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`projectmap(`

`map`, `height` [, hdist=`hdist`,
angle=`angle`, mag=`mag`, xmap=`xmap`, ymap=`ymap`,
size=`size`])

Returns a projected version of the two-dimensional

,
which must be a numerical array. The eye is `map`

units
above the map, measured in units of one map element (as are all linear
measurements in the argument list). The returned array has the same
data type as `height`

. By default, the returned array has 512
by 512 elements and shows the central `map`

by
`height`

elements of `height`

.
`map`

, which defaults to 0, indicates the horizontal
distance of the eye from the chosen center of the projection.
`hdist`

, which defaults to 0, indicates the direction of the
horizontal displacement of the eye, such that an angle of zero yields
the same orientation as `angle``tv,`

, and an increase of the
angle leads to a clockwise rotation of the projection.
`map`

, which defaults to 1, indicates the linear
magnification factor. A greater `mag`

leads to a smaller
fraction of the map being visible in the result. `mag`

and
`xmap`

indicate the map coordinates of the chosen center of
the projection. This location defaults to the center of the map, i.e.,
to `ymap``dimen(`

. `map`)/2

, which defaults to 512,
indicates the linear size of the array that is returned. If
`size`

is a scalar, then its value is taken for both
dimensions. If it is an array, then the first two of its elements are
taken for the dimensions. If `size`

is zero, then the
greatest dimension of the output array spans
`hdist`

elements of the map.
`height`/`mag`