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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = dat...
How to remove item from list in C#?
... use Remove(T item):
var itemToRemove = resultlist.Single(r => r.Id == 2);
resultList.Remove(itemToRemove);
When you are not sure the item really exists you can use SingleOrDefault. SingleOrDefault will return null if there is no item (Single will throw an exception when it can't find the item...
ArithmeticException: “Non-terminating decimal expansion; no exact representable decimal result”
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862
From the Java 11 BigDecimal docs:
When a MathContext object is supplied with a precision settin...
How to store standard error in a variable
...d output.
ERROR=$( { ./useless.sh | sed s/Output/Useless/ > outfile; } 2>&1 )
Note that the semi-colon is needed (in classic shells - Bourne, Korn - for sure; probably in Bash too). The '{}' does I/O redirection over the enclosed commands. As written, it would capture errors from sed ...
Scala how can I count the number of occurrences in a list
I want to implement it like this: list.count(2) (returns 3).
16 Answers
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How to subtract 2 hours from user's local time?
...e JavaScript code block that will allow me to display the local time minus 2 hours?
2 Answers
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Regular expression to match any character being repeated more than 10 times
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edited Jun 22 '16 at 17:52
Wiktor Stribiżew
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Find row where values for column is maximal in a pandas DataFrame
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252
Use the pandas idxmax function. It's straightforward:
>>> import pandas
>>>...
What is a plain English explanation of “Big O” notation?
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