R image() plots matrix rotated?
You could reverse the matrix, then transpose.
mat1 <- apply(mat1, 2, rev)
image(1:3, 1:3, t(mat1))
It's confusing because it draws by row from bottom up, but R indexes matrices by column, top down. So, the pixels in the first row, from left to right, correspond to the first column in the matrix, top down.
when viewing a matrix as image using something like this:
m <- some matrix
image(m)
R turns it upside down. After some small headaches, I found this quick fix.
image(m[,nrow(m):1])
nrow(m)
gives the number of rows of your matrix
nrow(m):1
makes a sequence backwards