R plot of a matrix of complex numbers -

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i have matrix of complex values.

if issue command:

plot(mymatrix)

then shows on graphics device kind of scatterplot, x-axis labeled re(mymatrix) , y-axis im(mymatrix). shows information i'm looking for, can see distinct clusters, cannot see 1 column.

my questions :

  1. i assume there 1 point per matrix row. right ?
  2. how calculated re(mymatrix) each row vector ?

it not re(mymatrix[1,row]), seems mix of values of row vector. able these values, know how compute them r.

no, there 1 point each matrix element. 

set.seed(42) mat <- matrix(complex(real = rnorm(16), imaginary = rlnorm(16)), 4)  plot(mat)  points(re(mat[1,1]), im(mat[1,1]), col = "red", pch = ".", cex = 5)

look red dot: resulting plot

you'd same plot, if plotted vector instead of matrix, i.e., plot(c(mat)).

this happens because plot.default calls xy.coords , function contains following code:

else if (is.complex(x)) {             y <- im(x)             x <- re(x)             xlab <- paste0("re(", ylab, ")")             ylab <- paste0("im(", ylab, ")")         }         else if (is.matrix(x) || is.data.frame(x)) {

this means, fact input complex takes priority on being matrix.


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