Source code for deeptools.heatmapper

import sys
import gzip
from collections import OrderedDict
import numpy as np
from copy import deepcopy

import pyBigWig
from deeptools import getScorePerBigWigBin
from deeptools import mapReduce
from deeptools.utilities import toString, toBytes, smartLabels
from deeptools.heatmapper_utilities import getProfileTicks


old_settings = np.seterr(all='ignore')


[docs] def chopRegions(exonsInput, left=0, right=0): """ exons is a list of (start, end) tuples. The goal is to chop these into separate lists of tuples, to take care or unscaled regions. "left" and "right" denote regions of a given size to exclude from the normal binning process (unscaled regions). This outputs three lists of (start, end) tuples: leftBins: 5' unscaled regions bodyBins: body bins for scaling rightBins: 3' unscaled regions In addition are two integers padLeft: Number of bases of padding on the left (due to not being able to fulfill "left") padRight: As above, but on the right side """ leftBins = [] rightBins = [] padLeft = 0 padRight = 0 exons = deepcopy(exonsInput) while len(exons) > 0 and left > 0: width = exons[0][1] - exons[0][0] if width <= left: leftBins.append(exons[0]) del exons[0] left -= width else: leftBins.append((exons[0][0], exons[0][0] + left)) exons[0] = (exons[0][0] + left, exons[0][1]) left = 0 if left > 0: padLeft = left while len(exons) > 0 and right > 0: width = exons[-1][1] - exons[-1][0] if width <= right: rightBins.append(exons[-1]) del exons[-1] right -= width else: rightBins.append((exons[-1][1] - right, exons[-1][1])) exons[-1] = (exons[-1][0], exons[-1][1] - right) right = 0 if right > 0: padRight = right return leftBins, exons, rightBins[::-1], padLeft, padRight
[docs] def chopRegionsFromMiddle(exonsInput, left=0, right=0): """ Like chopRegions(), above, but returns two lists of tuples on each side of the center point of the exons. The steps are as follow: 1) Find the center point of the set of exons (e.g., [(0, 200), (300, 400), (800, 900)] would be centered at 200) * If a given exon spans the center point then the exon is split 2) The given number of bases at the end of the left-of-center list are extracted * If the set of exons don't contain enough bases, then padLeft is incremented accordingly 3) As above but for the right-of-center list 4) A tuple of (#2, #3, pading on the left, and padding on the right) is returned """ leftBins = [] rightBins = [] size = sum([x[1] - x[0] for x in exonsInput]) middle = size // 2 cumulativeSum = 0 padLeft = 0 padRight = 0 exons = deepcopy(exonsInput) # Split exons in half for exon in exons: size = exon[1] - exon[0] if cumulativeSum >= middle: rightBins.append(exon) elif cumulativeSum + size < middle: leftBins.append(exon) else: # Don't add 0-width exonic bins! if exon[0] < exon[1] - cumulativeSum - size + middle: leftBins.append((exon[0], exon[1] - cumulativeSum - size + middle)) if exon[1] - cumulativeSum - size + middle < exon[1]: rightBins.append((exon[1] - cumulativeSum - size + middle, exon[1])) cumulativeSum += size # Trim leftBins/adjust padLeft lSum = sum([x[1] - x[0] for x in leftBins]) if lSum > left: lSum = 0 for i, exon in enumerate(leftBins[::-1]): size = exon[1] - exon[0] if lSum + size > left: leftBins[-i - 1] = (exon[1] + lSum - left, exon[1]) break lSum += size if lSum == left: break i += 1 if i < len(leftBins): leftBins = leftBins[-i:] elif lSum < left: padLeft = left - lSum # Trim rightBins/adjust padRight rSum = sum([x[1] - x[0] for x in rightBins]) if rSum > right: rSum = 0 for i, exon in enumerate(rightBins): size = exon[1] - exon[0] if rSum + size > right: rightBins[i] = (exon[0], exon[1] - rSum - size + right) break rSum += size if rSum == right: break rightBins = rightBins[:i + 1] elif rSum < right: padRight = right - rSum return leftBins, rightBins, padLeft, padRight
[docs] def trimZones(zones, maxLength, binSize, padRight): """ Given a (variable length) list of lists of (start, end) tuples, trim/remove and tuple that extends past maxLength (e.g., the end of a chromosome) Returns the trimmed zones and padding """ output = [] for zone, nbins in zones: outZone = [] changed = False for reg in zone: if reg[0] >= maxLength: changed = True padRight += reg[1] - reg[0] continue if reg[1] > maxLength: changed = True padRight += reg[1] - maxLength reg = (reg[0], maxLength) if reg[1] > reg[0]: outZone.append(reg) if changed: nBins = sum(x[1] - x[0] for x in outZone) // binSize else: nBins = nbins output.append((outZone, nBins)) return output, padRight
[docs] def compute_sub_matrix_wrapper(args): return heatmapper.compute_sub_matrix_worker(*args)
[docs] class heatmapper(object): """ Class to handle the reading and plotting of matrices. """ def __init__(self): self.parameters = None self.lengthDict = None self.matrix = None self.regions = None self.blackList = None self.quiet = True # These are parameters that were single values in versions <3 but are now internally lists. See issue #614 self.special_params = set(['unscaled 5 prime', 'unscaled 3 prime', 'body', 'downstream', 'upstream', 'ref point', 'bin size'])
[docs] def getTicks(self, idx): """ This is essentially a wrapper around getProfileTicks to accomdate the fact that each column has its own ticks. """ xticks, xtickslabel = getProfileTicks(self, self.reference_point_label[idx], self.startLabel, self.endLabel, idx) return xticks, xtickslabel
