Scripts: angle.py

# Measure the angle between two axes, each axis specified by two atoms.
#
# This was written to measure angles between axes determined by the
# "measure rotation" command which creates axis models containing two atoms
# connected by a bond defining the axis.  If models #2 and #3 are two such
# axis models this script can be run using Chimera command
#
#       runscript angle.py #2 #3
#
a1, a2 = arguments

from Midas.midas_text import _parseAtomBondAxis as parseAxis
# Axis vector and base point given in model coordinate system
lv1, p1, os1 = parseAxis(a1)
lv2, p2, os2 = parseAxis(a2)

# Get axis vectors in global coordinate system.
v1 = os1.xform.apply(lv1)
v2 = os2.xform.apply(lv2)

# Calculate angle
a = chimera.angle(v1,v2)

from chimera.replyobj import status, info
msg = 'Angle %s to %s is %.4g degrees' % (a1, a2, a)
status(msg)
info(msg + '\n')