comparison src/breadcrumbs/src/Metric.py @ 0:2f4f6f08c8c4 draft

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1 """
2 Author: Timothy Tickle
3 Description: Calculates Metrics.
4 """
5
6 #####################################################################################
7 #Copyright (C) <2012>
8 #
9 #Permission is hereby granted, free of charge, to any person obtaining a copy of
10 #this software and associated documentation files (the "Software"), to deal in the
11 #Software without restriction, including without limitation the rights to use, copy,
12 #modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
13 #and to permit persons to whom the Software is furnished to do so, subject to
14 #the following conditions:
15 #
16 #The above copyright notice and this permission notice shall be included in all copies
17 #or substantial portions of the Software.
18 #
19 #THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
20 #INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
21 #PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
22 #HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 #OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 #SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 #####################################################################################
26
27 __author__ = "Timothy Tickle"
28 __copyright__ = "Copyright 2012"
29 __credits__ = ["Timothy Tickle"]
30 __license__ = "MIT"
31 __maintainer__ = "Timothy Tickle"
32 __email__ = "ttickle@sph.harvard.edu"
33 __status__ = "Development"
34
35 #Update path
36 from ConstantsBreadCrumbs import ConstantsBreadCrumbs
37 import csv
38 import numpy as np
39 from types import *
40 from ValidateData import ValidateData
41
42 #External libraries
43 from cogent.maths.unifrac.fast_unifrac import fast_unifrac_file
44 import cogent.maths.stats.alpha_diversity
45 import scipy.spatial.distance
46
47 class Metric:
48 """
49 Performs ecological measurements.
50 """
51
52 #Diversity metrics Alpha
53 c_strSimpsonDiversity = "SimpsonD"
54 c_strInvSimpsonDiversity = "InSimpsonD"
55 c_strChao1Diversity = "Chao1"
56
57 #Diversity metrics Beta
58 c_strBrayCurtisDissimilarity = "B_Curtis"
59 c_strUnifracUnweighted = "unifrac_unweighted"
60 c_strUnifracWeighted = "unifrac_weighted"
61
62 #Additive inverses of beta metrics
63 c_strInvBrayCurtisDissimilarity = "InB_Curtis"
64
65 #Richness
66 c_strShannonRichness = "ShannonR"
67 c_strObservedCount = "Observed_Count"
68
69 #Different alpha diversity metrics
70 setAlphaDiversities = set(["observed_species","margalef","menhinick",
71 "dominance","reciprocal_simpson","shannon","equitability","berger_parker_d",
72 "mcintosh_d","brillouin_d","strong","fisher_alpha","simpson",
73 "mcintosh_e","heip_e","simpson_e","robbins","michaelis_menten_fit","chao1","ACE"])
74
75 #Different beta diversity metrics
76 setBetaDiversities = set(["braycurtis","canberra","chebyshev","cityblock",
77 "correlation","cosine","euclidean","hamming","sqeuclidean"])
78
79 #Tested 4
80 @staticmethod
81 def funcGetSimpsonsDiversityIndex(ldSampleTaxaAbundancies=None):
82 """
83 Calculates the Simpsons diversity index as defined as sum(Pi*Pi).
84 Note***: Assumes that the abundance measurements are already normalized by the total population N.
85
86 :param ldSampleTaxaAbundancies: List of measurements to calculate metric on (a sample).
87 :type: List of doubles
88 :return Double: Diversity metric
89 """
90
91 #Calculate metric
92 return sum((ldSampleTaxaAbundancies)*(ldSampleTaxaAbundancies))
93
94 #Tested 4
95 @staticmethod
96 def funcGetInverseSimpsonsDiversityIndex(ldSampleTaxaAbundancies=None):
97 """
98 Calculates Inverse Simpsons diversity index 1/sum(Pi*Pi).
99 This is multiplicative inverse which reverses the order of the simpsons diversity index.
100 Note***: Assumes that the abundance measurements are already normalized by the total population N.
101
102 :param ldSampleTaxaAbundancies: List of measurements to calculate metric on (a sample).
