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Test whether a list contains a specific value in Clojure
...been the most important function for collections. en.wikipedia.org/wiki/Set_(mathematics)#Membership
– jgomo3
Apr 3 '18 at 11:52
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Deleting DataFrame row in Pandas based on column value
...If I'm understanding correctly, it should be as simple as:
df = df[df.line_race != 0]
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docker error: /var/run/docker.sock: no such file or directory
... run the container.
I am on mac, installed boot2docker and have the DOCKER_HOST env set up.
11 Answers
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How to append rows to an R data frame
... near data.table + manual exponential growth. The difference is almost two orders of magnitude!
Summary
If you know that you will append rather small number of rows (n<=100), go ahead and use the simplest possible solution: just assign the rows to the data.frame using bracket notation and ignor...
Mac OS X Terminal: Map option+delete to “backward delete word”
...if you don't have checked use option as meta key)
meta+delete will treat / _ as word delimiter where ^W will consider space as delimiter.
e.g.
using ESC+Bakcspace on (cursor at the end)
rm /dira/dirb/file1
gives
rm /dira/dirb/
while ^W on the same will give
rm
So it is better to use \033\1...
How do I rename the extension for a bunch of files?
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This worked for me on OSX from .txt to .txt_bak
find . -name '*.txt' -exec sh -c 'mv "$0" "${0%.txt}.txt_bak"' {} \;
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Extract a dplyr tbl column as a vector
...ge:base':
#>
#> intersect, setdiff, setequal, union
db <- src_sqlite(tempfile(), create = TRUE)
iris2 <- copy_to(db, iris)
vec <- pull(iris2, Species)
head(vec)
#> [1] "setosa" "setosa" "setosa" "setosa" "setosa" "setosa"
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Android SDK on a 64-bit linux machine
...s. Your solution worked for my Linux Mint 13.
– pavel_kazlou
Sep 20 '12 at 20:55
Agree with commenter above, ubuntu 12...
rails + MySQL on OSX: Library not loaded: libmysqlclient.18.dylib
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The solution is pretty easy; Add the library path in your ~/.bash_profile or ~/.profile file:
MYSQL=/usr/local/mysql/bin
export PATH=$PATH:$MYSQL
export DYLD_LIBRARY_PATH=/usr/local/mysql/lib:$DYLD_LIBRARY_PATH
If it is still not working (this work for me):
sudo ln -s /usr/local/mysql/...
Ruby - test for array
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You probably want to use kind_of().
>> s = "something"
=> "something"
>> s.kind_of?(Array)
=> false
>> s = ["something", "else"]
=> ["something", "else"]
>> s.kind_of?(Array)
=> true
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