diff bwa-0.6.2/bwtsw2_pair.c @ 2:a294fbfcb1db draft default tip

Uploaded BWA
author ashvark
date Fri, 18 Jul 2014 07:55:59 -0400
parents dd1186b11b3b
children
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/bwa-0.6.2/bwtsw2_pair.c	Fri Jul 18 07:55:59 2014 -0400
@@ -0,0 +1,291 @@
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "bwt.h"
+#include "bntseq.h"
+#include "bwtsw2.h"
+#include "kstring.h"
+#ifndef _NO_SSE2
+#include "ksw.h"
+#else
+#include "stdaln.h"
+#endif
+
+#define MIN_RATIO     0.8
+#define OUTLIER_BOUND 2.0
+#define MAX_STDDEV    4.0
+#define EXT_STDDEV    4.0
+
+typedef struct {
+	int low, high, failed;
+	double avg, std;
+} bsw2pestat_t;
+
+bsw2pestat_t bsw2_stat(int n, bwtsw2_t **buf, kstring_t *msg, int max_ins)
+{
+	extern void ks_introsort_uint64_t(size_t n, uint64_t *a);
+	int i, k, x, p25, p50, p75, tmp, max_len = 0;
+	uint64_t *isize;
+	bsw2pestat_t r;
+
+	memset(&r, 0, sizeof(bsw2pestat_t));
+	isize = calloc(n, 8);
+	for (i = k = 0; i < n; i += 2) {
+		bsw2hit_t *t[2];
+		int l;
+		if (buf[i] == 0 || buf[i]->n != 1 || buf[i+1]->n != 1) continue; // more than 1 hits
+		t[0] = &buf[i]->hits[0]; t[1] = &buf[i+1]->hits[0];
+		if (t[0]->G2 > 0.8 * t[0]->G) continue; // the best hit is not good enough
+		if (t[1]->G2 > 0.8 * t[1]->G) continue; // the best hit is not good enough
+		l = t[0]->k > t[1]->k? t[0]->k - t[1]->k + t[1]->len : t[1]->k - t[0]->k + t[0]->len;
+		if (l >= max_ins) continue; // skip pairs with excessively large insert
+		max_len = max_len > t[0]->end - t[0]->beg? max_len : t[0]->end - t[0]->beg;
+		max_len = max_len > t[1]->end - t[1]->beg? max_len : t[1]->end - t[1]->beg;
+		isize[k++] = l;
+	}
+	ks_introsort_uint64_t(k, isize);
+	p25 = isize[(int)(.25 * k + .499)];
+	p50 = isize[(int)(.50 * k + .499)];
+	p75 = isize[(int)(.75 * k + .499)];
+	ksprintf(msg, "[%s] infer the insert size distribution from %d high-quality pairs.\n", __func__, k);
+	if (k < 8) {
+		ksprintf(msg, "[%s] fail to infer the insert size distribution.\n", __func__);
+		free(isize);
+		r.failed = 1;
+		return r;
+	}
+	tmp    = (int)(p25 - OUTLIER_BOUND * (p75 - p25) + .499);
+	r.low  = tmp > max_len? tmp : max_len;
+	if (r.low < 1) r.low = 1;
+	r.high = (int)(p75 + OUTLIER_BOUND * (p75 - p25) + .499);
+	ksprintf(msg, "[%s] (25, 50, 75) percentile: (%d, %d, %d)\n", __func__, p25, p50, p75);
+	ksprintf(msg, "[%s] low and high boundaries for computing mean and std.dev: (%d, %d)\n", __func__, r.low, r.high);
+	for (i = x = 0, r.avg = 0; i < k; ++i)
+		if (isize[i] >= r.low && isize[i] <= r.high)
+			r.avg += isize[i], ++x;
+	r.avg /= x;
+	for (i = 0, r.std = 0; i < k; ++i)
+		if (isize[i] >= r.low && isize[i] <= r.high)
+			r.std += (isize[i] - r.avg) * (isize[i] - r.avg);