103 :type: List of doubles
104 :return Double: Diversity metric
105 """
106
107 simpsons = Metric.funcGetSimpsonsDiversityIndex(ldSampleTaxaAbundancies)
108 #If simpsons is false return false, else return inverse
109 if not simpsons:
110 return False
111 return 1.0/simpsons
112
113 #Tested 4
114 @staticmethod
115 def funcGetShannonRichnessIndex(ldSampleTaxaAbundancies=None):
116 """
117 Calculates the Shannon richness index.
118 Note***: Assumes that the abundance measurements are already normalized by the total population N.
119 If not normalized, include N in the parameter tempTotalN and it will be.
120 This is in base exp(1) like the default R Vegan package. Cogent is by defaul in bits (base=2)
121 Both options are here for your use. See Metric.funcGetAlphaDiversity() to access cogent
122
123 :param ldSampleTaxaAbundancies: List of measurements to calculate metric on (a sample).
124 :type: List of doubles
125 :return Double: Richness metric
126 """
127
128 #Calculate metric
129 ldSampleTaxaAbundancies = ldSampleTaxaAbundancies[np.where(ldSampleTaxaAbundancies != 0)]
130 tempIntermediateNumber = sum(ldSampleTaxaAbundancies*(np.log(ldSampleTaxaAbundancies)))
131 if(tempIntermediateNumber == 0.0):
132 return 0.0
133 return -1 * tempIntermediateNumber
134
135 #Test 3
136 @staticmethod
137 def funcGetChao1DiversityIndex(ldSampleTaxaAbundancies=None, fCorrectForBias=False):
138 """
139 Calculates the Chao1 diversity index.
140 Note***: Not normalized by abundance.
141
142 :param ldSampleTaxaAbundancies: List of measurements to calculate metric on (a sample).
143 :type: List of doubles
144 :param fCorrectForBias: Indicator to use bias correction.
145 :type: Boolean False indicates uncorrected for bias (uncorrected = Chao 1984, corrected = Chao 1987, Eq. 2)
146 :return Double: Diversity metric
147 """
148 #If not counts return false
149 if [num for num in ldSampleTaxaAbundancies if((num<1) and (not num==0))]: return False
150
151 #Observed = total number of species observed in all samples pooled
152 totalObservedSpecies = len(ldSampleTaxaAbundancies)-len(ldSampleTaxaAbundancies[ldSampleTaxaAbundancies == 0])
153
154 #Singles = number of species that occur in exactly 1 sample
155 singlesObserved = len(ldSampleTaxaAbundancies[ldSampleTaxaAbundancies == 1.0])
156
157 #Doubles = number of species that occue in exactly 2 samples
158 doublesObserved = len(ldSampleTaxaAbundancies[ldSampleTaxaAbundancies == 2.0])
159
160 #If singles or doubles = 0, return observations so that a divided by zero error does not occur
161 if((singlesObserved == 0) or (doublesObserved == 0)):
162 return totalObservedSpecies
163
164 #Calculate metric
165 if fCorrectForBias:
166 return cogent.maths.stats.alpha_diversity.chao1_bias_corrected(observed = totalObservedSpecies, singles = singlesObserved, doubles = doublesObserved)
167 else:
168 return cogent.maths.stats.alpha_diversity.chao1_uncorrected(observed = totalObservedSpecies, singles = singlesObserved, doubles = doublesObserved)
169
170 #Test 3
171 @staticmethod
172 def funcGetObservedCount(ldSampleAbundances, dThreshold = 0.0):
173 """
174 Count how many bugs / features have a value of greater than 0 or the threshold given.
175 Expects a vector of abundances.
176 ****Do not normalize data if using the threshold.
177
178 :param ldSampleAbundances: List of measurements to calculate metric on (a sample).
179 :type: List of doubles
180 :param dThreshold: The lowest number the measurement can be to be counted as an observation.
181 :type: Double
182 :return Count: Number of features observed in a sample.
183 """
184
185 return sum([1 for observation in ldSampleAbundances if observation > dThreshold])
186
187 #Test Cases 6
188 @staticmethod
189 def funcGetAlphaDiversity(liCounts,strMetric):
190 """
191 Passes counts to cogent for an alpha diversity metric.
192 setAlphaDiversities are the names supported
193
194 :param liCount: List of counts to calculate metric on (a sample).
