| Allegro CL version 8.2This page is new in 8.2. |

**Arguments: ***
point1 point2 x
*

Returns the y coordinate where a line has a
particular ** x** coordinate,
or

`nil`

for a vertical line.
The first two arguments are position objects that specify any two
distinct points on the line. The last argument is a real number for
the x coordinate. The returned value is a real number
or `nil`

.

As usual, position objects should contain integers. See
**make-position**. See also
**line-x-at-y** and
**line-y-at-x-x-y**.

Copyright (c) 1998-2012, Franz Inc. Oakland, CA., USA. All rights reserved.

Documentation for Allegro CL version 8.2. This page is new in the 8.2 release.

Created 2010.1.21.

| Allegro CL version 8.2This page is new in 8.2. |