Пример #1
0
        /// <summary>
        /// Wavelets: unbalanced HAAR wavelets segmentation
        /// </summary>
        public Dictionary <string, SegmentationInput.Segment[]> Run(SegmentationInput segmentationInput, int windowSize)
        {
            double?coverageCV         = segmentationInput.GetCoverageVariability(windowSize);
            var    factorOfThreeCMADs = segmentationInput.FactorOfThreeCoverageVariabilities();;

            try
            {
                double evennessScore = segmentationInput.GetEvennessScore(windowSize);
                if (!segmentationInput.EvennessMetricFile.IsNullOrEmpty())
                {
                    CanvasIO.WriteEvennessMetricToTextFile(segmentationInput.EvennessMetricFile, evennessScore);
                }
            }
            catch (Exception)
            {
                Console.Error.WriteLine("Unable to calculate an evenness score, using coverage for segmentation");
            }

            Dictionary <string, List <int> > adjustedBreakpoints;

            var breakpoints = LaunchWavelets(segmentationInput.CoverageInfo.CoverageByChr, segmentationInput.CoverageInfo.StartByChr,
                                             segmentationInput.CoverageInfo.EndByChr, coverageCV, factorOfThreeCMADs);

            adjustedBreakpoints = AdjustBreakpoints(segmentationInput.CoverageInfo.CoverageByChr, breakpoints, vafContainingBinsByChr: null);

            var segments = new Dictionary <string, SegmentationInput.Segment[]>();

            foreach (string chr in segmentationInput.VafByChr.Keys)
            {
                segments[chr] = SegmentationInput.DeriveSegments(adjustedBreakpoints[chr], segmentationInput.CoverageInfo.CoverageByChr[chr].Length,
                                                                 segmentationInput.CoverageInfo.StartByChr[chr], segmentationInput.CoverageInfo.EndByChr[chr]);
            }
            return(segments);
        }
Пример #2
0
        public Dictionary <string, SegmentationInput.Segment[]> Run(List <SegmentationInput> segmentation, bool isPerSample)
        {
            var segmentByChr = new Dictionary <string, SegmentationInput.Segment[]>();

            var cts = new CancellationTokenSource();

            // Compute whole-genome median and inter-quartile-range-based pseudo-variance for each sample;
            // it would be better to exclude regions that are not diploid, and we should really be
            // using a different variance for each copy number, but using these values is better than
            // using the per-chromosome mean and variance, which have the following problems:
            // - chromosomes with a lot of outliers can get a very high variance
            // - chromosomes that have a whole-chromosome CNV or a CNV that affects a lot of the chromosome
            //   can have problematic estimates
            var medians         = new List <double>();
            var pseudoVariances = new List <double>();

            foreach (var singleSampleSegmentation in segmentation)
            {
                var cvgVals = new List <float>();
                foreach (var chr in singleSampleSegmentation.CoverageInfo.CoverageByChr.Keys)
                {
                    cvgVals.AddRange(singleSampleSegmentation.CoverageInfo.CoverageByChr[chr].Select(x => (float)x));
                }
                var quartiles = CanvasCommon.Utilities.Quartiles(cvgVals);
                medians.Add(quartiles.Item2);
                var iqr = quartiles.Item3 - quartiles.Item1;
                pseudoVariances.Add(iqr * iqr);
                //Console.WriteLine($"Global estimation of median and pseudovariance: {quartiles.Item2} {iqr * iqr}");
            }
            Parallel.ForEach(
                segmentation.First().CoverageInfo.CoverageByChr.Keys,
                new ParallelOptions
            {
                CancellationToken      = cts.Token,
                MaxDegreeOfParallelism = Environment.ProcessorCount,
                TaskScheduler          = TaskScheduler.Default
            },
                chr =>
            {
                var breakpoints         = new List <int>();
                int length              = segmentation.First().CoverageInfo.CoverageByChr[chr].Length;
                var startByChr          = segmentation.First().CoverageInfo.StartByChr[chr];
                var endByChr            = segmentation.First().CoverageInfo.EndByChr[chr];
                var multiSampleCoverage = new List <List <double> >(length);
                for (int i = 0; i < length; i++)
                {
                    multiSampleCoverage.Add(segmentation.Select(x => x.CoverageInfo.CoverageByChr[chr][i]).ToList());
                }

                if (length > _minSize)
                {
                    var haploidMeans = new List <double>(_nHiddenStates);
                    var negativeBinomialDistributions = isPerSample ?
                                                        InitializeNegativeBinomialEmission(multiSampleCoverage, _nHiddenStates, haploidMeans, medians, pseudoVariances)
                          : InitializeNegativeBinomialEmission(multiSampleCoverage, _nHiddenStates, haploidMeans, null, null);
                    //for (int j = 0; j < 1; j++)
                    //    for (int i = 0; i < 190; i++)
                    //    {
                    //        Console.WriteLine($"NegBin smp {j} count {i}: {negativeBinomialDistributions[0].Probability(j, i)} {negativeBinomialDistributions[1].Probability(j, i)} {negativeBinomialDistributions[2].Probability(j, i)} {negativeBinomialDistributions[3].Probability(j, i)} {negativeBinomialDistributions[4].Probability(j, i)}");
                    //    }
                    var hmm = new HiddenMarkovModel(multiSampleCoverage, negativeBinomialDistributions, haploidMeans, isPerSample);
                    Console.WriteLine($"{DateTime.Now} Launching HMM task for chromosome {chr}");
                    //if (_nSamples == 1)
                    //    hmm.FindMaximalLikelihood(multiSampleCoverage);
                    var bestPathViterbi = hmm.BestPathViterbi(multiSampleCoverage, startByChr, haploidMeans);
                    Console.WriteLine($"{DateTime.Now} Completed HMM task for chromosome {chr}");

                    breakpoints.Add(0);
                    for (int i = 1; i < length; i++)
                    {
                        if (bestPathViterbi[i] - bestPathViterbi[i - 1] != 0)
                        {
                            breakpoints.Add(i);
                        }
                    }

                    var segments = SegmentationInput.DeriveSegments(breakpoints, length, startByChr, endByChr);

                    lock (segmentByChr)
                    {
                        segmentByChr[chr] = segments;
                    }
                }
            });

            Console.WriteLine("{0} Completed HMM tasks", DateTime.Now);
            Console.WriteLine("{0} Segmentation results complete", DateTime.Now);
            return(segmentByChr);
        }