# pindex: Get Values in a Matrix by Pair-wise Indices In ComplexHeatmap: Make Complex Heatmaps

## Description

Get Values in a Matrix by Pair-wise Indices

## Usage

 `1` ```pindex(m, i, j) ```

## Arguments

 `m` A matrix or a 3-dimension array. `i` Row indices or the indices in the first dimension. `j` Column indicies or the indices in the second dimension.

## Value

If `m` is a matrix, the value returned is a vector `c(m[i1, j1], m[i2, j2], ...)`'.

If `m` is an array, the value returned is a matrix `rbind(m[i1, j1, ], m[i2, j2, ], ...)`'.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14``` ```m = matrix(rnorm(100), 10) m2 = m[m > 0] ind = do.call("rbind", lapply(1:10, function(ci) { i = which(m[, ci] > 0) cbind(i = i, j = rep(ci, length(i))) })) pindex(m, ind[, 1], ind[, 2]) identical(pindex(m, ind[, 1], ind[, 2]), m[m > 0]) # 3d array arr = array(1:27, dim = c(3, 3, 3)) pindex(arr, 1:2, 2:3) identical(pindex(arr, 1:2, 2:3), rbind(arr[1, 2, ], arr[2, 3, ])) ```

ComplexHeatmap documentation built on Nov. 14, 2020, 2:01 a.m.