[docs] def computeMatrix(self, score_file_list, regions_file, parameters, blackListFileName=None, verbose=False, allArgs=None): """ Splits into multiple cores the computation of the scores per bin for each region (defined by a hash '#' in the regions (BED/GFF) file. """ if parameters['body'] > 0 and \ parameters['body'] % parameters['bin size'] > 0: exit("The --regionBodyLength has to be " "a multiple of --binSize.\nCurrently the " "values are {} {} for\nregionsBodyLength and " "binSize respectively\n".format(parameters['body'], parameters['bin size'])) # the beforeRegionStartLength is extended such that # length is a multiple of binSize if parameters['downstream'] % parameters['bin size'] > 0: exit("Length of region after the body has to be " "a multiple of --binSize.\nCurrent value " "is {}\n".format(parameters['downstream'])) if parameters['upstream'] % parameters['bin size'] > 0: exit("Length of region before the body has to be a multiple of " "--binSize\nCurrent value is {}\n".format(parameters['upstream'])) if parameters['unscaled 5 prime'] % parameters['bin size'] > 0: exit("Length of the unscaled 5 prime region has to be a multiple of " "--binSize\nCurrent value is {}\n".format(parameters['unscaled 5 prime'])) if parameters['unscaled 3 prime'] % parameters['bin size'] > 0: exit("Length of the unscaled 5 prime region has to be a multiple of " "--binSize\nCurrent value is {}\n".format(parameters['unscaled 3 prime'])) if parameters['unscaled 5 prime'] + parameters['unscaled 3 prime'] > 0 and parameters['body'] == 0: exit('Unscaled 5- and 3-prime regions only make sense with the scale-regions subcommand.\n') # Take care of GTF options transcriptID = "transcript" exonID = "exon" transcript_id_designator = "transcript_id" keepExons = False self.quiet = False if allArgs is not None: allArgs = vars(allArgs) transcriptID = allArgs.get("transcriptID", transcriptID) exonID = allArgs.get("exonID", exonID) transcript_id_designator = allArgs.get("transcript_id_designator", transcript_id_designator) keepExons = allArgs.get("keepExons", keepExons) self.quiet = allArgs.get("quiet", self.quiet) chromSizes, _ = getScorePerBigWigBin.getChromSizes(score_file_list) res, labels = mapReduce.mapReduce([score_file_list, parameters], compute_sub_matrix_wrapper, chromSizes, self_=self, bedFile=regions_file, blackListFileName=blackListFileName, numberOfProcessors=parameters['proc number'], includeLabels=True, transcriptID=transcriptID, exonID=exonID, transcript_id_designator=transcript_id_designator, keepExons=keepExons, verbose=verbose) # each worker in the pool returns a tuple containing # the submatrix data, the regions that correspond to the # submatrix, and the number of regions lacking scores # Since this is largely unsorted, we need to sort by group # merge all the submatrices into matrix matrix = np.concatenate([r[0] for r in res], axis=0) regions = [] regions_no_score = 0 for idx in range(len(res)): if len(res[idx][1]): regions.extend(res[idx][1]) regions_no_score += res[idx][2] groups = [x[3] for x in regions] foo = sorted(zip(groups, list(range(len(regions))), regions)) sortIdx = [x[1] for x in foo] regions = [x[2] for x in foo] matrix = matrix[sortIdx] # mask invalid (nan) values matrix = np.ma.masked_invalid(matrix) assert matrix.shape[0] == len(regions), \ "matrix length does not match regions length" if len(regions) == 0: sys.stderr.write("\nERROR: Either the BED file does not contain any valid regions or there are none remaining after filtering.\n") exit(1) if regions_no_score == len(regions): exit("\nERROR: None of the BED regions could be found in the bigWig" "file.\nPlease check that the bigwig file is valid and " "that the chromosome names between the BED file and " "the bigWig file correspond to each other\n") if regions_no_score > len(regions) * 0.75: file_type = 'bigwig' if score_file_list[0].endswith(".bw") else "BAM" prcnt = 100 * float(regions_no_score) / len(regions) sys.stderr.write( "\n\nWarning: {0:.2f}% of regions are *not* associated\n" "to any score in the given {1} file. Check that the\n" "chromosome names from the BED file are consistent with\n" "the chromosome names in the given {2} file and that both\n" "files refer to the same species\n\n".format(prcnt, file_type, file_type)) self.parameters = parameters numcols = matrix.shape[1] num_ind_cols = self.get_num_individual_matrix_cols() sample_boundaries = list(range(0, numcols + num_ind_cols, num_ind_cols)) if allArgs is not None and allArgs['samplesLabel'] is not None: sample_labels = allArgs['samplesLabel'] else: sample_labels = smartLabels(score_file_list) # Determine the group boundaries group_boundaries = [] group_labels_filtered = [] last_idx = -1 for x in range(len(regions)): if regions[x][3] != last_idx: last_idx = regions[x][3] group_boundaries.append(x) group_labels_filtered.append(labels[last_idx]) group_boundaries.append(len(regions)) # check if a given group is too small. Groups that # are too small can't be plotted and an exception is thrown. group_len = np.diff(group_boundaries) if len(group_len) > 1: sum_len = sum(group_len) group_frac = [float(x) / sum_len for x in group_len] if min(group_frac) <= 0.002: sys.stderr.write( "One of the groups defined in the bed file is " "too small.\nGroups that are too small can't be plotted. " "\n") self.matrix = _matrix(regions, matrix, group_boundaries, sample_boundaries, group_labels_filtered, sample_labels) if parameters['skip zeros']: self.matrix.removeempty()
