Differences

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--- get_coordinates [2019/09/12 08:25] – johnsoevans
+++ get_coordinates [2025/09/19 15:18] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== Getting Coordinates ======
+There are various macros to Get coordinates of atoms for use in other equations.  Different ones are needed for regular sites and for point_for_sites in rigid bodies.  Note that you can't use information from point_for_sites of a rigid body in regular sites.
+For regular sites use:
+<code topas>
+{ Get(Find_Child(Get(site_recs), site_name), x) }
+{ Get(Find_Child(Get(site_recs), site_name), y) }
+{ Get(Find_Child(Get(site_recs), site_name), z) }
+</code>
+If it's more convenient use the macro:
+<code topas>
+macro Get_x(site_name) { Get(Find_Child(Get(site_recs), site_name), x) }
+macro Get_y(site_name) { Get(Find_Child(Get(site_recs), site_name), y) }
+macro Get_z(site_name) { Get(Find_Child(Get(site_recs), site_name), z) }
+</code>
+For rigid body point for sites you can get the coordinates in cartesian space with the macro:
+<code topas>
+macro & Get_x(site_name) { Point(site_name, rx) }
+macro & Get_y(site_name) { Point(site_name, ry) }
+macro & Get_z(site_name) { Point(site_name, rz) }
+</code>
+In the future it might be possible to work with the fractional coordinates of other atoms in the rigid body by switching from rx to ua coordinates with topas.inc macros:
+<code topas>
+Point_ua(site_name)
+Point_ub(site_name)
+Point_uc(site_name)
+</code>