+	r.std = sqrt(r.std / x);
+	ksprintf(msg, "[%s] mean and std.dev: (%.2f, %.2f)\n", __func__, r.avg, r.std);
+	tmp  = (int)(p25 - 3. * (p75 - p25) + .499);
+	r.low  = tmp > max_len? tmp : max_len;
+	if (r.low < 1) r.low = 1;
+	r.high = (int)(p75 + 3. * (p75 - p25) + .499);
+	if (r.low > r.avg - MAX_STDDEV * 4.) r.low = (int)(r.avg - MAX_STDDEV * 4. + .499);
+	r.low = tmp > max_len? tmp : max_len;
+	if (r.high < r.avg - MAX_STDDEV * 4.) r.high = (int)(r.avg + MAX_STDDEV * 4. + .499);
+	ksprintf(msg, "[%s] low and high boundaries for proper pairs: (%d, %d)\n", __func__, r.low, r.high);
+	free(isize);
+	return r;
+}
+
+typedef struct {
+	int n_cigar, beg, end, len;
+	int64_t pos;
+	uint32_t *cigar;
+} pairaux_t;
+
+extern unsigned char nst_nt4_table[256];
+
+void bsw2_pair1(const bsw2opt_t *opt, int64_t l_pac, const uint8_t *pac, const bsw2pestat_t *st, const bsw2hit_t *h, int l_mseq, const char *mseq, bsw2hit_t *a, int8_t g_mat[25])
+{
+	extern void seq_reverse(int len, ubyte_t *seq, int is_comp);
+	int64_t k, beg, end;
+	uint8_t *seq, *ref;
+	int i;
+	// compute the region start and end
+	a->n_seeds = 1; a->flag |= BSW2_FLAG_MATESW; // before calling this routine, *a has been cleared with memset(0); the flag is set with 1<<6/7
+	if (h->is_rev == 0) {
+		beg = (int64_t)(h->k + st->avg - EXT_STDDEV * st->std - l_mseq + .499);
+		if (beg < h->k) beg = h->k;
+		end = (int64_t)(h->k + st->avg + EXT_STDDEV * st->std + .499);
+		a->is_rev = 1; a->flag |= 16;
+	} else {
+		beg = (int64_t)(h->k + h->end - h->beg - st->avg - EXT_STDDEV * st->std + .499);
+		end = (int64_t)(h->k + h->end - h->beg - st->avg + EXT_STDDEV * st->std + l_mseq + .499);
+		if (end > h->k + (h->end - h->beg)) end = h->k + (h->end - h->beg);
+		a->is_rev = 0;
+	}
+	if (beg < 1) beg = 1;
+	if (end > l_pac) end = l_pac;
+	if (end - beg < l_mseq) return;
+	// generate the sequence
+	seq = malloc(l_mseq + (end - beg));
+	ref = seq + l_mseq;
+	for (k = beg; k < end; ++k)
+		ref[k - beg] = pac[k>>2] >> ((~k&3)<<1) & 0x3;
+	if (h->is_rev == 0) {
+		for (i = 0; i < l_mseq; ++i) { // on the reverse strand
+			int c = nst_nt4_table[(int)mseq[i]];
+			seq[l_mseq - 1 - i] = c > 3? 4 : 3 - c;
+		}
+	} else {
+		for (i = 0; i < l_mseq; ++i) // on the forward strand
+			seq[i] = nst_nt4_table[(int)mseq[i]];
+	}
+#ifndef _NO_SSE2
+	{
+		ksw_query_t *q;
+		ksw_aux_t aux[2];
+		// forward Smith-Waterman
+		aux[0].T = opt->t; aux[0].gapo = opt->q; aux[0].gape = opt->r; aux[1] = aux[0];
+		q = ksw_qinit(l_mseq * g_mat[0] < 250? 1 : 2, l_mseq, seq, 5, g_mat);
+		ksw_sse2(q, end - beg, ref, &aux[0]);
+		free(q);
+		if (aux[0].score < opt->t) {
+			free(seq);
+			return;
+		}
+		++aux[0].qe; ++aux[0].te;
+		// reverse Smith-Waterman
