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`ssfctopolar(`

`ssfc` [, `level`)

Converts SSFCs (SierpiÅski Surface-Filling Coordinates) to polar coordinates. An ssfc (http://ssfc.quae.nl) indicates a position on the surface of a sphere with just one coordinate rather than with the usual two coordinates.

If

is of an integer type, then its values are
interpreted as ssfc indices at the indicated `ssfc`

, and
are interpreted modulo `level``2^`

. If no `level`

is indicated, then it is taken to be equal to the least number that
accommodates the greatest value found in `level`

, such that
`ssfc``max(`

.
`ssfc` < 2^`level`

If

is of a floating-point type, then its values are
interpreted modulo 1, as decimal SSFCs. If `ssfc`

is not
specified, then it is taken equal to the maxmimum value commensurate
with the data type.
`level`

The returned value is an array with 3 elements in its first dimension,
and with a set of 3 values for each value of

. The 3
values are the latitude, longitude, and angular size, all measured in
radians. Multiply by `ssfc`

to get degrees (#rad).
The angular size is a measure for the size of the area on the surface
of the sphere that is indicated by the ssfc at the specified level.
`#rad`

See also: polartossfc