## Documentation Center |

Convert latitude-longitude to data grid rows and columns

`[row, col] = setpostn(Z, R, lat, lon)indx = setpostn(...)[row, col, indxPointOutsideGrid] = setpostn(...)`

`[row, col] = setpostn(Z, R, lat, lon)` returns
the row and column indices of the regular data grid `Z` for
the points specified by the vectors `lat` and `lon`. `R` can
be a geographic raster reference object, a referencing vector, or
a referencing matrix.

If `R` is a geographic raster reference object,
its `RasterSize` property must be consistent with `size(Z)`.

If `R` is a referencing vector, it must be
1-by-3 with elements:

[cells/degree northern_latitude_limit western_longitude_limit]

If `R` is
a referencing matrix, it must be 3-by-2 and transform raster row and
column indices to/from geographic coordinates according to:

[lon lat] = [row col 1] * R

If `R` is
a referencing matrix, it must define a (non-rotational, non-skewed)
relationship in which each column of the data grid falls along a meridian
and each row falls along a parallel. Points falling outside the grid
are ignored in `row` and `col`.
All input angles are in degrees.

`indx = setpostn(...)` returns the indices
of `Z` corresponding to the points in `lat` and `lon`.
Points falling outside the grid are ignored in `indx`.

`[row, col, indxPointOutsideGrid] = setpostn(...)` returns
the indices of `lat` and `lon` corresponding
to points outside the grid. These points are ignored in `row` and `col`.

What are the matrix coordinates in `topo` of
Denver, Colorado, at (39.7ºN,105ºW)?

load topo [row,col] = setpostn(topo,topolegend,39.7,105) row = 130 col = 105

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