See section 12.13.4 for coordinates in two-dimensional geometry.
The coordinates command takes as argument a point, vector or line.
If the argument is a point,
coordinates returns a list consisting of the abscissa,
ordinate and cote.
Input:
Output:
If the argument is a vector, for example from point A to
point B, then coordinates returns a list of the
coordinates of B-A.
Input:
Output:
If the argument is a line, coordinates returns a list of
two points on the line, in the order determined by the direction of
the line.
Input:
Output:
Input:
Output:
coordinates can also take a sequence or list of points as an
argument; it then returns a sequence or list of the coordinates of
the points.
Input:
Output:
Note that if the argument is a list of real numbers, it is
interpreted as a list of points on the real axis of the plane.
Input:
Output: