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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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#> 8 virginica B 25
#> 9 virginica C 25
#> 10 empty_level A 0
#> 11 empty_level B 0
#> 12 empty_level C 0
Created on 2019-03-13 by the reprex package (v0.2.1)
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Strtotime() doesn't work with dd/mm/YYYY format
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Here is the simplified solution:
$date = '25/05/2010';
$date = str_replace('/', '-', $date);
echo date('Y-m-d', strtotime($date));
Result:
2010-05-25
The strtotime documentation reads:
Dates in the m/d/y or d-m-y formats are disambiguated by looking at the separator...
How to set an environment variable only for the duration of the script?
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10
1. How come PATH=$PATH:XYZ echo $PATH | grep XYZ doesn't have any output though? 2. What is the difference between using and not using env?...
How to find the largest file in a directory and its subdirectories?
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Quote from this link-
If you want to find and print the top 10 largest files names (not
directories) in a particular directory and its sub directories
$ find . -printf '%s %p\n'|sort -nr|head
To restrict the search to the present directory use "-maxdepth 1" with
find.
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In javascript, is an empty string always false as a boolean?
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edited Feb 10 '14 at 20:38
Charles Burns
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Effects of changing Django's SECRET_KEY
... looks like Django added the get_random_secret_key() function in version 1.10. You could use that to generate a new secret key.
$ ./manage.py shell -c "from django.core.management.utils import get_random_secret_key; print(get_random_secret_key())"
s!)5@5s79sp=92a+!f4v!1g0d0+64ln3d$xm1f_7=749ht&-...
JQuery to load Javascript file dynamically
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Dreen
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answered May 26 '09 at 20:54
Paolo BergantinoPao...
What is process.env.PORT in Node.js?
...v.PORT which equals to 4444 in this example. Run with sudo for ports below 1024.
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Git submodule push
...thub repo :)
– NiKo
Jan 7 '12 at 15:10
I don't understand how can you cd your_submodule before add your_submodule ? I ...
Custom error pages on asp.net MVC3
...gard.
– Darin Dimitrov
Oct 7 '13 at 10:29
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