See section 13.13.13 for checking for rhombuses in three-dimensional geometry.
The is_rhombus command takes as argument a geometric object or four points.
is_rhombus returns 1 or 2 if the object is
a rhombus; it returns 1 if the object is a rhombus but not a
square and 2 if the object is a square. The command returns
0 if the object is not a rhombus.
Input:
Output:
Input:
then:
Input:
Input:
then:
Input:
Note that K[0] is a rhombus since K is a list made
of a rhombus and vertices C and D. Entering
affix(C,D) returns -sqrt(2)-i,-sqrt(2)+i.
Input:
Output: