods.
Method 1
If you know the number of seconds before or after the 2001 reference date, you can use that.
let someDateTime = Date(timeIntervalSinceReferenceDate: -123456789.0) // Feb 2, 1997, 10:26 AM
Method 2
Of course, it would be easier to us...
How to set Java environment path in Ubuntu
... java
java: /usr/bin/java /usr/share/java /usr/share/man/man1/java.1.gz
Now dig deeper-
$ ls -l /usr/bin/java
lrwxrwxrwx 1 root root 46 Aug 25 2018 /etc/alternatives/java -> /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java
Dig deeper:
$ ls -l /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java
...