Source code for sas.sascalc.file_converter.bsl_loader

from sas.sascalc.file_converter.core.bsl_loader import CLoader
from sas.sascalc.dataloader.data_info import Data2D
from copy import deepcopy
import os
import numpy as np

[docs]class BSLParsingError(Exception): pass
[docs]class BSLLoader(CLoader): """ Loads 2D SAS data from a BSL file. CLoader is a C extension (found in c_ext/bsl_loader.c) See for more info on the BSL file format. """ def __init__(self, filename): """ Parses the BSL header file and sets instance variables apropriately :param filename: Path to the BSL header file """ header_file = open(filename, 'r') data_info = {} is_valid = True err_msg = "" [folder, filename] = os.path.split(filename) # SAS data will be in file Xnn001.mdd sasdata_filename = filename.replace('000.', '001.') if sasdata_filename == filename: err_msg = ("Invalid header filename {}.\nShould be of the format " "Xnn000.XXX where X is any alphanumeric character and n is any" " digit.").format(filename) raise BSLParsingError(err_msg) # First 2 lines are headers header_file.readline() header_file.readline() while True: metadata = header_file.readline().strip() metadata = metadata.split() data_filename = header_file.readline().strip() if len(metadata) != 10: is_valid = False err_msg = "Invalid header file: {}".format(filename) break if data_filename != sasdata_filename: last_file = (metadata[9] == '0') if last_file: # Reached last file we have metadata for is_valid = False err_msg = "No metadata for {} found in header file: {}" err_msg = err_msg.format(sasdata_filename, filename) break continue try: data_info = { 'filename': os.path.join(folder, data_filename), 'pixels': int(metadata[0]), 'rasters': int(metadata[1]), 'frames': int(metadata[2]), 'swap_bytes': int(metadata[3]) } except: is_valid = False err_msg = "Invalid metadata in header file for {}" err_msg = err_msg.format(sasdata_filename) break header_file.close() if not is_valid: raise BSLParsingError(err_msg) CLoader.__init__(self, data_info['filename'], data_info['frames'], data_info['pixels'], data_info['rasters'], data_info['swap_bytes'])
[docs] def load_frames(self, frames): frame_data = [] # Prepare axis values (arbitrary scale) x = self.n_rasters * range(1, self.n_pixels+1) y = [self.n_pixels * [i] for i in range(1, self.n_rasters+1)] y = np.reshape(y, (1, self.n_pixels*self.n_rasters))[0] x_bins = x[:self.n_pixels] y_bins = y[0::self.n_pixels] for frame in frames: self.frame = frame raw_frame_data = self.load_data() data2d = Data2D(data=raw_frame_data, qx_data=x, qy_data=y) data2d.x_bins = x_bins data2d.y_bins = y_bins data2d.Q_unit = '' # Using arbitrary units frame_data.append(data2d) return frame_data
def __setattr__(self, name, value): if name == 'filename': return self.set_filename(value) elif name == 'n_frames': return self.set_n_frames(value) elif name == 'frame': return self.set_frame(value) elif name == 'n_pixels': return self.set_n_pixels(value) elif name == 'n_rasters': return self.set_n_rasters(value) elif name == 'swap_bytes': return self.set_swap_bytes(value) return CLoader.__setattr__(self, name, value) def __getattr__(self, name): if name == 'filename': return self.get_filename() elif name == 'n_frames': return self.get_n_frames() elif name == 'frame': return self.get_frame() elif name == 'n_pixels': return self.get_n_pixels() elif name == 'n_rasters': return self.get_n_rasters() elif name == 'swap_bytes': return self.get_swap_bytes() return CLoader.__getattr__(self, name)