danse_reader.py @ 25dd9c9

Last change on this file since 25dd9c9 was 235f514, checked in by andyfaff, 8 years ago
MAINT: replace '== None' by 'is None'
Property mode set to `100644`
File size: 10.2 KB

Line
1	"""
2	DANSE/SANS file reader
3	"""
4	############################################################################
5	#This software was developed by the University of Tennessee as part of the
6	#Distributed Data Analysis of Neutron Scattering Experiments (DANSE)
7	#project funded by the US National Science Foundation.
8	#If you use DANSE applications to do scientific research that leads to
9	#publication, we ask that you acknowledge the use of the software with the
10	#following sentence:
11	#This work benefited from DANSE software developed under NSF award DMR-0520547.
12	#copyright 2008, University of Tennessee
13	#############################################################################
14	import math
15	import os
16	import sys
17	import numpy as np
18	import logging
19	from sas.sascalc.dataloader.data_info import Data2D, Detector
20	from sas.sascalc.dataloader.manipulations import reader2D_converter
21
22	logger = logging.getLogger(__name__)
23
24	# Look for unit converter
25	has_converter = True
26	try:
27	from sas.sascalc.data_util.nxsunit import Converter
28	except:
29	has_converter = False
30
31
32	class Reader:
33	"""
34	Example data manipulation
35	"""
36	## File type
37	type_name = "DANSE"
38	## Wildcards
39	type = ["DANSE files (.sans)\|.sans"]
40	## Extension
41	ext = ['.sans', '.SANS']
42
43	def read(self, filename=None):
44	"""
45	Open and read the data in a file
46	@param file: path of the file
47	"""
48
49	read_it = False
50	for item in self.ext:
51	if filename.lower().find(item) >= 0:
52	read_it = True
53
54	if read_it:
55	try:
56	datafile = open(filename, 'r')
57	except:
58	raise RuntimeError,"danse_reader cannot open %s" % (filename)
59
60	# defaults
61	# wavelength in Angstrom
62	wavelength = 10.0
63	# Distance in meter
64	distance = 11.0
65	# Pixel number of center in x
66	center_x = 65
67	# Pixel number of center in y
68	center_y = 65
69	# Pixel size [mm]
70	pixel = 5.0
71	# Size in x, in pixels
72	size_x = 128
73	# Size in y, in pixels
74	size_y = 128
75	# Format version
76	fversion = 1.0
77
78	output = Data2D()
79	output.filename = os.path.basename(filename)
80	detector = Detector()
81	output.detector.append(detector)
82
83	output.data = np.zeros([size_x,size_y])
84	output.err_data = np.zeros([size_x, size_y])
85
86	data_conv_q = None
87	data_conv_i = None
88
89	if has_converter == True and output.Q_unit != '1/A':
90	data_conv_q = Converter('1/A')
91	# Test it
92	data_conv_q(1.0, output.Q_unit)
93
94	if has_converter == True and output.I_unit != '1/cm':
95	data_conv_i = Converter('1/cm')
96	# Test it
97	data_conv_i(1.0, output.I_unit)
98
99	read_on = True
100	while read_on:
101	line = datafile.readline()
102	if line.find("DATA:") >= 0:
103	read_on = False
104	break
105	toks = line.split(':')
106	if toks[0] == "FORMATVERSION":
107	fversion = float(toks[1])
108	if toks[0] == "WAVELENGTH":
109	wavelength = float(toks[1])
110	elif toks[0] == "DISTANCE":
111	distance = float(toks[1])
112	elif toks[0] == "CENTER_X":
113	center_x = float(toks[1])
114	elif toks[0] == "CENTER_Y":
115	center_y = float(toks[1])
116	elif toks[0] == "PIXELSIZE":
117	pixel = float(toks[1])
118	elif toks[0] == "SIZE_X":
119	size_x = int(toks[1])
120	elif toks[0] == "SIZE_Y":
121	size_y = int(toks[1])
122
123	# Read the data
124	data = []
125	error = []
126	if fversion == 1.0:
127	data_str = datafile.readline()
128	data = data_str.split(' ')
129	else:
130	read_on = True
131	while read_on:
132	data_str = datafile.readline()
133	if len(data_str) == 0:
134	read_on = False
135	else:
136	toks = data_str.split()
137	try:
138	val = float(toks[0])
139	err = float(toks[1])
140	if data_conv_i is not None:
141	val = data_conv_i(val, units=output._yunit)
142	err = data_conv_i(err, units=output._yunit)
143	data.append(val)
144	error.append(err)
145	except:
