]> git.donarmstrong.com Git - samtools.git/blob - kaln.c
Implement the glocal HMM; discard the extention HMM
[samtools.git] / kaln.c
1 /* The MIT License
2
3    Copyright (c) 2003-2006, 2008, 2009, by Heng Li <lh3lh3@gmail.com>
4
5    Permission is hereby granted, free of charge, to any person obtaining
6    a copy of this software and associated documentation files (the
7    "Software"), to deal in the Software without restriction, including
8    without limitation the rights to use, copy, modify, merge, publish,
9    distribute, sublicense, and/or sell copies of the Software, and to
10    permit persons to whom the Software is furnished to do so, subject to
11    the following conditions:
12
13    The above copyright notice and this permission notice shall be
14    included in all copies or substantial portions of the Software.
15
16    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
20    BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
21    ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22    CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23    SOFTWARE.
24 */
25
26 #include <stdlib.h>
27 #include <stdio.h>
28 #include <string.h>
29 #include <stdint.h>
30 #include <math.h>
31 #include "kaln.h"
32
33 #define FROM_M 0
34 #define FROM_I 1
35 #define FROM_D 2
36
37 typedef struct {
38         int i, j;
39         unsigned char ctype;
40 } path_t;
41
42 int aln_sm_blosum62[] = {
43 /*       A  R  N  D  C  Q  E  G  H  I  L  K  M  F  P  S  T  W  Y  V  *  X */
44          4,-1,-2,-2, 0,-1,-1, 0,-2,-1,-1,-1,-1,-2,-1, 1, 0,-3,-2, 0,-4, 0,
45         -1, 5, 0,-2,-3, 1, 0,-2, 0,-3,-2, 2,-1,-3,-2,-1,-1,-3,-2,-3,-4,-1,
46         -2, 0, 6, 1,-3, 0, 0, 0, 1,-3,-3, 0,-2,-3,-2, 1, 0,-4,-2,-3,-4,-1,
47         -2,-2, 1, 6,-3, 0, 2,-1,-1,-3,-4,-1,-3,-3,-1, 0,-1,-4,-3,-3,-4,-1,
48          0,-3,-3,-3, 9,-3,-4,-3,-3,-1,-1,-3,-1,-2,-3,-1,-1,-2,-2,-1,-4,-2,
49         -1, 1, 0, 0,-3, 5, 2,-2, 0,-3,-2, 1, 0,-3,-1, 0,-1,-2,-1,-2,-4,-1,
50         -1, 0, 0, 2,-4, 2, 5,-2, 0,-3,-3, 1,-2,-3,-1, 0,-1,-3,-2,-2,-4,-1,
51          0,-2, 0,-1,-3,-2,-2, 6,-2,-4,-4,-2,-3,-3,-2, 0,-2,-2,-3,-3,-4,-1,
52         -2, 0, 1,-1,-3, 0, 0,-2, 8,-3,-3,-1,-2,-1,-2,-1,-2,-2, 2,-3,-4,-1,
53         -1,-3,-3,-3,-1,-3,-3,-4,-3, 4, 2,-3, 1, 0,-3,-2,-1,-3,-1, 3,-4,-1,
54         -1,-2,-3,-4,-1,-2,-3,-4,-3, 2, 4,-2, 2, 0,-3,-2,-1,-2,-1, 1,-4,-1,
55         -1, 2, 0,-1,-3, 1, 1,-2,-1,-3,-2, 5,-1,-3,-1, 0,-1,-3,-2,-2,-4,-1,
56         -1,-1,-2,-3,-1, 0,-2,-3,-2, 1, 2,-1, 5, 0,-2,-1,-1,-1,-1, 1,-4,-1,
57         -2,-3,-3,-3,-2,-3,-3,-3,-1, 0, 0,-3, 0, 6,-4,-2,-2, 1, 3,-1,-4,-1,
58         -1,-2,-2,-1,-3,-1,-1,-2,-2,-3,-3,-1,-2,-4, 7,-1,-1,-4,-3,-2,-4,-2,
59          1,-1, 1, 0,-1, 0, 0, 0,-1,-2,-2, 0,-1,-2,-1, 4, 1,-3,-2,-2,-4, 0,
60          0,-1, 0,-1,-1,-1,-1,-2,-2,-1,-1,-1,-1,-2,-1, 1, 5,-2,-2, 0,-4, 0,
61         -3,-3,-4,-4,-2,-2,-3,-2,-2,-3,-2,-3,-1, 1,-4,-3,-2,11, 2,-3,-4,-2,
62         -2,-2,-2,-3,-2,-1,-2,-3, 2,-1,-1,-2,-1, 3,-3,-2,-2, 2, 7,-1,-4,-1,
63          0,-3,-3,-3,-1,-2,-2,-3,-3, 3, 1,-2, 1,-1,-2,-2, 0,-3,-1, 4,-4,-1,
64         -4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4, 1,-4,
65          0,-1,-1,-1,-2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-2, 0, 0,-2,-1,-1,-4,-1
66 };
67
68 int aln_sm_blast[] = {
69         1, -3, -3, -3, -2,
70         -3, 1, -3, -3, -2,
71         -3, -3, 1, -3, -2,
72         -3, -3, -3, 1, -2,
73         -2, -2, -2, -2, -2
74 };
75
76 ka_param_t ka_param_blast = {  5,  2,   5, 2, aln_sm_blast, 5, 50 };
77 ka_param_t ka_param_aa2aa = { 10,  2,  10, 2, aln_sm_blosum62, 22, 50 };
78
79 static uint32_t *ka_path2cigar32(const path_t *path, int path_len, int *n_cigar)
80 {
81         int i, n;
82         uint32_t *cigar;
83         unsigned char last_type;
84
85         if (path_len == 0 || path == 0) {
86                 *n_cigar = 0;
87                 return 0;
88         }
89
90         last_type = path->ctype;
91         for (i = n = 1; i < path_len; ++i) {
92                 if (last_type != path[i].ctype) ++n;
93                 last_type = path[i].ctype;
94         }
95         *n_cigar = n;
96         cigar = (uint32_t*)calloc(*n_cigar, 4);
97
98         cigar[0] = 1u << 4 | path[path_len-1].ctype;
99         last_type = path[path_len-1].ctype;
100         for (i = path_len - 2, n = 0; i >= 0; --i) {
101                 if (path[i].ctype == last_type) cigar[n] += 1u << 4;
102                 else {
103                         cigar[++n] = 1u << 4 | path[i].ctype;
104                         last_type = path[i].ctype;
105                 }
106         }
107
108         return cigar;
109 }
110
111 /***************************/
112 /* START OF common_align.c */
113 /***************************/
114
115 #define SET_INF(s) (s).M = (s).I = (s).D = MINOR_INF;
116
117 #define set_M(MM, cur, p, sc)                                                   \
118 {                                                                                                               \
119         if ((p)->M >= (p)->I) {                                                         \
120                 if ((p)->M >= (p)->D) {                                                 \
121                         (MM) = (p)->M + (sc); (cur)->Mt = FROM_M;       \
122                 } else {                                                                                \
123                         (MM) = (p)->D + (sc); (cur)->Mt = FROM_D;       \
