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Aggregate / summarize multiple variables per group (e.g. sum, mean)
...('.*[0-9]')), sum)
# summarising a specific set of non-grouping variables based on condition (class)
df2 <- df1 %>% group_by(year, month) %>% summarise_if(is.numeric, sum)
The result of the latter two options:
year month x1 x2
<dbl> <dbl> <dbl>...
NUnit's Assert.Equals throws exception “Assert.Equals should not be used for assertions”
...ov Because that is impossible. You can't override a virtual method from a base class with a private one.
– Odrade
Jun 30 '15 at 21:01
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Missing XML comment for publicly visible type or member
... more understandable so you use a tool that generates documentation solely based on the method name and arguments types. Does it make sense to you? The user can see the name and types of the arguments, add comment to DateTime date- The date really doesn't help.
– gdoron is supp...
Check for internet connection availability in Swift
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As @Isuru said, this is based on stackoverflow.com/a/25623647/1187415, which has now been updated for Swift 2.
– Martin R
Jun 10 '15 at 1:52
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What is the intended use-case for git stash?
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I know StackOverflow is not the place for opinion based answers, but I actually have a good opinion on when to shelve changes with a stash.
You don't want to commit you experimental changes
When you make changes in your workspace/working tree, if you need to perform any br...
Get type name without full namespace
...imisation. It creates a new StringBuilder in each recursive call (even the base case when it's unused), yet ignores the string.Join temporary and LINQ lambda. Just use String until you know it's a bottleneck. /rant
– Nigel Touch
May 30 '18 at 19:08
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How to append one file to another in Linux from the shell?
...an just racing to submit something that was, in point of fact, incorrect. Based on the text of the question, I believe that cat file1 file2 > file3 is the appropriate command that @asir was looking for.
– dm78
Sep 2 '13 at 15:44
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I want to copy table contained from one database and insert onto another database table
...copy a table's schema as well as the data within that table to another database table in another database on a live server. How could I do this?
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handle textview link click in my android app
...l no" we can customise the LinkMovement method and handle clicks for words based on a pattern. Attached is the customised Link Movement Method.
public class CustomLinkMovementMethod extends LinkMovementMethod
{
private static Context movementContext;
private static CustomLinkMovementMethod linkMo...
pretty-print JSON using JavaScript
...ring, you had a normal object. JSON is always a string. It's just a string-based representation of a Javascript object.
– Clonkex
Jan 3 '18 at 2:53
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