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Ruby: How to get the first character of a string
...ot that you should be using 1.8 anymore anyway!--but when this answer was posted it was still quite common):
puts 'Smith'[0] # prints 83
Of course, if you're not doing it on a regular basis, then defining the method might be overkill, and you could just do it directly:
puts last_name[0...
iPhone/iOS JSON parsing tutorial [closed]
...hing would be nice if it built. Fails for me with 44 errors in Xcode 4 in OS X Lion.
– Sarah Vessels
Jul 20 '12 at 17:04
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Javascript - How to extract filename from a file input control
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vog's answer is really close to the 100% accurate answer to the question (except needs to strip the extension.) A filename is no different from any other string.
– Jon Watte
May 21 '16 at 19:38
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Pass a data.frame column name to a function
...e more about tidyeval here.
library(rlang)
library(tidyverse)
set.seed(123)
df <- data.frame(B = rnorm(10), D = rnorm(10))
Use column names as strings
fun3 <- function(x, ...) {
# capture strings and create variables
dots <- ensyms(...)
# unquote to evaluate inside dplyr verbs
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Get the date (a day before current time) in Bash
... answered Nov 10 '09 at 10:17
ghostdog74ghostdog74
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ImportError: numpy.core.multiarray failed to import
...ommand and find it on your computer. I'm sure you can rm the directory on OSX via terminal, but I did it manually and it solved my issue.
– alexfigtree
Jan 18 '16 at 21:29
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What exactly does the .join() method do?
...t array.array('c', random.sample(string.ascii_letters, 20 - len(strid)))
.tostring() + strid
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How do I load a file into the python console?
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if the file contains import statements e.g. import os, does exec() execute those statements? I'm trying this currently and the answer appears to be no...
– Rylan Schaeffer
May 21 at 17:23
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Error when trying vagrant up
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If you're using OS X and used the standard install, Delete vagrant's old curl and it should now work
sudo rm /opt/vagrant/embedded/bin/curl
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How do I properly clean up Excel interop objects?
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Marshal.ReleaseComObject(sheets);
Marshal.ReleaseComObject(sheet);
POST MORTEM UPDATE:
I want every reader to read this answer by Hans Passant very carefully as it explains the trap I and lots of other developers stumbled into. When I wrote this answer years ago I didn't know about the effec...