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What is the “->” PHP operator called and how do you say it when reading code out loud? [closed]
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16 Answers
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Batch file to copy directories recursively
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179
Look into xcopy, which will recursively copy files and subdirectories.
There are examples, 2/...
Copy all files with a certain extension from all subdirectories
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179
--parents is copying the directory structure, so you should get rid of that.
The way you've w...
Inserting a Link to a Webpage in an IPython Notebook
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172
For visual learners.
[blue_text](url_here)
Thanks dbliss.
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Is Hash Rocket deprecated?
...e stating the Hash Rocket form is actually deprecated/unadvised as of Ruby 1.9.
1 Answer
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How to remove specific element from an array using python
...still don't need to iterate over. Just do:
index = initial_list.index(item1)
del initial_list[index]
del other_list[index]
share
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follow
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Primary key/foreign Key naming convention [closed]
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13 Answers
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How do I enable/disable log levels in Android?
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17 Answers
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Drop data frame columns by name
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You can use a simple list of names :
DF <- data.frame(
x=1:10,
y=10:1,
z=rep(5,10),
a=11:20
)
drops <- c("x","z")
DF[ , !(names(DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT ...