annotate pyPRADA_1.2/tools/samtools-0.1.16/misc/HmmGlocal.java @ 0:acc2ca1a3ba4

Uploaded

import java.io.*;
import java.lang.*;

public class HmmGlocal
{
	private double[] qual2prob;
	private double cd, ce; // gap open probility [1e-3], gap extension probability [0.1]
	private int cb; // band width [7]

	public HmmGlocal(final double d, final double e, final int b) {
		cd = d; ce = e; cb = b;
		qual2prob = new double[256];
		for (int i = 0; i < 256; ++i)
			qual2prob[i] = Math.pow(10, -i/10.);
	}
	private static int set_u(final int b, final int i, final int k) {
		int x = i - b;
		x = x > 0? x : 0;
		return (k + 1 - x) * 3;
	}
	public int hmm_glocal(final byte[] _ref, final byte[] _query, final byte[] _iqual, int[] state, byte[] q) {
		int i, k;
		/*** initialization ***/
		// change coordinates
		int l_ref = _ref.length;
		byte[] ref = new byte[l_ref+1];
		for (i = 0; i < l_ref; ++i) ref[i+1] = _ref[i]; // FIXME: this is silly...
		int l_query = _query.length;
		byte[] query = new byte[l_query+1];
		double[] qual = new double[l_query+1];
		for (i = 0; i < l_query; ++i) {
			query[i+1] = _query[i];
			qual[i+1] = qual2prob[_iqual[i]];
		}
		// set band width
		int bw2, bw = l_ref > l_query? l_ref : l_query;
		if (bw > cb) bw = cb;
		if (bw < Math.abs(l_ref - l_query)) bw = Math.abs(l_ref - l_query);
		bw2 = bw * 2 + 1;
		// allocate the forward and backward matrices f[][] and b[][] and the scaling array s[]
		double[][] f = new double[l_query+1][bw2*3 + 6];
		double[][] b = new double[l_query+1][bw2*3 + 6];
		double[] s = new double[l_query+2];
		// initialize transition probabilities
		double sM, sI, bM, bI;
		sM = sI = 1. / (2 * l_query + 2);
		bM = (1 - cd) / l_query; bI = cd / l_query; // (bM+bI)*l_query==1
		double[] m = new double[9];
		m[0*3+0] = (1 - cd - cd) * (1 - sM); m[0*3+1] = m[0*3+2] = cd * (1 - sM);
		m[1*3+0] = (1 - ce) * (1 - sI); m[1*3+1] = ce * (1 - sI); m[1*3+2] = 0.;
		m[2*3+0] = 1 - ce; m[2*3+1] = 0.; m[2*3+2] = ce;
		/*** forward ***/
		// f[0]
		f[0][set_u(bw, 0, 0)] = s[0] = 1.;
		{ // f[1]
			double[] fi = f[1];
			double sum;
			int beg = 1, end = l_ref < bw + 1? l_ref : bw + 1, _beg, _end;
			for (k = beg, sum = 0.; k <= end; ++k) {
				int u;
				double e = (ref[k] > 3 || query[1] > 3)? 1. : ref[k] == query[1]? 1. - qual[1] : qual[1] / 3.;
				u = set_u(bw, 1, k);
				fi[u+0] = e * bM; fi[u+1] = .25 * bI;
				sum += fi[u] + fi[u+1];
			}
			// rescale
			s[1] = sum;
			_beg = set_u(bw, 1, beg); _end = set_u(bw, 1, end); _end += 2;
			for (k = _beg; k <= _end; ++k) fi[k] /= sum;
		}
		// f[2..l_query]
		for (i = 2; i <= l_query; ++i) {
			double[] fi = f[i], fi1 = f[i-1];
			double sum, qli = qual[i];
			int beg = 1, end = l_ref, x, _beg, _end;
			byte qyi = query[i];
			x = i - bw; beg = beg > x? beg : x; // band start
			x = i + bw; end = end < x? end : x; // band end
			for (k = beg, sum = 0.; k <= end; ++k) {
				int u, v11, v01, v10;
				double e;
				e = (ref[k] > 3 || qyi > 3)? 1. : ref[k] == qyi? 1. - qli : qli / 3.;
				u = set_u(bw, i, k); v11 = set_u(bw, i-1, k-1); v10 = set_u(bw, i-1, k); v01 = set_u(bw, i, k-1);
				fi[u+0] = e * (m[0] * fi1[v11+0] + m[3] * fi1[v11+1] + m[6] * fi1[v11+2]);
				fi[u+1] = .25 * (m[1] * fi1[v10+0] + m[4] * fi1[v10+1]);
				fi[u+2] = m[2] * fi[v01+0] + m[8] * fi[v01+2];
				sum += fi[u] + fi[u+1] + fi[u+2];
				//System.out.println("("+i+","+k+";"+u+"): "+fi[u]+","+fi[u+1]+","+fi[u+2]);
