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Truncate number to two decimal places without rounding
Suppose I have a value of 15.7784514, I want to display it 15.77 with no rounding.
36 Answers
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Call apply-like function on each row of dataframe with multiple arguments from each row
...y to a subset of the original data.
dat <- data.frame(x=c(1,2), y=c(3,4), z=c(5,6))
apply(dat[,c('x','z')], 1, function(x) sum(x) )
or if your function is just sum use the vectorized version:
rowSums(dat[,c('x','z')])
[1] 6 8
If you want to use testFunc
testFunc <- function(a, b) a +...
Count number of days between two dates
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Andrew FranceAndrew France
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How to reset or change the MySQL root password?
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34 Answers
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“Unable to find remote helper for 'https'” during git clone
...=devel
If you are running Ubuntu instead:
sudo apt-get install libcurl4-openssl-dev
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Razor View throwing “The name 'model' does not exist in the current context”
After significant refactoring in my MVC 4 application, and Razor shows this error while debugging Views:
22 Answers
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Conversion of System.Array to List
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440
Save yourself some pain...
using System.Linq;
int[] ints = new [] { 10, 20, 10, 34, 113 };
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Eclipse: Referencing log4j.dtd in log4j.xml
I've been using log4j for quite a while now and I usually use this at the top of the log4j.xml (probably just like many others and according to Google this is the way to do it):
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Is there a difference between using a dict literal and a dict constructor?
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answered Jul 7 '11 at 12:43
John La RooyJohn La Rooy
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How to align absolutely positioned element to center?
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If you set both left and right to zero, and left and right margins to auto you can center an abs...