+		seq_reverse(aux[0].qe, seq, 0);
+		seq_reverse(aux[0].te, ref, 0);
+		q = ksw_qinit(aux[0].qe * g_mat[0] < 250? 1 : 2, aux[0].qe, seq, 5, g_mat);
+		ksw_sse2(q, aux[0].te, ref, &aux[1]);
+		free(q);
+		++aux[1].qe; ++aux[1].te;
+		// write output
+		a->G = aux[0].score;
+		a->G2 = aux[0].score2 > aux[1].score2? aux[0].score2 : aux[1].score2;
+		if (a->G2 < opt->t) a->G2 = 0;
+		if (a->G2) a->flag |= BSW2_FLAG_TANDEM;
+		a->k = beg + (aux[0].te - aux[1].te);
+		a->len = aux[1].te;
+		a->beg = aux[0].qe - aux[1].qe;
+		a->end = aux[0].qe;
+	}
+#else
+	{
+		AlnParam ap;
+		path_t path[2];
+		int matrix[25];
+		for (i = 0; i < 25; ++i) matrix[i] = g_mat[i];
+		ap.gap_open = opt->q; ap.gap_ext = opt->r; ap.gap_end = opt->r;
+		ap.matrix = matrix; ap.row = 5; ap.band_width = 50;
+		a->G = aln_local_core(ref, end - beg, seq, l_mseq, &ap, path, 0, opt->t, &a->G2);
+		if (a->G < opt->t) a->G = 0;
+		if (a->G2 < opt->t) a->G2 = 0;
+		a->k = beg + path[0].i - 1;
+		a->len = path[1].i - path[0].i + 1;
+		a->beg = path[0].j - 1;
+		a->end = path[1].j;
+	}
+#endif
+	if (a->is_rev) i = a->beg, a->beg = l_mseq - a->end, a->end = l_mseq - i;
+	free(seq);
+}
+
+void bsw2_pair(const bsw2opt_t *opt, int64_t l_pac, const uint8_t *pac, int n, bsw2seq1_t *seq, bwtsw2_t **hits)
+{
+	extern int bsw2_resolve_duphits(const bntseq_t *bns, const bwt_t *bwt, bwtsw2_t *b, int IS);
+	bsw2pestat_t pes;
+	int i, j, k, n_rescued = 0, n_moved = 0, n_fixed = 0;
+	int8_t g_mat[25];
+	kstring_t msg;
+	memset(&msg, 0, sizeof(kstring_t));
+	pes = bsw2_stat(n, hits, &msg, opt->max_ins);
+	for (i = k = 0; i < 5; ++i) {
+		for (j = 0; j < 4; ++j)
+			g_mat[k++] = i == j? opt->a : -opt->b;
+		g_mat[k++] = 0;
+	}
+	for (i = 0; i < n; i += 2) {
+		bsw2hit_t a[2];
+		memset(&a, 0, sizeof(bsw2hit_t) * 2);
+		a[0].flag = 1<<6; a[1].flag = 1<<7;
+		for (j = 0; j < 2; ++j) { // set the read1/2 flag
+			if (hits[i+j] == 0) continue;
+			for (k = 0; k < hits[i+j]->n; ++k) {
+				bsw2hit_t *p = &hits[i+j]->hits[k];
+				p->flag |= 1<<(6+j);
+			}
+		}
+		if (pes.failed) continue;
+		if (hits[i] == 0 || hits[i+1] == 0) continue; // one end has excessive N
+		if (hits[i]->n != 1 && hits[i+1]->n != 1) continue; // no end has exactly one hit
+		if (hits[i]->n > 1 || hits[i+1]->n > 1) continue; // one read has more than one hit
+		if (!opt->skip_sw) {
+			if (hits[i+0]->n == 1) bsw2_pair1(opt, l_pac, pac, &pes, &hits[i+0]->hits[0], seq[i+1].l, seq[i+1].seq, &a[1], g_mat);
+			if (hits[i+1]->n == 1) bsw2_pair1(opt, l_pac, pac, &pes, &hits[i+1]->hits[0], seq[i+0].l, seq[i+0].seq, &a[0], g_mat);
+		} // else a[0].G == a[1].G == a[0].G2 == a[1].G2 == 0
+		// the following enumerate all possibilities. It is tedious but necessary...