[docs] @staticmethod def compute_sub_matrix_worker(self, chrom, start, end, score_file_list, parameters, regions): """ Returns ------- numpy matrix A numpy matrix that contains per each row the values found per each of the regions given """ if parameters['verbose']: sys.stderr.write("Processing {}:{}-{}\n".format(chrom, start, end)) # read BAM or scores file score_file_handles = [] for sc_file in score_file_list: score_file_handles.append(pyBigWig.open(sc_file)) # determine the number of matrix columns based on the lengths # given by the user, times the number of score files matrix_cols = len(score_file_list) * \ ((parameters['downstream'] + parameters['unscaled 5 prime'] + parameters['unscaled 3 prime'] + parameters['upstream'] + parameters['body']) // parameters['bin size']) # create an empty matrix to store the values sub_matrix = np.zeros((len(regions), matrix_cols)) sub_matrix[:] = np.NAN j = 0 sub_regions = [] regions_no_score = 0 for transcript in regions: feature_chrom = transcript[0] exons = transcript[1] feature_start = exons[0][0] feature_end = exons[-1][1] feature_name = transcript[2] feature_strand = transcript[4] padLeft = 0 padRight = 0 padLeftNaN = 0 padRightNaN = 0 upstream = [] downstream = [] # get the body length body_length = np.sum([x[1] - x[0] for x in exons]) - parameters['unscaled 5 prime'] - parameters['unscaled 3 prime'] # print some information if parameters['body'] > 0 and \ body_length < parameters['bin size']: if not self.quiet: sys.stderr.write("A region that is shorter than the bin size (possibly only after accounting for unscaled regions) was found: " "({0}) {1} {2}:{3}:{4}. Skipping...\n".format((body_length - parameters['unscaled 5 prime'] - parameters['unscaled 3 prime']), feature_name, feature_chrom, feature_start, feature_end)) coverage = np.zeros(matrix_cols) if not parameters['missing data as zero']: coverage[:] = np.nan else: if feature_strand == '-': if parameters['downstream'] > 0: upstream = [(feature_start - parameters['downstream'], feature_start)] if parameters['upstream'] > 0: downstream = [(feature_end, feature_end + parameters['upstream'])] unscaled5prime, body, unscaled3prime, padLeft, padRight = chopRegions(exons, left=parameters['unscaled 3 prime'], right=parameters['unscaled 5 prime']) # bins per zone a = parameters['downstream'] // parameters['bin size'] b = parameters['unscaled 3 prime'] // parameters['bin size'] d = parameters['unscaled 5 prime'] // parameters['bin size'] e = parameters['upstream'] // parameters['bin size'] else: if parameters['upstream'] > 0: upstream = [(feature_start - parameters['upstream'], feature_start)] if parameters['downstream'] > 0: downstream = [(feature_end, feature_end + parameters['downstream'])] unscaled5prime, body, unscaled3prime, padLeft, padRight = chopRegions(exons, left=parameters['unscaled 5 prime'], right=parameters['unscaled 3 prime']) a = parameters['upstream'] // parameters['bin size'] b = parameters['unscaled 5 prime'] // parameters['bin size'] d = parameters['unscaled 3 prime'] // parameters['bin size'] e = parameters['downstream'] // parameters['bin size'] c = parameters['body'] // parameters['bin size'] # build zones (each is a list of tuples) # zone0: region before the region start, # zone1: unscaled 5 prime region # zone2: the body of the region # zone3: unscaled 3 prime region # zone4: the region from the end of the region downstream # the format for each zone is: [(start, end), ...], number of bins # Note that for "reference-point", upstream/downstream will go # through the exons (if requested) and then possibly continue # on the other side (unless parameters['nan after end'] is true) if parameters['body'] > 0: zones = [(upstream, a), (unscaled5prime, b), (body, c), (unscaled3prime, d), (downstream, e)] elif parameters['ref point'] == 'TES': # around TES if feature_strand == '-': downstream, body, unscaled3prime, padRight, _ = chopRegions(exons, left=parameters['upstream']) if padRight > 0 and parameters['nan after end'] is True: padRightNaN += padRight elif padRight > 0: downstream.append((downstream[-1][1], downstream[-1][1] + padRight)) padRight = 0 else: unscale5prime, body, upstream, _, padLeft = chopRegions(exons, right=parameters['upstream']) if padLeft > 0 and parameters['nan after end'] is True: padLeftNaN += padLeft elif padLeft > 0: upstream.insert(0, (upstream[0][0] - padLeft, upstream[0][0])) padLeft = 0 e = np.sum([x[1] - x[0] for x in downstream]) // parameters['bin size'] a = np.sum([x[1] - x[0] for x in upstream]) // parameters['bin size'] zones = [(upstream, a), (downstream, e)] elif parameters['ref point'] == 'center': # at the region center if feature_strand == '-': upstream, downstream, padLeft, padRight = chopRegionsFromMiddle(exons, left=parameters['downstream'], right=parameters['upstream']) else: upstream, downstream, padLeft, padRight = chopRegionsFromMiddle(exons, left=parameters['upstream'], right=parameters['downstream']) if padLeft > 0 and parameters['nan after end'] is True: padLeftNaN += padLeft elif padLeft > 0: if len(upstream) > 0: upstream.insert(0, (upstream[0][0] - padLeft, upstream[0][0])) else: upstream = [(downstream[0][0] - padLeft, downstream[0][0])] padLeft = 0 if padRight > 0 and parameters['nan after end'] is True: padRightNaN += padRight elif padRight > 0: downstream.append((downstream[-1][1], downstream[-1][1] + padRight)) padRight = 0 a = np.sum([x[1] - x[0] for x in upstream]) // parameters['bin size'] e = np.sum([x[1] - x[0] for x in downstream]) // parameters['bin