195 :type: List of ints
196 :return Diversity: Double diversity metric.
197 """
198
199 return getattr(cogent.maths.stats.alpha_diversity,strMetric)(liCounts)
200
201 #Happy path tested 1
202 @staticmethod
203 def funcGetDissimilarity(ldSampleTaxaAbundancies, funcDistanceFunction):
204 """
205 Calculates the distance between samples given a function.
206
207 If you have 5 rows (labeled r1,r2,r3,r4,r5) the vector are the distances in this order.
208 condensed form = [d(r1,r2), d(r1,r3), d(r1,r4), d(r1,r5), d(r2,r3), d(r2,r4), d(r2,r5), d(r3,r4), d(r3,r5), d(r4,r5)].
209 Note***: Assumes that the abundance measurements are already normalized by the total population N.
210
211 :param ldSampleTaxaAbundancies:
212 :type: List of doubles
213 :param funcDistanceFunction: Distance function used to calculate distances
214 :type: Function
215 :return Double: Dissimilarity metric
216 """
217
218 #Calculate metric
219 try:
220 return scipy.spatial.distance.pdist(ldSampleTaxaAbundancies, funcDistanceFunction)
221 except ValueError as error:
222 print "".join(["Metric.funcGetDissimilarity. Error=",str(error)])
223 return False
224
225 #Test case 1
226 @staticmethod
227 def funcGetDissimilarityByName(ldSampleTaxaAbundancies, strMetric):
228 """
229 Calculates beta-diversity metrics between lists of abundances
230 setBetaDiversities are the names supported
231
232 :param ldSampleTaxaAbundancies:
233 :type: List of doubles
234 :param strMetric: Name of the distance function used to calculate distances
235 :type: String
236 :return list double: Dissimilarity metrics between each sample
237 """
238
239 return scipy.spatial.distance.pdist(ldSampleTaxaAbundancies,strMetric)
240
241 #Test 3
242 @staticmethod
243 def funcGetBrayCurtisDissimilarity(ldSampleTaxaAbundancies):
244 """
245 Calculates the BrayCurtis Beta dissimilarity index.
246 d(u,v)=sum(abs(row1-row2))/sum(row1+row2).
247 This is scale invariant.
248 If you have 5 rows (labeled r1,r2,r3,r4,r5) the vector are the distances in this order.
249 condensed form = [d(r1,r2), d(r1,r3), d(r1,r4), d(r1,r5), d(r2,r3), d(r2,r4), d(r2,r5), d(r3,r4), d(r3,r5), d(r4,r5)].
250 Note***: Assumes that the abundance measurements are already normalized by the total population N.
251
252 :param ldSampleTaxaAbundancies:
253 :type: List of doubles
254 :return Double Matrix: Dissimilarity metric
255 """
256
257 #Calculate metric
258 try:
259 return scipy.spatial.distance.pdist(X=ldSampleTaxaAbundancies, metric='braycurtis')
260 except ValueError as error:
261 print "".join(["Metric.getBrayCurtisDissimilarity. Error=",str(error)])
262 return False
263
264 #Test 3
265 @staticmethod
266 def funcGetInverseBrayCurtisDissimilarity(ldSampleTaxaAbundancies):
267 """
268 Calculates 1 - the BrayCurtis Beta dissimilarity index.
269 d(u,v)=1-(sum(abs(row1-row2))/sum(row1+row2)).
270 This is scale invariant and ranges between 0 and 1.
271 If you have 5 rows (labeled r1,r2,r3,r4,r5) the vector are the distances in this order.
272 condensed form = [d(r1,r2), d(r1,r3), d(r1,r4), d(r1,r5), d(r2,r3), d(r2,r4), d(r2,r5), d(r3,r4), d(r3,r5), d(r4,r5)].
273 Note***: Assumes that the abundance measurements are already normalized by the total population N.
274
275 :param ldSampleTaxaAbundancies: An np.array of samples (rows) x measurements (columns) in which distance is measured between rows
276 :type: List List of doubles
277 :return Double Matrix: 1 - Bray-Curtis dissimilarity.
