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Group by multiple columns in dplyr, using string vector input
...C 0.20858897
7 C A 0.19502221
8 C B 0.56837548
9 C C -0.22682998
Note that since dplyr::summarize only strips off one layer of grouping at a time, you'...
How do I lowercase a string in Python?
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answered Jul 23 '15 at 22:40
Aaron Hall♦Aaron Hall
259k6969 gold badges353353 silver badges303303 bronze badges
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Does Typescript support the ?. operator? (And, what's it called?)
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edited Jan 4 at 22:11
answered Feb 12 '15 at 4:53
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setTimeout in for-loop does not print consecutive values [duplicate]
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answered Oct 22 '13 at 9:42
Mevin BabuMevin Babu
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How to calculate the angle between a line and the horizontal axis?
... function:
angleInDegrees = atan2(deltaY, deltaX) * 180 / PI
EDIT (Feb. 22, 2017): In general, however, calling atan2(deltaY,deltaX) just to get the proper angle for cos and sin may be inelegant. In those cases, you can often do the following instead:
Treat (deltaX, deltaY) as a vector.
Normali...
How do you use String.substringWithRange? (or, how do Ranges work in Swift?)
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matt---
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answered Jun 4 '14 at 18:42
ConnorConnor
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What is the difference between int, Int16, Int32 and Int64?
... +32,767)
Int32 -- (-2,147,483,648 to +2,147,483,647)
Int64 -- (-9,223,372,036,854,775,808 to +9,223,372,036,854,775,807)
As stated by James Sutherland in his answer:
int and Int32 are indeed synonymous; int will be a little more
familiar looking, Int32 makes the 32-bitness more expl...
Are static variables shared between threads?
...on.
– Jed Wesley-Smith
Feb 8 '11 at 22:24
2
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What does the 'b' character do in front of a string literal?
...hello world'
– Eli
Aug 21 '17 at 11:22
15
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Abstract classes in Swift Language
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Calvin Chen
322 bronze badges
answered Jun 8 '14 at 20:28
drewagdrewag
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