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Split comma-separated strings in a column into separate rows
...odified according to Rich Scriven's comment,
Jaap's two data.table methods and two dplyr / tidyr approaches,
Ananda's splitstackshapesolution,
and two additional variants of Jaap's data.table methods.
Overall 8 different methods were benchmarked on 6 different sizes of data frames using the micro...
How to check if an element is in an array
...y? Xcode does not have any suggestions for contain , include , or has , and a quick search through the book turned up nothing. Any idea how to check for this? I know that there is a method find that returns the index number, but is there a method that returns a boolean like ruby's #include? ?
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How to drive C#, C++ or Java compiler to compute 1+2+3+…+1000 at compile time?
...ing compiler features. This means that I am not allowed to write a program and execute it, but I should just write a program that could drive the compiler to compute this sum while compilation and print the result when compilation completes. As a hint, he told me that I may use generics and pre-proc...
How does @synchronized lock/unlock in Objective-C?
Does @synchronized not use "lock" and "unlock" to achieve mutual exclusion? How does it do lock/unlock then?
5 Answers
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Counting the occurrences / frequency of array elements
In Javascript, I'm trying to take an initial array of number values and count the elements inside it. Ideally, the result would be two new arrays, the first specifying each unique element, and the second containing the number of times each element occurs. However, I'm open to suggestions on the form...
git: difference between “branchname” and “refs/heads/branchname”
Best to be explained at an example: I am on branch 0.58 of repository and this his how I pull:
3 Answers
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Get the last non-empty cell in a column in Google Sheets
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Slightly simplified answer that also handles blanks, by Doug Bradshaw: =INDEX(FILTER(A1:A,NOT(ISBLANK(A1:A))),COUNTA(A1:A)) (can change starting row A1) full description at: stackoverflow.com/a/27623407/539149
– Zack Morris
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IntelliJ IDEA 13 uses Java 1.5 despite setting to 1.7
...ng can be added in default maven projects. Use Preferences | Editor | File and Code Templates | Maven | Maven Projects.xml <properties> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> </proper...
What does “zend_mm_heap corrupted” mean
...on that I've never had before. I decided to check the Apache's error log, and I found an error message saying "zend_mm_heap corrupted". What does this mean.
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How can I save a screenshot directly to a file in Windows? [closed]
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You can code something pretty simple that will hook the PrintScreen and save the capture in a file.
Here is something to start to capture and save to a file. You will just need to hook the key "Print screen".
using System;
using System.Drawing;
using System.IO;
using System.Drawing.Imaging;...
