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Fastest way to replace NAs in a large data.table
...m.time(a_gdata = f_gdata(dt1))
user system elapsed
18.805 12.301 134.985
system.time(a_andrie = f_andrie(dt1))
Error: cannot allocate vector of size 305.2 Mb
Timing stopped at: 14.541 7.764 68.285
system.time(f_dowle(dt1))
user system elapsed
7.452 4.144 19.590 # EDIT has fas...
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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How should I store GUID in MySQL tables?
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104
My DBA asked me when I asked about the best way to store GUIDs for my objects why I needed to st...
Count number of days between two dates
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Andrew FranceAndrew France
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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 +...
“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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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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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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How to align absolutely positioned element to center?
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224
If you set both left and right to zero, and left and right margins to auto you can center an abs...
How to reset or change the MySQL root password?
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34 Answers
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