Hello R, I have data in txt file of n columns like this: x y1 .....yn 1 100 2 50 3 10 4 200 5 20 I need to find coordinates for each maxima e.g.: [x,y1],[x,y2]...[x,yn] a=read.table() attach(a) b=y1<-x max(b) returns only value of y but no corresponding x value -- View this message in context: http://r.789695.n4.nabble.com/Finding-coordinates-for-maximum-of-a-function-tp3355369p3355369.html Sent from the R help mailing list archive at Nabble.com.
This is where which.max() comes in handy
n<-length(x)
x.c<-rep(0,n)
for(i in 1:n){
x.c[i]<-which.max[y1]
}
x.c is then a vector of x coordinates for the maximum for columns
y1,y2,...,yn
--
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Sent from the R help mailing list archive at Nabble.com.
It occured to me: x[max(y)] simple isn't it? -- View this message in context: http://r.789695.n4.nabble.com/Finding-coordinates-for-maximum-of-a-function-tp3355369p3356117.html Sent from the R help mailing list archive at Nabble.com.
That actually won't work. max(y) will give a value, not a coordinate, so x[max(y)] is definitely not what you want. -- View this message in context: http://r.789695.n4.nabble.com/Finding-coordinates-for-maximum-of-a-function-tp3355369p3356483.html Sent from the R help mailing list archive at Nabble.com.