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In R, how to get an object's name after it is sent to a function?
...
The old deparse-substitute trick:
a<-data.frame(x=1:10,y=1:10)
test<-function(z){
mean.x<-mean(z$x)
nm <-deparse(substitute(z))
print(nm)
return(mean.x)}
test(a)
#[1] "a" ... this is the side-effect of the print() call
# ... you could have...
Elegant way to combine multiple collections of elements?
...rary number of collections, each containing objects of the same type (for example, List<int> foo and List<int> bar ). If these collections were themselves in a collection (e.g., of type List<List<int>> , I could use SelectMany to combine them all into one collection.
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How do I put two increment statements in a C++ 'for' loop?
... operator at all. I checked that in GCC as follows:
int i=0;
int a=5;
int x=0;
for(i; i<5; x=i++,a++){
printf("i=%d a=%d x=%d\n",i,a,x);
}
I was expecting x to pick up the original value of a, so it should have displayed 5,6,7.. for x. What I got was this
i=0 a=5 x=0
i=1 a=6 x=0
i=2 a=7 ...
How to determine if a point is in a 2D triangle? [closed]
...ou started:
float sign (fPoint p1, fPoint p2, fPoint p3)
{
return (p1.x - p3.x) * (p2.y - p3.y) - (p2.x - p3.x) * (p1.y - p3.y);
}
bool PointInTriangle (fPoint pt, fPoint v1, fPoint v2, fPoint v3)
{
float d1, d2, d3;
bool has_neg, has_pos;
d1 = sign(pt, v1, v2);
d2 = sign(pt, ...
How to count certain elements in array?
... just to compare it to a value is not elegant.
– Felix Kling
May 25 '11 at 8:33
2
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Combine two columns of text in pandas dataframe
I have a 20 x 4000 dataframe in Python using pandas. Two of these columns are named Year and quarter . I'd like to create a variable called period that makes Year = 2000 and quarter= q2 into 2000q2 .
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How can I get the source code of a Python function?
...ting the lines of source code, and tuple[1] is the line number in the context of execution where it was run. In IPython; this is the line number within the cell not the overall notebook
– The Red Pea
Sep 23 '14 at 5:32
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How to remove outliers from a dataset
...d of data, they are given an age and a beauty rating from 1-5. When I do boxplots of this data (ages across the X-axis, beauty ratings across the Y-axis), there are some outliers plotted outside the whiskers of each box.
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How to make rpm auto install dependencies
...cal repository, e.g. /home/user/repo.
Move the RPMs into that directory.
Fix some ownership and filesystem permissions:
# chown -R root.root /home/user/repo
Install the createrepo package if not installed yet, and run
# createrepo /home/user/repo
# chmod -R o-w+r /home/user/repo
Create a reposit...
“Cloning” row or column vectors
Sometimes it is useful to "clone" a row or column vector to a matrix. By cloning I mean converting a row vector such as
9 A...