Documentation/sphinx/source/pyplots/trajectory_simple.py

   1 #!/usr/bin/env python
   2 # -*- coding: utf-8 -*-
   3
   4 import math
   5 import numpy
   6
   7 import matplotlib.pyplot as plt
   8
   9 from gi.repository import GLib
  10 from gi.repository import Hkl
  11
  12
  13 sample = Hkl.Sample.new("toto")
  14 lattice = Hkl.Lattice.new(1.54, 1.54, 1.54,
  15                           math.radians(90),
  16                           math.radians(90),
  17                           math.radians(90))
  18 sample.lattice_set(lattice)
  19
  20 detector = Hkl.Detector.factory_new(Hkl.DetectorType(0))
  21
  22 factory = Hkl.factories()['K6C']
  23 geometry = factory.create_new_geometry()
  24 axes_names = geometry.axes_names_get()
  25
  26 # set the initial position
  27 geometry.axes_values_set([0, 120, 0, -90, 0, 60], Hkl.UnitEnum.USER)
  28
  29 # get all engines for a given configuration
  30 engines = factory.create_new_engine_list()
  31
  32 # prepare the engines to work with the related geometry, detector and
  33 # sample
  34 engines.init(geometry, detector, sample)
  35
  36 #[0, 0, 1] -> [0, 1, 1]
  37 n = 10
  38 h = numpy.linspace(0, 0, n + 1)
  39 k = numpy.linspace(0, 1, n + 1)
  40 l = numpy.linspace(1, 1, n + 1)
  41
  42 # get the hkl engine
  43 hkl = engines.engine_get_by_name("hkl")
  44 pseudo_axes_names = ["h", "k", "l"]
  45
  46 # compute the trajectory
  47 motors_positions = []
  48 for idx, hh, kk, ll in zip(range(n), h, k, l):
  49     try:
  50         solutions = hkl.pseudo_axes_values_set([hh, kk, ll],
  51                                                Hkl.UnitEnum.USER)
  52         first_solution = solutions.items()[0]
  53         # if no exception raised we have at least one solution
  54         # move the diffractometer to the solution
  55         engines.select_solution(first_solution)
  56         motors_positions.append(geometry.axes_values_get(Hkl.UnitEnum.USER))
  57     except GLib.GError, err:
  58         pass
  59
  60 plt.subplot(1, 2, 1)
  61 plt.title("motors trajectory (1st solution)")
  62 # reorder the motors_positions for the plot
  63 motors_positions = numpy.array(motors_positions).T
  64 for y, name in zip(motors_positions, axes_names):
  65     plt.plot(y, 'o-', label=name)
  66 plt.legend(loc=2)
  67 plt.ylim(-180, 180)
  68 plt.xlabel("trajectory point index")
  69 plt.ylabel("motor position (Degree)")
  70
  71 plt.subplot(1, 2, 2)
  72 plt.title("hkl trajectory")
  73 hkl_positions = numpy.array([h, k, l])
  74 for y, name in zip(hkl_positions, pseudo_axes_names):
  75     plt.plot(y, 'o-', label=name)
  76 plt.legend(loc=2)
  77 plt.ylim(-0.1, 1.1)
  78 plt.xlabel("trajectory point index")
  79 plt.ylabel("pseudo motor position")