			}
			// rescale
			s[i] = sum;
			_beg = set_u(bw, i, beg); _end = set_u(bw, i, end); _end += 2;
			for (k = _beg, sum = 1./sum; k <= _end; ++k) fi[k] *= sum;
		}
		{ // f[l_query+1]
			double sum;
			for (k = 1, sum = 0.; k <= l_ref; ++k) {
				int u = set_u(bw, l_query, k);
				if (u < 3 || u >= bw2*3+3) continue;
				sum += f[l_query][u+0] * sM + f[l_query][u+1] * sI;
			}
			s[l_query+1] = sum; // the last scaling factor
		}
		/*** backward ***/
		// b[l_query] (b[l_query+1][0]=1 and thus \tilde{b}[][]=1/s[l_query+1]; this is where s[l_query+1] comes from)
		for (k = 1; k <= l_ref; ++k) {
			int u = set_u(bw, l_query, k);
			double[] bi = b[l_query];
			if (u < 3 || u >= bw2*3+3) continue;
			bi[u+0] = sM / s[l_query] / s[l_query+1]; bi[u+1] = sI / s[l_query] / s[l_query+1];
		}
		// b[l_query-1..1]
		for (i = l_query - 1; i >= 1; --i) {
			int beg = 1, end = l_ref, x, _beg, _end;
			double[] bi = b[i], bi1 = b[i+1];
			double y = (i > 1)? 1. : 0., qli1 = qual[i+1];
			byte qyi1 = query[i+1];
			x = i - bw; beg = beg > x? beg : x;
			x = i + bw; end = end < x? end : x;
			for (k = end; k >= beg; --k) {
				int u, v11, v01, v10;
				double e;
				u = set_u(bw, i, k); v11 = set_u(bw, i+1, k+1); v10 = set_u(bw, i+1, k); v01 = set_u(bw, i, k+1);
				e = (k >= l_ref? 0 : (ref[k+1] > 3 || qyi1 > 3)? 1. : ref[k+1] == qyi1? 1. - qli1 : qli1 / 3.) * bi1[v11];
				bi[u+0] = e * m[0] + .25 * m[1] * bi1[v10+1] + m[2] * bi[v01+2]; // bi1[v11] has been foled into e.
				bi[u+1] = e * m[3] + .25 * m[4] * bi1[v10+1];
				bi[u+2] = (e * m[6] + m[8] * bi[v01+2]) * y;
			}
			// rescale
			_beg = set_u(bw, i, beg); _end = set_u(bw, i, end); _end += 2;
			for (k = _beg, y = 1./s[i]; k <= _end; ++k) bi[k] *= y;
		}
		double pb;
		{ // b[0]
			int beg = 1, end = l_ref < bw + 1? l_ref : bw + 1;
			double sum = 0.;
			for (k = end; k >= beg; --k) {
				int u = set_u(bw, 1, k);
				double e = (ref[k] > 3 || query[1] > 3)? 1. : ref[k] == query[1]? 1. - qual[1] : qual[1] / 3.;
				if (u < 3 || u >= bw2*3+3) continue;
				sum += e * b[1][u+0] * bM + .25 * b[1][u+1] * bI;
			}
			pb = b[0][set_u(bw, 0, 0)] = sum / s[0]; // if everything works as is expected, pb == 1.0
		}
		int is_diff = Math.abs(pb - 1.) > 1e-7? 1 : 0;
		/*** MAP ***/
		for (i = 1; i <= l_query; ++i) {
			double sum = 0., max = 0.;
			double[] fi = f[i], bi = b[i];
			int beg = 1, end = l_ref, x, max_k = -1;
			x = i - bw; beg = beg > x? beg : x;
			x = i + bw; end = end < x? end : x;
			for (k = beg; k <= end; ++k) {
				int u = set_u(bw, i, k);
				double z;
				sum += (z = fi[u+0] * bi[u+0]); if (z > max) { max = z; max_k = (k-1)<<2 | 0; }
				sum += (z = fi[u+1] * bi[u+1]); if (z > max) { max = z; max_k = (k-1)<<2 | 1; }
			}
			max /= sum; sum *= s[i]; // if everything works as is expected, sum == 1.0
			if (state != null) state[i-1] = max_k;
			if (q != null) {
				k = (int)(-4.343 * Math.log(1. - max) + .499);
				q[i-1] = (byte)(k > 100? 99 : k);
			}
			//System.out.println("("+pb+","+sum+")"+" ("+(i-1)+","+(max_k>>2)+","+(max_k&3)+","+max+")");
		}
		return 0;
	}

	public static void main(String[] args) {
		byte[] ref = {'\0', '\1', '\3', '\3', '\1'};
		byte[] query = {'\0', '\3', '\3', '\1'};
		byte[] qual = new byte[4];
		qual[0] = qual[1] = qual[2] = qual[3] = (byte)20;
		HmmGlocal hg = new HmmGlocal(1e-3, 0.1, 7);
		hg.hmm_glocal(ref, query, qual, null, null);
	}
}