size'] # It's possible for a/e to be floats or 0 yet upstream/downstream isn't empty if a < 1: upstream = [] a = 0 if e < 1: downstream = [] e = 0 zones = [(upstream, a), (downstream, e)] else: # around TSS if feature_strand == '-': unscale5prime, body, upstream, _, padLeft = chopRegions(exons, right=parameters['downstream']) if padLeft > 0 and parameters['nan after end'] is True: padLeftNaN += padLeft elif padLeft > 0: upstream.insert(0, (upstream[0][0] - padLeft, upstream[0][0])) padLeft = 0 else: downstream, body, unscaled3prime, padRight, _ = chopRegions(exons, left=parameters['downstream']) if padRight > 0 and parameters['nan after end'] is True: padRightNaN += padRight elif padRight > 0: downstream.append((downstream[-1][1], downstream[-1][1] + padRight)) padRight = 0 a = np.sum([x[1] - x[0] for x in upstream]) // parameters['bin size'] e = np.sum([x[1] - x[0] for x in downstream]) // parameters['bin size'] zones = [(upstream, a), (downstream, e)] foo = parameters['upstream'] bar = parameters['downstream'] if feature_strand == '-': foo, bar = bar, foo if padLeftNaN > 0: expected = foo // parameters['bin size'] padLeftNaN = int(round(float(padLeftNaN) / parameters['bin size'])) if expected - padLeftNaN - a > 0: padLeftNaN += 1 if padRightNaN > 0: expected = bar // parameters['bin size'] padRightNaN = int(round(float(padRightNaN) / parameters['bin size'])) if expected - padRightNaN - e > 0: padRightNaN += 1 coverage = [] # compute the values for each of the files being processed. # "cov" is a numpy array of bins for sc_handler in score_file_handles: # We're only supporting bigWig files at this point cov = heatmapper.coverage_from_big_wig( sc_handler, feature_chrom, zones, parameters['bin size'], parameters['bin avg type'], parameters['missing data as zero'], not self.quiet) if padLeftNaN > 0: cov = np.concatenate([[np.nan] * padLeftNaN, cov]) if padRightNaN > 0: cov = np.concatenate([cov, [np.nan] * padRightNaN]) if feature_strand == "-": cov = cov[::-1] coverage = np.hstack([coverage, cov]) if coverage is None: regions_no_score += 1 if not self.quiet: sys.stderr.write( "No data was found for region " "{0} {1}:{2}-{3}. Skipping...\n".format( feature_name, feature_chrom, feature_start, feature_end)) coverage = np.zeros(matrix_cols) if not parameters['missing data as zero']: coverage[:] = np.nan try: temp = coverage.copy() temp[np.isnan(temp)] = 0 except: if not self.quiet: sys.stderr.write( "No scores defined for region " "{0} {1}:{2}-{3}. Skipping...\n".format(feature_name, feature_chrom, feature_start, feature_end)) coverage = np.zeros(matrix_cols) if not parameters['missing data as zero']: coverage[:] = np.nan if parameters['min threshold'] is not None and coverage.min() <= parameters['min threshold']: continue if parameters['max threshold'] is not None and coverage.max() >= parameters['max threshold']: continue if parameters['scale'] != 1: coverage = parameters['scale'] * coverage sub_matrix[j, :] = coverage sub_regions.append(transcript) j += 1 # remove empty rows sub_matrix = sub_matrix[0:j, :] if len(sub_regions) != len(sub_matrix[:, 0]): sys.stderr.write("regions lengths do not match\n") return sub_matrix, sub_regions, regions_no_score
[docs] @staticmethod def coverage_from_array(valuesArray, zones, binSize, avgType): try: valuesArray[0] except (IndexError, TypeError) as detail: sys.stderr.write("{0}\nvalues array value: {1}, zones {2}\n".format(detail, valuesArray, zones)) cvglist = [] zoneEnd = 0 valStart = 0 valEnd = 0 for zone, nBins in zones: if nBins: # linspace is used to more or less evenly partition the data points into the given number of bins zoneEnd += nBins valStart = valEnd valEnd += np.sum([x[1] - x[0] for x in zone]) counts_list = [] # Partition the space into bins if nBins == 1: pos_array = np.array([valStart]) else: pos_array = np.linspace(valStart, valEnd, nBins, endpoint=False, dtype=int) pos_array = np.append(pos_array, valEnd) idx = 0 while idx < nBins: idxStart = int(pos_array[idx]) idxEnd = max(int(pos_array[idx + 1]), idxStart + 1) try: counts_list.append(heatmapper.my_average(valuesArray[idxStart:idxEnd], avgType)) except Exception as detail: sys.stderr.write("Exception found: {0}\n".format(detail)) idx += 1 cvglist.append(np.array(counts_list)) return np.concatenate(cvglist)
[docs] @staticmethod def change_chrom_names(chrom): """ Changes UCSC chromosome names to ensembl chromosome names and vice versa. """ if chrom.startswith('chr'): # remove the chr part from chromosome name chrom = chrom[3:] if chrom == "M": chrom = "MT" else: # prefix with 'chr' the chromosome name chrom = 'chr' + chrom if chrom == "chrMT": chrom = "chrM" return chrom