146	logger.info("Skipping line:%s,%s" %(data_str,
147	sys.exc_value))
148
149	# Initialize
150	x_vals = []
151	y_vals = []
152	ymin = None
153	ymax = None
154	xmin = None
155	xmax = None
156
157	# Qx and Qy vectors
158	theta = pixel / distance / 100.0
159	stepq = 4.0 * math.pi / wavelength * math.sin(theta / 2.0)
160	for i_x in range(size_x):
161	theta = (i_x - center_x + 1) * pixel / distance / 100.0
162	qx = 4.0 * math.pi / wavelength * math.sin(theta / 2.0)
163
164	if has_converter == True and output.Q_unit != '1/A':
165	qx = data_conv_q(qx, units=output.Q_unit)
166
167	x_vals.append(qx)
168	if xmin is None or qx < xmin:
169	xmin = qx
170	if xmax is None or qx > xmax:
171	xmax = qx
172
173	ymin = None
174	ymax = None
175	for i_y in range(size_y):
176	theta = (i_y - center_y + 1) * pixel / distance / 100.0
177	qy = 4.0 * math.pi / wavelength * math.sin(theta/2.0)
178
179	if has_converter == True and output.Q_unit != '1/A':
180	qy = data_conv_q(qy, units=output.Q_unit)
181
182	y_vals.append(qy)
183	if ymin is None or qy < ymin:
184	ymin = qy
185	if ymax is None or qy > ymax:
186	ymax = qy
187
188	# Store the data in the 2D array
189	i_x = 0
190	i_y = -1
191
192	for i_pt in range(len(data)):
193	try:
194	value = float(data[i_pt])
195	except:
196	# For version 1.0, the data were still
197	# stored as strings at this point.
198	msg = "Skipping entry (v1.0):%s,%s" % (str(data[i_pt]),
199	sys.exc_value)
200	logger.info(msg)
201
202	# Get bin number
203	if math.fmod(i_pt, size_x) == 0:
204	i_x = 0
205	i_y += 1
206	else:
207	i_x += 1
208
209	output.data[i_y][i_x] = value
210	if fversion>1.0:
211	output.err_data[i_y][i_x] = error[i_pt]
212
213	# Store all data
214	# Store wavelength
215	if has_converter == True and output.source.wavelength_unit != 'A':
216	conv = Converter('A')
217	wavelength = conv(wavelength,
218	units=output.source.wavelength_unit)
219	output.source.wavelength = wavelength
220
221	# Store distance
222	if has_converter == True and detector.distance_unit != 'm':
223	conv = Converter('m')
224	distance = conv(distance, units=detector.distance_unit)
225	detector.distance = distance
226
227	# Store pixel size
228	if has_converter == True and detector.pixel_size_unit != 'mm':
229	conv = Converter('mm')
230	pixel = conv(pixel, units=detector.pixel_size_unit)
231	detector.pixel_size.x = pixel
232	detector.pixel_size.y = pixel
233
234	# Store beam center in distance units
235	detector.beam_center.x = center_x * pixel
236	detector.beam_center.y = center_y * pixel
237
238	# Store limits of the image (2D array)
239	xmin = xmin - stepq / 2.0
240	xmax = xmax + stepq / 2.0
241	ymin = ymin - stepq /2.0
242	ymax = ymax + stepq / 2.0
243
244	if has_converter == True and output.Q_unit != '1/A':
245	xmin = data_conv_q(xmin, units=output.Q_unit)
246	xmax = data_conv_q(xmax, units=output.Q_unit)
247	ymin = data_conv_q(ymin, units=output.Q_unit)
248	ymax = data_conv_q(ymax, units=output.Q_unit)
249	output.xmin = xmin
250	output.xmax = xmax
251	output.ymin = ymin
252	output.ymax = ymax
253
254	# Store x and y axis bin centers
255	output.x_bins = x_vals
256	output.y_bins = y_vals
257
258	# Units
259	if data_conv_q is not None:
260	output.xaxis("\\rm{Q_{x}}", output.Q_unit)
261	output.yaxis("\\rm{Q_{y}}", output.Q_unit)
262	else:
263	output.xaxis("\\rm{Q_{x}}", 'A^{-1}')
264	output.yaxis("\\rm{Q_{y}}", 'A^{-1}')
265
266	if data_conv_i is not None:
267	output.zaxis("\\rm{Intensity}", output.I_unit)
268	else:
269	output.zaxis("\\rm{Intensity}", "cm^{-1}")
270
271	if not fversion >= 1.0:
272	msg = "Danse_reader can't read this file %s" % filename
273	raise ValueError, msg
274	else:
275	logger.info("Danse_reader Reading %s \n" % filename)
276
277	# Store loading process information
278	output.meta_data['loader'] = self.type_name
279	output = reader2D_converter(output)
280	return output
281
282	return None

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source: sasview/src/sas/sascalc/dataloader/readers/danse_reader.py @ 25dd9c9

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