[Qgis-user] latitude map

[A. Marcia BARBOSA]

Hi,

What is the best way of getting a raster map (global coverage,
lat-long coordinates) in which the value of each pixel is its
latitude? I'm thinking of digitizing the upper and lower horizontal
limits of the region, giving them the values of the maximum and
minimum latitude (respectively), and then interpolating them. But
which would be the most appropriate interpolation method? Or is there
a better way of doing this?

Thanks in advance,
Márcia

PS: apologies for cross-posting