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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 = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a)...
How to connect to Mysql Server inside VirtualBox Vagrant?
... can I connect to that server outside the vm? I already forward the port 3306 of the Vagrantfile , but when I try to connect to the mysql server, it`s resposts with the error:
'reading initial communication packet'
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How to convert ASCII code (0-255) to its corresponding character?
How can I convert, in Java, the ASCII code (which is an integer from [0, 255] range) to its corresponding ASCII character?
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How to change colors of a Drawable in Android?
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I think you can actually just use Drawable.setColorFilter( 0xffff0000, Mode.MULTIPLY ). This would set white pixels to red but I don't think it would affect the transparent pixels.
See Drawable#setColorFilter
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How to overcome TypeError: unhashable type: 'list'
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As indicated by the other answers, the error is to due to k = list[0:j], where your key is converted to a list. One thing you could try is reworking your code to take advantage of the split function:
# Using with ensures that the file is properly closed when you're done
with open('filename....
Possible reasons for timeout when trying to access EC2 instance
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edited May 12 '10 at 6:00
answered May 11 '10 at 19:55
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add a string prefix to each value in a string column using Pandas
...['col'].astype(str)
Example:
>>> df = pd.DataFrame({'col':['a',0]})
>>> df
col
0 a
1 0
>>> df['col'] = 'str' + df['col'].astype(str)
>>> df
col
0 stra
1 str0
share
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ActiveRecord: size vs count
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edited Jul 10 '12 at 22:15
Jo Liss
22.5k1414 gold badges101101 silver badges150150 bronze badges
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How to change line width in ggplot?
... theme(axis.text.x = element_text(
colour = 'black', angle = 90, size = 13,
hjust = 0.5, vjust = 0.5),axis.title.x=element_blank()) +
ylab("FSI (%Change)") +
theme(axis.text.y = element_text(colour = 'black', size = 12),
axis.title.y = element_text(size = 12...
Catching error codes in a shell pipe
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20
If you really don't want the second command to proceed until the first is known to be successful...