# map2pix

Convert map coordinates to pixel coordinates

## Syntax

`[row,col] = map2pix(R,x,y)p = map2pix(R,x,y)[...] = map2pix(R,s)`

## Description

`[row,col] = map2pix(R,x,y)` calculates pixel coordinates `row,col` from map coordinates `x,y`. `R` is either a 3-by-2 referencing matrix defining a 2-dimensional affine transformation from intrinsic pixel coordinates to map coordinates, or a map raster reference object. `x` and `y` are vectors or arrays of matching size. The outputs `row` and `col` have the same size as `x` and `y`.

`p = map2pix(R,x,y)` combines `row` and `col` into a single array `p`. If `x` and `y` are column vectors of length `n`, then `p` is an `n`-by-2 matrix and each `p(k,:)` specifies the pixel coordinates of a single point. Otherwise, `p` has size `[size(row) 2]`, and `p(k1,k2,...,kn,:)` contains the pixel coordinates of a single point.

`[...] = map2pix(R,s)` combines `x` and `y` into a single array `s`. If `x` and `y` are column vectors of length `n`, the `s` should be an `n`-by-2 matrix such that each row `(s(k,:))` specifies the map coordinates of a single point. Otherwise, `s` should have size `[size(X) 2]`, and `s(k1,k2,...,kn,:)` should contain the map coordinates of a single point.

## Examples

```% Find the pixel coordinates for the spatial coordinates % (207050, 912900) R = worldfileread('concord_ortho_w.tfw'); [r,c] = map2pix(R, 207050, 912900);```