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&& (AND) and || (OR) in IF statements
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No, it will not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other way around
if (str == null || str.isEmpty())...
Repeat each row of data.frame the number of times specified in a column
What is the simplest way to expand each row the first two columns of the data.frame above, so that each row is repeated the number of times specified in the column 'freq'?
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Working with huge files in VIM
... up all my memory and then printed an error message :-(. I could not use hexedit for either, as it cannot insert anything, just overwrite. Here is an alternative approach:
You split the file, edit the parts and then recombine it. You still need twice the disk space though.
Grep for something surr...
Renaming files in a folder to sequential numbers
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let a=a+1
done
using the -i flag prevents automatically overwriting existing files.
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Attempted to read or write protected memory. This is often an indication that other memory is corrup
...DLL. Turns out, the problem was that I changed the Platform for Build from x86 to Any CPU and that was enough to trigger this error. Changing it back to x86 did the trick. Might help someone.
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Add line break to 'git commit -m' from the command line
... or stdout. With the here document, the git command can read the message text from stdin, and the -F option gives the file name to read the message from.
– Simon Richter
Sep 20 '18 at 23:22
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How to set cornerRadius for only top-left and top-right corner of a UIView?
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If you don't do that it won't show up.
And to round corners, use the extension:
extension UIView {
func roundCorners(corners: UIRectCorner, radius: CGFloat) {
let path = UIBezierPath(roundedRect: bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))...
Django : How can I see a list of urlpatterns?
... a list of all the urls in your project, first you need to install django-extensions, add it to your settings like this:
INSTALLED_APPS = (
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'django_extensions',
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)
And then, run this command in your terminal
./manage.py show_urls
For more information you can check the documentation.
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Failed to Attach to Process ID Xcode
Anyone has experienced this problem?
Yesterday I still can run my app in simulator but now I cannot run my app since Xcode prints this error in console:
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How to measure time taken between lines of code in python?
So in Java, we can do How to measure time taken by a function to execute
7 Answers
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