Hi, set.seed(24) mat1=matrix(rnorm(12),3) set.seed(28) mat2=matrix(rnorm(12),3) indx<- mat1<1 & mat2<1 mat1[indx]<-NA mat2[indx]<-NA mat1 # [,1] [,2] [,3] [,4] #[1,] NA NA NA 0.002311942 #[2,] NA NA NA NA #[3,] NA NA NA 0.598269113 mat2 # [,1] [,2] [,3] [,4] #[1,] NA NA NA 1.841481 #[2,] NA NA NA NA #[3,] NA NA NA 1.520367 A.K.
----- Original Message ----- From: JiangZhengyu <zhyjiang2...@hotmail.com> To: "r-help@r-project.org" <r-help@r-project.org> Cc: Sent: Wednesday, July 3, 2013 5:27 PM Subject: [R] change cell values Dear R experts, I have two matrices (mat1 & mat2) with the same dimension & the cells (row and column) are corresponding to each other. I want to change cell values to NA given values of the corresponding cells in mat1 and mat2 are both <1. E.g. both mat1[2,3] and mat2[2,3] are <1, I will put mat1[2,3]=NA, and mat2[2,3]=NA; if either mat1[2,3]>=1 or mat2[2,3]>=1, I will save both cells. I tried the code, but not working. Could anyone can help fix the problem? mat1[mat1<1&mat2<1]=NA mat2[mat1<1&mat2<1]=NA > mat1=matrix(rnorm(12),3) > mat2=matrix(rnorm(12),3) > mat1 [,1] [,2] [,3] [,4] [1,] -1.3387075 -0.7142333 -0.5614211 0.1846955 [2,] -0.7936087 -0.2215797 -0.3686067 0.7328731 [3,] 0.6505082 0.1826019 1.5577883 -1.5580384 > mat2 [,1] [,2] [,3] [,4] [1,] 0.4331573 -1.8086826 -1.7688123 -1.4278934 [2,] -0.1841451 0.1738648 -1.1086942 1.3065109 [3,] -1.0827245 -0.4143808 -0.6889405 0.4046203 [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