[docs] @staticmethod def coverage_from_big_wig(bigwig, chrom, zones, binSize, avgType, nansAsZeros=False, verbose=True): """ uses pyBigWig to query a region define by chrom and zones. The output is an array that contains the bigwig value per base pair. The summary over bins is done in a later step when coverage_from_array is called. This method is more reliable than querying the bins directly from the bigwig, which should be more efficient. By default, any region, even if no chromosome match is found on the bigwig file, produces a result. In other words no regions are skipped. zones: array as follows zone0: region before the region start, zone1: 5' unscaled region (if present) zone2: the body of the region (not always present) zone3: 3' unscaled region (if present) zone4: the region from the end of the region downstream each zone is a tuple containing start, end, and number of bins This is useful if several matrices wants to be merged or if the sorted BED output of one computeMatrix operation needs to be used for other cases """ nVals = 0 for zone, _ in zones: for region in zone: nVals += region[1] - region[0] values_array = np.zeros(nVals) if not nansAsZeros: values_array[:] = np.nan if chrom not in list(bigwig.chroms().keys()): unmod_name = chrom chrom = heatmapper.change_chrom_names(chrom) if chrom not in list(bigwig.chroms().keys()): if verbose: sys.stderr.write("Warning: Your chromosome names do not match.\nPlease check that the " "chromosome names in your BED file\ncorrespond to the names in your " "bigWig file.\nAn empty line will be added to your heatmap.\nThe problematic " "chromosome name is {0}\n\n".format(unmod_name)) # return empty nan array return heatmapper.coverage_from_array(values_array, zones, binSize, avgType) maxLen = bigwig.chroms(chrom) startIdx = 0 endIdx = 0 for zone, _ in zones: for region in zone: startIdx = endIdx if region[0] < 0: endIdx += abs(region[0]) values_array[startIdx:endIdx] = np.nan startIdx = endIdx start = max(0, region[0]) end = min(maxLen, region[1]) endIdx += end - start if start < end: # This won't be the case if we extend off the front of a chromosome, such as (-100, 0) values_array[startIdx:endIdx] = bigwig.values(chrom, start, end) if end < region[1]: startIdx = endIdx endIdx += region[1] - end values_array[startIdx:endIdx] = np.nan # replaces nans for zeros if nansAsZeros: values_array[np.isnan(values_array)] = 0 return heatmapper.coverage_from_array(values_array, zones, binSize, avgType)
[docs] @staticmethod def my_average(valuesArray, avgType='mean'): """ computes the mean, median, etc but only for those values that are not Nan """ valuesArray = np.ma.masked_invalid(valuesArray) avg = np.ma.__getattribute__(avgType)(valuesArray) if isinstance(avg, np.ma.core.MaskedConstant): return np.nan else: return avg
[docs] def matrix_from_dict(self, matrixDict, regionsDict, parameters): self.regionsDict = regionsDict self.matrixDict = matrixDict self.parameters = parameters self.lengthDict = OrderedDict() self.matrixAvgsDict = OrderedDict()
[docs] def read_matrix_file(self, matrix_file): # reads a bed file containing the position # of genomic intervals # In case a hash sign '#' is found in the # file, this is considered as a delimiter # to split the heatmap into groups import json regions = [] matrix_rows = [] current_group_index = 0 max_group_bound = None fh = gzip.open(matrix_file) for line in fh: line = toString(line).strip() # read the header file containing the parameters # used if line.startswith("@"): # the parameters used are saved using # json self.parameters = json.loads(line[1:].strip()) max_group_bound = self.parameters['group_boundaries'][1] continue # split the line into bed interval and matrix values region = line.split('\t') chrom, start, end, name, score, strand = region[0:6] matrix_row = np.ma.masked_invalid(np.fromiter(region[6:], float)) matrix_rows.append(matrix_row) starts = start.split(",") ends = end.split(",") regs = [(int(x), int(y)) for x, y in zip(starts, ends)] # get the group index if len(regions) >= max_group_bound: current_group_index += 1 max_group_bound = self.parameters['group_boundaries'][current_group_index + 1] regions.append([chrom, regs, name, max_group_bound, strand, score]) matrix = np.vstack(matrix_rows) self.matrix = _matrix(regions, matrix, self.parameters['group_boundaries'], self.parameters['sample_boundaries'], group_labels=self.parameters['group_labels'], sample_labels=self.parameters['sample_labels']) if 'sort regions' in self.parameters: self.matrix.set_sorting_method(self.parameters['sort regions'], self.parameters['sort using']) # Versions of computeMatrix before 3.0 didn't have an entry of these per column, fix that nSamples = len(self.matrix.sample_labels) h = dict() for k, v in self.parameters.items(): if k in self.special_params and type(v) is not list: v = [v] * nSamples if len(v) == 0: v = [None] * nSamples h[k] = v self.parameters = h return
[docs] def save_matrix(self, file_name): """ saves the data required to reconstruct the matrix the format is: A header containing the parameters used to create the matrix encoded as: @key:value\tkey2:value2 etc... The rest of the file has the same first 5 columns of a BED file: chromosome name, start, end, name, score and strand, all separated by tabs. After the fifth column the matrix values are appended separated by tabs. Groups are separated by adding a line starting with a hash (#) and followed by the group name. The file is gzipped. """ import json self.parameters['sample_labels'] = self.matrix.sample_labels self.parameters['group_labels'] = self.matrix.group_labels self.parameters['sample_boundaries'] = self.matrix.sample_boundaries self.parameters['group_boundaries'] = self.matrix.group_boundaries # Redo the parameters, ensuring things related to ticks and labels are repeated appropriately nSamples = len(self.matrix.sample_labels) h = dict() for k, v in self.parameters.items(): if type(v) is list and len(v) == 0: v = None if k in self.special_params and type(v) is not list: v = [v] * nSamples if len(v) == 0: v = [None] * nSamples h[k] = v fh = gzip.open(file_name, 'wb') params_str = json.dumps(h, separators=(',', ':')) fh.write(toBytes("@" + params_str + "\n")) score_list = np.ma.masked_invalid(np.mean(self.matrix.matrix, axis=1)) for idx, region in enumerate(self.matrix.regions): # join np_array values # keeping nans while converting them to strings if not np.ma.is_masked(score_list[idx]): float(score_list[idx]) matrix_values = "\t".join( np.char.mod('%f', self.matrix.matrix[idx, :])) starts = ["{0}".format(x[0]) for x in region[1]] ends = ["{0}".format(x[1]) for x in region[1]] starts = ",".join(starts) ends = ",".join(ends) # BEDish format (we don't currently store the score) fh.write( toBytes('{0}\t{1}\t{2}\t{3}\t{4}\t{5}\t{6}\n'.format( region[0], starts, ends, region[2], region[5], region[4], matrix_values))) fh.close()
