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Python Create unix timestamp five minutes in the future
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answered May 5 '10 at 20:06
Daniel RhodenDaniel Rhoden
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Summarizing multiple columns with dplyr? [duplicate]
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#> 2 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
If you want to summarize only certain columns, use summarise_at or summarise_if functions.
Alternatively, the purrrlyr package provides the same functionality:
library(purrrlyr)
df %>% slice_rows("grp") %>% dmap(mea...
How to generate a create table script for an existing table in phpmyadmin?
... I wanted
– astrosixer
Jan 29 at 19:06
Are there arguments I can add to export it to a file?
– D...
Compiling Java 7 code via Maven
...reasing...
– Lucas
Nov 16 '14 at 19:06
@Lucas - just dont want to be responsible for people sticking to outdated versi...
TimeStamp on file name using PowerShell
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– Mark Schultheiss
Jul 11 '18 at 18:06
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How to see which flags -march=native will activate?
...taMark Lakata
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Tools for JPEG optimization? [closed]
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– Collin Anderson
Dec 13 '12 at 20:06
3
Progressive needs a lot more memory to decode. Regular j...
How do I format a date with Dart?
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answered Apr 21 '13 at 0:06
Seth LaddSeth Ladd
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
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answered Oct 22 '09 at 17:06
Arthur RonaldArthur Ronald
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Expand a random range from 1–5 to 1–7
...amental limit, then, is that we can do no better than log(7)/log(5) = 1.20906 calls to rand5() per call to rand7().
Side notes: all logarithms in this answer will be base 2 unless specified otherwise. rand5() will be assumed to return numbers in the range [0, 4], and rand7() will be assumed to ret...