[R] contour & persp
hellangel_987 at yahoo.com
Sun Feb 7 22:46:49 CET 2010
I have this data set that both x & y are ordered vectors of length 600 & 700 respectively; z is a 600 by 700 matrix whose entry z[i,j] is either a missing value (indicated by 'NaN') or a real number between 0 and 1. The contour function
gives me a blank picture. I guess the reason is that most of z-entries are missing, only less than 1% are non missing.
Is there a way that I could manipulate the data or function to have the non-missing values plotted?
Also, trying function "persp" gives me this error message
Error in persp.default(x, y, z) : invalid 'z' limits
I look at the manual of "persp". I guess, the error message comes from its internal call
zlim = range(z, na.rm = TRUE)
it appears to me that "persp" can't handle missing value yet its manual states clearly
z: a matrix containing the values to be plotted ('NA's are
allowed). Note that ‘x’ can be used instead of ‘z’
Can "persp" handle missing values in z? if the answer is a sounding "yes", how should I do in my case?
Please help, Thanks!
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