+		if (hits[i]->n + hits[i+1]->n == 1) { // one end mapped; the other not;
+			bwtsw2_t *p[2];
+			int which;
+			if (hits[i]->n == 1) p[0] = hits[i], p[1] = hits[i+1], which = 1;
+			else p[0] = hits[i+1], p[1] = hits[i], which = 0;
+			if (a[which].G == 0) continue;
+			a[which].flag |= BSW2_FLAG_RESCUED;
+			if (p[1]->max == 0) {
+				p[1]->max = 1;
+				p[1]->hits = malloc(sizeof(bsw2hit_t));
+			}
+			p[1]->hits[0] = a[which];
+			p[1]->n = 1;
+			p[0]->hits[0].flag |= 2;
+			p[1]->hits[0].flag |= 2;
+			++n_rescued;
+		} else { // then both ends mapped
+			int is_fixed = 0;
+			//fprintf(stderr, "%d; %lld,%lld; %d,%d\n", a[0].is_rev, hits[i]->hits[0].k, a[0].k, hits[i]->hits[0].end, a[0].end);
+			for (j = 0; j < 2; ++j) { // fix wrong mappings and wrong suboptimal alignment score
+				bsw2hit_t *p = &hits[i+j]->hits[0];
+				if (p->G < a[j].G) { // the orginal mapping is suboptimal
+					a[j].G2 = a[j].G2 > p->G? a[j].G2 : p->G; // FIXME: reset BSW2_FLAG_TANDEM?
+					*p = a[j];
+					++n_fixed;
+					is_fixed = 1;
+				} else if (p->k != a[j].k && p->G2 < a[j].G) {
+					p->G2 = a[j].G;
+				} else if (p->k == a[j].k && p->G2 < a[j].G2) {
+					p->G2 = a[j].G2;
+				}
+			}
+			if (hits[i]->hits[0].k == a[0].k && hits[i+1]->hits[0].k == a[1].k) { // properly paired and no ends need to be moved
+				for (j = 0; j < 2; ++j)
+					hits[i+j]->hits[0].flag |= 2 | (a[j].flag & BSW2_FLAG_TANDEM);
+			} else if (hits[i]->hits[0].k == a[0].k || hits[i+1]->hits[0].k == a[1].k) { // a tandem match
+				for (j = 0; j < 2; ++j) {
+					hits[i+j]->hits[0].flag |= 2;
+					if (hits[i+j]->hits[0].k != a[j].k)
+						hits[i+j]->hits[0].flag |= BSW2_FLAG_TANDEM;
+				}
+			} else if (!is_fixed && (a[0].G || a[1].G)) { // it is possible to move one end
+				if (a[0].G && a[1].G) { // now we have two "proper pairs"
+					int G[2];
+					double diff;
+					G[0] = hits[i]->hits[0].G + a[1].G;
+					G[1] = hits[i+1]->hits[0].G + a[0].G;
+					diff = fabs(G[0] - G[1]) / (opt->a + opt->b) / ((hits[i]->hits[0].len + a[1].len + hits[i+1]->hits[0].len + a[0].len) / 2.);
+					if (diff > 0.05) a[G[0] > G[1]? 0 : 1].G = 0;
+				}
+				if (a[0].G == 0 || a[1].G == 0) { // one proper pair only
+					bsw2hit_t *p[2]; // p[0] points the unchanged hit; p[1] to the hit to be moved
+					int which, isize;
+					double dev, diff;
+					if (a[0].G) p[0] = &hits[i+1]->hits[0], p[1] = &hits[i]->hits[0], which = 0;
+					else p[0] = &hits[i]->hits[0], p[1] = &hits[i+1]->hits[0], which = 1;
+					isize = p[0]->is_rev? p[0]->k + p[0]->len - a[which].k : a[which].k + a[which].len - p[0]->k;
+					dev = fabs(isize - pes.avg) / pes.std;
+					diff = (double)(p[1]->G - a[which].G) / (opt->a + opt->b) / (p[1]->end - p[1]->beg) * 100.0;
+					if (diff < dev * 2.) { // then move (heuristic)
+						a[which].G2 = a[which].G;
+						p[1][0] = a[which];
+						p[1]->flag |= BSW2_FLAG_MOVED | 2;
+						p[0]->flag |= 2;
+						++n_moved;
+					}
+				}
+			} else if (is_fixed) {
+				hits[i+0]->hits[0].flag |= 2;
+				hits[i+1]->hits[0].flag |= 2;
+			}
+		}
+	}
+	ksprintf(&msg, "[%s] #fixed=%d, #rescued=%d, #moved=%d\n", __func__, n_fixed, n_rescued, n_moved);
+	fputs(msg.s, stderr);
+	free(msg.s);
+}