[docs] def save_tabulated_values(self, file_handle, reference_point_label='TSS', start_label='TSS', end_label='TES', averagetype='mean'): """ Saves the values averaged by col using the avg_type given Args: file_handle: file name to save the file reference_point_label: Name of the reference point label start_label: Name of the star label end_label: Name of the end label averagetype: average type (e.g. mean, median, std) """ # get X labels w = self.parameters['bin size'] b = self.parameters['upstream'] a = self.parameters['downstream'] c = self.parameters.get('unscaled 5 prime', 0) d = self.parameters.get('unscaled 3 prime', 0) m = self.parameters['body'] xticks = [] xtickslabel = [] for idx in range(self.matrix.get_num_samples()): if b[idx] < 1e5: quotient = 1000 symbol = 'Kb' else: quotient = 1e6 symbol = 'Mb' if m[idx] == 0: last = 0 if len(xticks): last = xticks[-1] xticks.extend([last + (k / w[idx]) for k in [w[idx], b[idx], b[idx] + a[idx]]]) xtickslabel.extend(['{0:.1f}{1}'.format(-(float(b[idx]) / quotient), symbol), reference_point_label, '{0:.1f}{1}'.format(float(a[idx]) / quotient, symbol)]) else: xticks_values = [w[idx]] # only if upstream region is set, add a x tick if b[idx] > 0: xticks_values.append(b[idx]) xtickslabel.append('{0:.1f}{1}'.format(-(float(b[idx]) / quotient), symbol)) xtickslabel.append(start_label) if c[idx] > 0: xticks_values.append(b[idx] + c[idx]) xtickslabel.append("") if d[idx] > 0: xticks_values.append(b[idx] + c[idx] + m[idx]) xtickslabel.append("") xticks_values.append(b[idx] + c[idx] + m[idx] + d[idx]) xtickslabel.append(end_label) if a[idx] > 0: xticks_values.append(b[idx] + c[idx] + m[idx] + d[idx] + a[idx]) xtickslabel.append('{0:.1f}{1}'.format(float(a[idx]) / quotient, symbol)) last = 0 if len(xticks): last = xticks[-1] xticks.extend([last + (k / w[idx]) for k in xticks_values]) x_axis = np.arange(xticks[-1]) + 1 labs = [] for x_value in x_axis: if x_value in xticks and xtickslabel[xticks.index(x_value)]: labs.append(xtickslabel[xticks.index(x_value)]) elif x_value in xticks: labs.append("tick") else: labs.append("") with open(file_handle, 'w') as fh: # write labels fh.write("bin labels\t\t{}\n".format("\t".join(labs))) fh.write('bins\t\t{}\n'.format("\t".join([str(x) for x in x_axis]))) for sample_idx in range(self.matrix.get_num_samples()): for group_idx in range(self.matrix.get_num_groups()): sub_matrix = self.matrix.get_matrix(group_idx, sample_idx) values = [str(x) for x in np.ma.__getattribute__(averagetype)(sub_matrix['matrix'], axis=0)] fh.write("{}\t{}\t{}\n".format(sub_matrix['sample'], sub_matrix['group'], "\t".join(values)))
[docs] def save_matrix_values(self, file_name): # print a header telling the group names and their length fh = open(file_name, 'wb') info = [] groups_len = np.diff(self.matrix.group_boundaries) for i in range(len(self.matrix.group_labels)): info.append("{}:{}".format(self.matrix.group_labels[i], groups_len[i])) fh.write(toBytes("#{}\n".format("\t".join(info)))) # add to header the x axis values fh.write(toBytes("#downstream:{}\tupstream:{}\tbody:{}\tbin size:{}\tunscaled 5 prime:{}\tunscaled 3 prime:{}\n".format( self.parameters['downstream'], self.parameters['upstream'], self.parameters['body'], self.parameters['bin size'], self.parameters.get('unscaled 5 prime', 0), self.parameters.get('unscaled 3 prime', 0)))) sample_len = np.diff(self.matrix.sample_boundaries) for i in range(len(self.matrix.sample_labels)): info.extend([self.matrix.sample_labels[i]] * sample_len[i]) fh.write(toBytes("{}\n".format("\t".join(info)))) fh.close() # reopen again using append mode fh = open(file_name, 'ab') np.savetxt(fh, self.matrix.matrix, fmt="%.4g", delimiter="\t") fh.close()
[docs] def save_BED(self, file_handle): boundaries = np.array(self.matrix.group_boundaries) # Add a header file_handle.write("#chrom\tstart\tend\tname\tscore\tstrand\tthickStart\tthickEnd\titemRGB\tblockCount\tblockSizes\tblockStart\tdeepTools_group") if self.matrix.silhouette is not None: file_handle.write("\tsilhouette") file_handle.write("\n") for idx, region in enumerate(self.matrix.regions): # the label id corresponds to the last boundary # that is smaller than the region index. # for example for a boundary array = [0, 10, 20] # and labels ['a', 'b', 'c'], # for index 5, the label is 'a', for # index 10, the label is 'b' etc label_idx = np.flatnonzero(boundaries <= idx)[-1] starts = ["{0}".format(x[0]) for x in region[1]] ends = ["{0}".format(x[1]) for x in region[1]] starts = ",".join(starts) ends = ",".join(ends) file_handle.write( '{0}\t{1}\t{2}\t{3}\t{4}\t{5}\t{1}\t{2}\t0'.format( region[0], region[1][0][0], region[1][-1][1], region[2], region[5], region[4])) file_handle.write( '\t{0}\t{1}\t{2}\t{3}'.format( len(region[1]), ",".join([str(int(y) - int(x)) for x, y in region[1]]), ",".join([str(int(x) - int(starts[0])) for x, y in region[1]]), self.matrix.group_labels[label_idx])) if self.matrix.silhouette is not None: file_handle.write("\t{}".format(self.matrix.silhouette[idx])) file_handle.write("\n") file_handle.close()
