# Copyright 2004 by Harry Zuzan. All rights reserved. # This code is part of the Biopython distribution and governed by its # license. Please see the LICENSE file that should have been included # as part of this package. """ No version number yet. Classes for accessing the information in Affymetrix cel files. class CelParser: parses cel files class CelRecord: stores the information from a cel file """ # import _cel from Bio.ParserSupport import AbstractConsumer from Numeric import * class CelScanner: """Scannner for Affymetrix CEL files. Methods: feed Feed data into the scanner. The scanner generates (and calls the consumer) the following types of events: Rows - the number of rows on the microarray Cols - the number of columns on the microarray StartIntensity - generated when the section [INTENSITY] is found ReadIntensity - one line in the section [INTENSITY] """ def feed(self, handle, consumer): """scanner.feed(handle, consumer) Feed in a handle to a Cel file for scanning. handle is a file-like object that contains the Cel file. consumer is a Consumer object that will receive events as the report is scanned. """ section = "" for line in handle: if line.strip()=="": continue if line[0]=="[": section = "" if line[:8]=="[HEADER]": section = "HEADER" elif line[:11]=="[INTENSITY]": section = "INTENSITY" consumer.StartIntensity() continue if section=="HEADER": keyword, value = line.split("=", 1) if keyword=="Cols": consumer.Cols(value) if keyword=="Rows": consumer.Rows(value) continue elif section=="INTENSITY": if "=" in line: continue consumer.ReadIntensity(line) class CelConsumer(AbstractConsumer): def __init__(self): self._mean = None self._stdev = None self._npix = None def Cols(self, value): self._cols = int(value) def Rows(self, value): self._rows = int(value) def StartIntensity(self): self._mean = zeros((self._rows, self._cols), Float) self._stdev = zeros((self._rows, self._cols), Float) self._npix = zeros((self._rows, self._cols), Int) def ReadIntensity(self, line): y, x, mean, stdev, npix = map(float, line.split()) x = int(x) y = int(y) self._mean[x,y] = mean self._stdev[x,y] = stdev self._npix[x,y] = int(npix) class CelRecord: """ Stores the information in a cel file Needs error handling. Needs to know the chip design. """ def __init__(self, data_dict): """ Pass the data attributes as a dictionary. """ from copy import deepcopy as dcopy self._intensities = dcopy(data_dict['intensities']) self._stdevs = dcopy(data_dict['stdevs']) self._npix = dcopy(data_dict['npix']) self._nrows, self._ncols = self._intensities.shape def intensities(self): """ Return a two dimensional array of probe cell intensities. Dimension 1 -> rows Dimension 2 -> columns """ return self._intensities def stdevs(self): """ Return a two dimensional array of probe cell standard deviations. Dimension 1 -> rows Dimension 2 -> columns """ return self._stdevs def npix(self): """ Return a two dimensional array of the number of pixels in a probe cell. Dimension 1 -> rows Dimension 2 -> columns """ return self._npix def nrows(self): """ The number of rows of probe cells in an array. """ return self._nrows def ncols(self): """ The number of columns of probe cells in an array. """ return self._ncols def size(self): """ The size of the probe cell array as a tuple (nrows,ncols). """ return self._nrows, self._ncols class CelParser: """ Takes a handle to an Affymetrix cel file, parses the file and returns an instance of a CelRecord This class needs error handling. """ def __init__(self, handle=None): """ Usually load the class with the cel file (not file name) as an argument. """ self._intensities = None self._stdevs = None self._npix = None if handle is not None: self.parse(handle) def parse(self, handle): """ Takes a handle to a cel file, parses it and stores it in the three arrays. There is more information in the cel file that could be retrieved and stored in CelRecord. The chip type should be a priority. """ # (self._intensities, self._stdevs, self._npix) = _cel.parse(data) scanner = CelScanner() consumer = CelConsumer() scanner.feed(handle, consumer) self._intensities = consumer._mean self._stdevs = consumer._stdev self._npix = consumer._npix self._nrows = self._intensities.shape[0] self._ncols = self._intensities.shape[1] def __call__(self): """ Returns the parsed data as a CelRecord. """ record_dict = {} record_dict['intensities'] = self._intensities record_dict['stdevs'] = self._stdevs record_dict['npix'] = self._npix return CelRecord(record_dict)