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Extract a dplyr tbl column as a vector
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188
With dplyr 0.7.0, you can use pull to get a vector from a tbl.
library("dplyr")
#>
#&g...
How to extract numbers from a string in Python?
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17 Answers
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Detect if a NumPy array contains at least one non-numeric value?
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187
This should be faster than iterating and will work regardless of shape.
numpy.isnan(myarray)....
Does Python have a ternary conditional operator?
...ession:
>>> pass if False else x = 3
File "<stdin>", line 1
pass if False else x = 3
^
SyntaxError: invalid syntax
You can, however, use conditional expressions to assign a variable like so:
x = a if True else b
Think of the conditional expression as switching betwee...
How do I get a UTC Timestamp in JavaScript?
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16 Answers
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dplyr: “Error in n(): function should not be called directly”
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120
I presume you have dplyr and plyr loaded in the same session. dplyr is not plyr. ddply is not ...
How to reload apache configuration for a site without restarting apache
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187
should be possible using the command
sudo /etc/init.d/apache2 reload
hope that helps
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CASCADE DELETE just once
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No. To do it just once you would simply write the delete statement for the table you want to ...
IE7 does not understand display: inline-block
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301
The IE7 display: inline-block; hack is as follows:
display: inline-block;
*display: inline;
zoo...