278 """
279
280 bcValue = Metric.funcGetBrayCurtisDissimilarity(ldSampleTaxaAbundancies = ldSampleTaxaAbundancies)
281 if not type(bcValue) is BooleanType:
282 return 1.0-bcValue
283 return False
284
285 #Test cases 8
286 @staticmethod
287 def funcGetUnifracDistance(istrmTree,istrmEnvr,lsSampleOrder=None,fWeighted=True):
288 """
289 Gets a unifrac distance from files/filestreams.
290
291 :param istrmTree: File path or stream which is a Newick format file
292 :type: String of file stream
293 :param istrmEnvr: File path or stream which is a Newick format file
294 :type: String of file stream
295 """
296 npaDist, lsSampleNames = fast_unifrac_file(open(istrmTree,"r") if isinstance(istrmTree, str) else istrmTree,
297 open(istrmEnvr,"r") if isinstance(istrmEnvr, str) else istrmEnvr, weighted=fWeighted).get("distance_matrix",False)
298
299 #Was trying to avoid preallocating a matrix but if you only need a subset of the samples then it
300 #is simpler to preallocate so this is what I am doing but making a condensed matrix and not a full matrix
301
302 #Dictionary to translate the current order of the samples to what is expected if given an input order
303 if lsSampleOrder:
304 #{NewOrder:OriginalOrder} way to convert from old to new sample location
305 dictTranslate = dict([[lsSampleOrder.index(sSampleName),lsSampleNames.index(sSampleName)] for sSampleName in lsSampleNames if sSampleName in lsSampleOrder])
306
307 #Check to make sure all samples requested were found
308 if not len(dictTranslate.keys()) == len(lsSampleOrder):
309 print "Metric.funcGetUnifracDistance. Error= The some or all sample names given (lsSampleOrder) were not contained in the matrix."
310 return False
311
312 #Length of data
313 iLengthOfData = len(lsSampleOrder)
314
315 #Preallocate matrix and shuffle
316 mtrxData = np.zeros(shape=(iLengthOfData,iLengthOfData))
317 for x in xrange(iLengthOfData):
318 for y in xrange(iLengthOfData):
319 mtrxData[x,y] = npaDist[dictTranslate[x],dictTranslate[y]]
320 npaDist = mtrxData
321
322 lsSampleNames = lsSampleOrder
323
324 #If no sample order is given, condense the matrix and return
325 return (scipy.spatial.distance.squareform(npaDist),lsSampleNames)
326
327
328 #Test 7
329 @staticmethod
330 def funcGetAlphaMetric(ldAbundancies, strMetric):
331 """
332 Get alpha abundance of the metric for the vector.
333 Note: Shannon is measured with base 2 ("shannon") or base exp(1) (Metric.c_strShannonRichness) depending which method is called.
334
335 :param ldAbundancies: List of values to compute metric (a sample).
336 :type: List List of doubles.
337 :param strMetric: The metric to measure.
338 :type: String Metric name (Use from constants above).
339 :return Double: Metric specified by strMetric derived from ldAbundancies.
340 """
341
342 if(strMetric == Metric.c_strShannonRichness):
343 return Metric.funcGetShannonRichnessIndex(ldSampleTaxaAbundancies=ldAbundancies)
344 elif(strMetric == Metric.c_strSimpsonDiversity):
345 return Metric.funcGetSimpsonsDiversityIndex(ldSampleTaxaAbundancies=ldAbundancies)
346 elif(strMetric == Metric.c_strInvSimpsonDiversity):
347 return Metric.funcGetInverseSimpsonsDiversityIndex(ldSampleTaxaAbundancies=ldAbundancies)
348 elif(strMetric == Metric.c_strObservedCount):
349 return Metric.funcGetObservedCount(ldSampleAbundances=ldAbundancies)
350 #Chao1 Needs NOT Normalized Abundance (Counts)
351 elif(strMetric == Metric.c_strChao1Diversity):
352 return Metric.funcGetChao1DiversityIndex(ldSampleTaxaAbundancies=ldAbundancies)
353 elif(strMetric in Metric.setAlphaDiversities):
354 return Metric.funcGetAlphaDiversity(liCounts=ldAbundancies, strMetric=strMetric)
355 else:
356 return False
357
358 #Test 5
359 @staticmethod
360 def funcBuildAlphaMetricsMatrix(npaSampleAbundance = None, lsSampleNames = None, lsDiversityMetricAlpha = None):
361 """
362 Build a matrix of alpha diversity metrics for each sample
363 Row = metric, column = sample
364
365 :param npaSampleAbundance: Observations (Taxa (row) x sample (column))
366 :type: Numpy Array
367 :param lsSampleNames: List of sample names of samples to measure (do not include the taxa id column name or other column names which should not be read).