[docs] @staticmethod def matrix_avg(matrix, avgType='mean'): matrix = np.ma.masked_invalid(matrix) return np.ma.__getattribute__(avgType)(matrix, axis=0)
[docs] def get_individual_matrices(self, matrix): """In case multiple matrices are saved one after the other this method splits them appart. Returns a list containing the matrices """ num_cols = matrix.shape[1] num_ind_cols = self.get_num_individual_matrix_cols() matrices_list = [] for i in range(0, num_cols, num_ind_cols): if i + num_ind_cols > num_cols: break matrices_list.append(matrix[:, i:i + num_ind_cols]) return matrices_list
[docs] def get_num_individual_matrix_cols(self): """ returns the number of columns that each matrix should have. This is done because the final matrix that is plotted can be composed of smaller matrices that are merged one after the other. """ matrixCols = ((self.parameters['downstream'] + self.parameters['upstream'] + self.parameters['body'] + self.parameters['unscaled 5 prime'] + self.parameters['unscaled 3 prime']) // self.parameters['bin size']) return matrixCols
[docs] def computeSilhouetteScore(d, idx, labels): """ Given a square distance matrix with NaN diagonals, compute the silhouette score of a given row (idx). Each row should have an associated label (labels). """ keep = ~np.isnan(d[idx, ]) foo = np.bincount(labels[keep], weights=d[idx, ][keep]) groupSizes = np.bincount(labels[keep]) intraIdx = labels[idx] if groupSizes[intraIdx] == 1: return 0 intra = foo[labels[idx]] / groupSizes[intraIdx] interMask = np.arange(len(foo))[np.arange(len(foo)) != labels[idx]] inter = np.min(foo[interMask] / groupSizes[interMask]) return (inter - intra) / max(inter, intra)
class _matrix(object): """ class to hold heatmapper matrices The base data is a large matrix with definition to know the boundaries for row and col divisions. Col divisions represent groups within a subset, e.g. Active and inactive from PolII bigwig data. Row division represent different samples, for example PolII in males vs. PolII in females. This is an internal class of the heatmapper class """ def __init__(self, regions, matrix, group_boundaries, sample_boundaries, group_labels=None, sample_labels=None): # simple checks assert matrix.shape[0] == group_boundaries[-1], \ "row max do not match matrix shape" assert matrix.shape[1] == sample_boundaries[-1], \ "col max do not match matrix shape" self.regions = regions self.matrix = matrix self.group_boundaries = group_boundaries self.sample_boundaries = sample_boundaries self.sort_method = None self.sort_using = None self.silhouette = None if group_labels is None: self.group_labels = ['group {}'.format(x) for x in range(len(group_boundaries) - 1)] else: assert len(group_labels) == len(group_boundaries) - 1, \ "number of group labels does not match number of groups" self.group_labels = group_labels if sample_labels is None: self.sample_labels = ['sample {}'.format(x) for x in range(len(sample_boundaries) - 1)] else: assert len(sample_labels) == len(sample_boundaries) - 1, \ "number of sample labels does not match number of samples" self.sample_labels = sample_labels def get_matrix(self, group, sample): """ Returns a sub matrix from the large matrix. Group and sample are ids, thus, row = 0, col=0 get the first group of the first sample. Returns ------- dictionary containing the matrix, the group label and the sample label """ group_start = self.group_boundaries[group] group_end = self.group_boundaries[group + 1] sample_start = self.sample_boundaries[sample] sample_end = self.sample_boundaries[sample + 1] return {'matrix': np.ma.masked_invalid(self.matrix[group_start:group_end, :][:, sample_start:sample_end]), 'group': self.group_labels[group], 'sample': self.sample_labels[sample]} def get_num_samples(self): return len(self.sample_labels) def get_num_groups(self): return len(self.group_labels) def set_group_labels(self, new_labels): """ sets new labels for groups """ if len(new_labels) != len(self.group_labels): raise ValueError("length new labels != length original labels") self.group_labels = new_labels def set_sample_labels(self, new_labels): """ sets new labels for groups """ if len(new_labels) != len(self.sample_labels): raise ValueError("length new labels != length original labels") self.sample_labels = new_labels def set_sorting_method(self, sort_method, sort_using): self.sort_method = sort_method self.sort_using = sort_using def get_regions(self): """Returns the regions per group Returns ------ list Each element of the list is itself a list of dictionaries containing the regions info: chrom, start, end, strand, name etc. Each element of the list corresponds to each of the groups """ regions = [] for idx in range(len(self.group_labels)): start = self.group_boundaries[idx] end = self.group_boundaries[idx + 1] regions.append(self.regions[start:end]) return regions def sort_groups(self, sort_using='mean', sort_method='no', sample_list=None): """ Sorts and rearranges the submatrices according to the sorting method given. """ if sort_method == 'no': return if (sample_list is not None) and (len(sample_list) > 0): # get the ids that correspond to the selected sample list idx_to_keep = [] for sample_idx in sample_list: idx_to_keep += range(self.sample_boundaries[sample_idx], self.sample_boundaries[sample_idx + 1]) matrix = self.matrix[:, idx_to_keep] else: matrix = self.matrix # compute the row average: if sort_using == 'region_length': matrix_avgs = list() for x in self.regions: matrix_avgs.append(np.sum([bar[1] - bar[0] for bar in x[1]])) matrix_avgs = np.array(matrix_avgs) elif sort_using == 'mean': matrix_avgs = np.nanmean(matrix, axis=1) elif sort_using == 'mean': matrix_avgs = np.nanmean(matrix, axis=1) elif sort_using == 'median': matrix_avgs = np.nanmedian(matrix, axis=1) elif sort_using == 'max': matrix_avgs = np.nanmax(matrix, axis=1) elif sort_using == 'min': matrix_avgs = np.nanmin(matrix, axis=1) elif sort_using == 'sum': matrix_avgs = np.nansum(matrix, axis=1) else: sys.exit("{} is an unsupported sorting method".format(sort_using)) # order per group _sorted_regions = [] _sorted_matrix = [] for idx in range(len(self.group_labels)): start = self.group_boundaries[idx] end = self.group_boundaries[idx + 1] order = matrix_avgs[start:end].argsort() if sort_method == 'descend': order = order[::-1] _sorted_matrix.append(self.matrix[start:end, :][order, :]) # sort the regions _reg = self.regions[start:end] for idx in order: _sorted_regions.append(_reg[idx]) self.matrix = np.vstack(_sorted_matrix) self.regions = _sorted_regions self.set_sorting_method(sort_method, sort_using) def hmcluster(self, k, evaluate_silhouette=True, method='kmeans', clustering_samples=None): matrix = np.asarray(self.matrix) matrix_to_cluster = matrix if clustering_samples is not None: assert all(i > 0 for i in clustering_samples), \ "all indices should be bigger than or equal to 1." assert all(i <= len(self.sample_labels) for i in clustering_samples), \ "each index should be smaller than or equal to {}(total "\ "number of samples.)".format(len(self.sample_labels)) clustering_samples = np.asarray(clustering_samples) - 1 samples_cols = [] for idx in clustering_samples: samples_cols += range(self.sample_boundaries[idx], self.sample_boundaries[idx + 1]) matrix_to_cluster = matrix_to_cluster[:, samples_cols] if np.any(np.isnan(matrix_to_cluster)): # replace nans for 0 otherwise kmeans produces a weird behaviour sys.stderr.write("*Warning* For clustering nan values have to be replaced by zeros \n") matrix_to_cluster[np.isnan(matrix_to_cluster)] = 0 if method == 'kmeans': from scipy.cluster.vq import vq, kmeans centroids, _ = kmeans(matrix_to_cluster, k) # order the centroids in an attempt to # get the same cluster order cluster_labels, _ = vq(matrix_to_cluster, centroids) if method == 'hierarchical': # normally too slow for large data sets from scipy.cluster.hierarchy import fcluster, linkage Z = linkage(matrix_to_cluster, method='ward', metric='euclidean') cluster_labels = fcluster(Z, k, criterion='maxclust') # hierarchical clustering labels from 1 .. k # while k-means labels 0 .. k -1 # Thus, for consistency, we subtract 1 cluster_labels -= 1 # sort clusters _clustered_mean = [] _cluster_ids_list = [] for cluster in range(k): cluster_ids = np.flatnonzero(cluster_labels == cluster) _cluster_ids_list.append(cluster_ids) _clustered_mean.append(matrix_to_cluster[cluster_ids, :].mean()) # reorder clusters based on mean cluster_order = np.argsort(_clustered_mean)[::-1] # create groups using the clustering self.group_labels = [] self.group_boundaries = [0] _clustered_regions = [] _clustered_matrix = [] cluster_number = 1 for cluster in cluster_order: self.group_labels.append("cluster_{}".format(cluster_number)) cluster_number += 1 cluster_ids = _cluster_ids_list[cluster] self.group_boundaries.append(self.group_boundaries[-1] + len(cluster_ids)) _clustered_matrix.append(self.matrix[cluster_ids, :]) for idx in cluster_ids: _clustered_regions.append(self.regions[idx]) self.regions = _clustered_regions self.matrix = np.vstack(_clustered_matrix) return idx def computeSilhouette(self, k): if k > 1: from scipy.spatial.distance import pdist, squareform silhouette = np.repeat(0.0, self.group_boundaries[-1]) groupSizes = np.subtract(self.group_boundaries[1:], self.group_boundaries[:-1]) labels = np.repeat(np.arange(k), groupSizes) d = pdist(self.matrix) d2 = squareform(d) np.fill_diagonal(d2, np.nan) # This excludes the diagonal for idx in range(len(labels)): silhouette[idx] = computeSilhouetteScore(d2, idx, labels) sys.stderr.write("The average silhouette score is: {}\n".format(np.mean(silhouette))) self.silhouette = silhouette def removeempty(self): """ removes matrix rows containing only zeros or nans """ to_keep = [] score_list = np.ma.masked_invalid(np.mean(self.matrix, axis=1)) for idx, region in enumerate(self.regions): if np.ma.is_masked(score_list[idx]) or float(score_list[idx]) == 0: continue else: to_keep.append(idx) self.regions = [self.regions[x] for x in to_keep] self.matrix = self.matrix[to_keep, :] # adjust sample boundaries to_keep = np.array(to_keep) self.group_boundaries = [len(to_keep[to_keep < x]) for x in self.group_boundaries] def flatten(self): """ flatten and remove nans from matrix. Useful to get max and mins from matrix. :return flattened matrix """ matrix_flatten = np.asarray(self.matrix.flatten()) # nans are removed from the flattened array matrix_flatten = matrix_flatten[~np.isnan(matrix_flatten)] if len(matrix_flatten) == 0: num_nan = len(np.flatnonzero(np.isnan(self.matrix.flatten()))) raise ValueError("matrix only contains nans " "(total nans: {})".format(num_nan)) return matrix_flatten