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Remove columns from dataframe where ALL values are NA
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dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
&g...
Skip first entry in for loop in python?
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# do work on 'prev' not 'car'
# at end of loop:
prev = car
# now you can do whatever you want to do to the last one on 'prev'
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What is the optimal algorithm for the game 2048?
...code with emscripten to javascript, and it works quite well in the browser now! Cool to watch, without the need to compile and everything... In Firefox, performance is quite good...
– reverse_engineer
Aug 23 '14 at 17:11
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Why do I get a SyntaxError for a Unicode escape in my file path?
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why triple `\`? Editing typo? Ok now I see post history and someone fixed formatting not carefully enough, so I've fixed that. Please familiarize yourself it with SO features.
– Marek R
Jan 20 at 11:17
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Node package ( Grunt ) installed but not available
... grunt-cli ).
You can establish that's working by typing grunt --version
Now you can install the current version of Grunt local to your project. So from your project's location...
npm install grunt --save-dev
The save-dev switch isn't strictly necessary but is a good idea because it will mark g...
How can I add a help method to a shell script?
... shift
break
;;
-*)
echo "Error: Unknown option: $1" >&2
## or call function display_help
exit 1
;;
*) # No more options
break
;;
esac
done
######################
# Check if parameter #
# is...
How to inflate one view with a layout
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Just tried this now, I needed: View child = getLayoutInflater().inflate(R.layout.child,null);
– James
May 24 '12 at 0:23
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Difference between two dates in MySQL
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SELECT TIMESTAMPDIFF(HOUR,NOW(),'2013-05-15 10:23:23')
calculates difference in hour.(for days--> you have to define day replacing hour
SELECT DATEDIFF('2012-2-2','2012-2-1')
SELECT TO_DAYS ('2012-2-2')-TO_DAYS('2012-2-1')
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How to set TextView textStyle such as bold, italic
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TextView text = (TextView)findViewById(R.id.THE_TEXTVIEW_ID);
now set the textview properties..
text.setTypeface(null, Typeface.BOLD); //-- for only bold the text
text.setTypeface(null, Typeface.BOLD_ITALIC); //-- for bold & italic the text
text.setTypeface(null, Typeface.ITALIC...
Is there a label/goto in Python?
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Granted, that isn't the best way to substitute for goto. But without knowing exactly what you're trying to do with the goto, it's hard to give specific advice.
@ascobol:
Your best bet is to either enclose it in a function or use an exception. For the function:
def loopfunc():
while 1:
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