368 :type: List of strings Strings being samples to measure from the npaSampleAbundance.
369 :param lsDiversityMetricAlpha: List of diversity metrics to use in measuring.
370 :type: List of strings Strings being metrics to derived from the indicated samples.
371 :return List of List of doubles: Each internal list is a list of (floats) indicating a specific metric measurement method measuring multiple samples
372 [[metric1-sample1, metric1-sample2, metric1-sample3],[metric1-sample1, metric1-sample2, metric1-sample3]]
373 """
374
375 if not ValidateData.funcIsValidList(lsDiversityMetricAlpha):
376 lsDiversityMetricAlpha = [lsDiversityMetricAlpha]
377
378 #Get amount of metrics
379 metricsCount = len(lsDiversityMetricAlpha)
380
381 #Create return
382 returnMetricsMatrixRet = [[] for index in lsDiversityMetricAlpha]
383
384 #For each sample get all metrics
385 #Place in list of lists
386 #[[metric1-sample1, metric1-sample2, metric1-sample3],[metric1-sample1, metric1-sample2, metric1-sample3]]
387 for sample in lsSampleNames:
388 sampleAbundance = npaSampleAbundance[sample]
389 for metricIndex in xrange(0,metricsCount):
390 returnMetricsMatrixRet[metricIndex].append(Metric.funcGetAlphaMetric(ldAbundancies = sampleAbundance, strMetric = lsDiversityMetricAlpha[metricIndex]))
391 return returnMetricsMatrixRet
392
393 #Testing 6 cases
394 @staticmethod
395 def funcGetBetaMetric(npadAbundancies=None, sMetric=None, istrmTree=None, istrmEnvr=None, lsSampleOrder=None, fAdditiveInverse = False):
396 """
397 Takes a matrix of values and returns a beta metric matrix. The metric returned is indicated by name (sMetric).
398
399 :param npadAbundancies: Numpy array of sample abundances to measure against.
400 :type: Numpy Array Numpy array where row=samples and columns = features.
401 :param sMetric: String name of beta metric. Possibilities are listed in microPITA.
402 :type: String String name of beta metric. Possibilities are listed in microPITA.
403 :return Double: Measurement indicated by metric for given abundance list
404 """
405
406 if sMetric == Metric.c_strBrayCurtisDissimilarity:
407 mtrxDistance = Metric.funcGetBrayCurtisDissimilarity(ldSampleTaxaAbundancies=npadAbundancies)
408 elif sMetric == Metric.c_strInvBrayCurtisDissimilarity:
409 mtrxDistance = Metric.funcGetInverseBrayCurtisDissimilarity(ldSampleTaxaAbundancies=npadAbundancies)
410 elif sMetric in Metric.setBetaDiversities:
411 mtrxDistance = Metric.funcGetDissimilarityByName(ldSampleTaxaAbundancies=npadAbundancies, strMetric=sMetric)
412 elif sMetric == Metric.c_strUnifracUnweighted:
413 mtrxDistance = Metric.funcGetUnifracDistance(istrmTree=istrmTree,istrmEnvr=istrmEnvr,lsSampleOrder=lsSampleOrder,fWeighted=False)
414 # mtrxDistance = xReturn[0] if not type(xReturn) is BooleanType else xReturn
415 elif sMetric == Metric.c_strUnifracWeighted:
416 mtrxDistance = Metric.funcGetUnifracDistance(istrmTree=istrmTree,istrmEnvr=istrmEnvr,lsSampleOrder=lsSampleOrder,fWeighted=True)
417 # mtrxDistance = xReturn[0] if not type(xReturn) is BooleanType else xReturn
418 else:
419 mtrxDistance = False
420 if fAdditiveInverse and not type(mtrxDistance) is BooleanType:
421 if sMetric in [Metric.c_strUnifracUnweighted,Metric.c_strUnifracWeighted]:
422 mtrxDistance = (1.0 - mtrxDistance[0],mtrxDistance[1])
423 else:
424 mtrxDistance = 1.0 - mtrxDistance
425 return mtrxDistance
426
427 #Test Cases 11
428 @staticmethod
429 def funcReadMatrixFile(istmMatrixFile, lsSampleOrder=None):
430 """
431 Reads in a file with a precalculated beta-diversty matrix.
432
433 :param istmMatrixFile: File with beta-diversity matrix
434 :type: FileStream of String file path
435 """
436
437 #Read in data
438 f = csv.reader(open(istmMatrixFile,"r") if isinstance(istmMatrixFile, str) else istmMatrixFile, delimiter=ConstantsBreadCrumbs.c_matrixFileDelim )
439
440 #Get header
441 try:
442 lsHeader = f.next()
443 except StopIteration:
444 return (False,False)
445 lsHeaderReducedToSamples = [sHeader for sHeader in lsHeader if sHeader in lsSampleOrder] if lsSampleOrder else lsHeader[1:]
446
447 #If no sample ordering is given, set the ordering to what is in the file
448 if not lsSampleOrder:
449 lsSampleOrder = lsHeaderReducedToSamples
450
451 #Preallocate matrix
452 mtrxData = np.zeros(shape=(len(lsSampleOrder),len(lsSampleOrder)))
453
454 #Make sure all samples requested are in the file
455 if(not len(lsSampleOrder) == len(lsHeaderReducedToSamples)): return False
456
457 for lsLine in f:
458 if lsLine[0] in lsSampleOrder:
459 iRowIndex = lsSampleOrder.index(lsLine[0])
460
461 for i in xrange(1,len(lsSampleOrder)):
462 iColumnIndexComing = lsHeader.index(lsSampleOrder[i])
463 iColumnIndexGoing = lsSampleOrder.index(lsSampleOrder[i])
464 mtrxData[iRowIndex,iColumnIndexGoing] = lsLine[iColumnIndexComing]
465 mtrxData[iColumnIndexGoing,iRowIndex] = lsLine[iColumnIndexComing]
466 tpleMData = mtrxData.shape
467 mtrxData = mtrxData if any(sum(ld)>0 for ld in mtrxData) or ((tpleMData[0]==1) and (tpleMData[1]==1)) else []
468 return (mtrxData,lsSampleOrder)
469
470 #Test cases 2
471 @staticmethod
472 def funcWriteMatrixFile(mtrxMatrix, ostmMatrixFile, lsSampleNames=None):
473 """
474 Writes a square matrix to file.
475
476 :param mtrxMatrix: Matrix to write to file
477 :type: Numpy array
478 :lsSampleNames: The names of the samples in the order of the matrix
479 :type: List of strings
480 :ostmBetaMatrixFile: File to write to
481 :type: String or file stream
482 """
483
484 if not sum(mtrxMatrix.shape)>0 or not ostmMatrixFile:
485 return False
486
487 #Check to make sure the sample names are the correct length
488 tpleiShape = mtrxMatrix.shape
489 if not lsSampleNames:
490 lsSampleNames = range(tpleiShape[0])
491 if not(len(lsSampleNames) == tpleiShape[0]):
492 print "".join(["Metric.funcWriteMatrixFile. Error= Length of sample names ("+str(len(lsSampleNames))+") and matrix ("+str(mtrxMatrix.shape)+") not equal."])
493 return False
494
495 #Write to file
496 ostmOut = csv.writer(open(ostmMatrixFile,"w") if isinstance(ostmMatrixFile,str) else ostmMatrixFile, delimiter=ConstantsBreadCrumbs.c_matrixFileDelim )
497
498 #Add the additional space at the beginning of the sample names to represent the id row/column
499 lsSampleNames = [""]+list(lsSampleNames)
500
501 #Write header and each row to file
502 ostmOut.writerow(lsSampleNames)
503 [ostmOut.writerow([lsSampleNames[iIndex+1]]+mtrxMatrix[iIndex,].tolist()) for iIndex in xrange(tpleiShape[0])]
504 return True