124                 }                                                                                               \
125         } else {                                                                                        \
126                 if ((p)->I > (p)->D) {                                                  \
127                         (MM) = (p)->I + (sc); (cur)->Mt = FROM_I;       \
128                 } else {                                                                                \
129                         (MM) = (p)->D + (sc); (cur)->Mt = FROM_D;       \
130                 }                                                                                               \
131         }                                                                                                       \
132 }
133 #define set_I(II, cur, p)                                                               \
134 {                                                                                                               \
135         if ((p)->M - gap_open > (p)->I) {                                       \
136                 (cur)->It = FROM_M;                                                             \
137                 (II) = (p)->M - gap_open - gap_ext;                             \
138         } else {                                                                                        \
139                 (cur)->It = FROM_I;                                                             \
140                 (II) = (p)->I - gap_ext;                                                \
141         }                                                                                                       \
142 }
143 #define set_end_I(II, cur, p)                                                   \
144 {                                                                                                               \
145         if (gap_end_ext >= 0) {                                                         \
146                 if ((p)->M - gap_end_open > (p)->I) {                   \
147                         (cur)->It = FROM_M;                                                     \
148                         (II) = (p)->M - gap_end_open - gap_end_ext;     \
149                 } else {                                                                                \
150                         (cur)->It = FROM_I;                                                     \
151                         (II) = (p)->I - gap_end_ext;                            \
152                 }                                                                                               \
153         } else set_I(II, cur, p);                                                       \
154 }
155 #define set_D(DD, cur, p)                                                               \
156 {                                                                                                               \
157         if ((p)->M - gap_open > (p)->D) {                                       \
158                 (cur)->Dt = FROM_M;                                                             \
159                 (DD) = (p)->M - gap_open - gap_ext;                             \
160         } else {                                                                                        \
161                 (cur)->Dt = FROM_D;                                                             \
162                 (DD) = (p)->D - gap_ext;                                                \
163         }                                                                                                       \
164 }
165 #define set_end_D(DD, cur, p)                                                   \
166 {                                                                                                               \
167         if (gap_end_ext >= 0) {                                                         \
168                 if ((p)->M - gap_end_open > (p)->D) {                   \
169                         (cur)->Dt = FROM_M;                                                     \
170                         (DD) = (p)->M - gap_end_open - gap_end_ext;     \
171                 } else {                                                                                \
172                         (cur)->Dt = FROM_D;                                                     \
173                         (DD) = (p)->D - gap_end_ext;                            \
174                 }                                                                                               \
175         } else set_D(DD, cur, p);                                                       \
176 }
177
178 typedef struct {
179         uint8_t Mt:3, It:2, Dt:2;
180 } dpcell_t;
181
182 typedef struct {
183         int M, I, D;
184 } dpscore_t;
185
186 /***************************
187  * banded global alignment *
188  ***************************/
189 uint32_t *ka_global_core(uint8_t *seq1, int len1, uint8_t *seq2, int len2, const ka_param_t *ap, int *_score, int *n_cigar)
190 {
191         int i, j;
192         dpcell_t **dpcell, *q;
193         dpscore_t *curr, *last, *s;
194         int b1, b2, tmp_end;
195         int *mat, end, max = 0;
196         uint8_t type, ctype;
197         uint32_t *cigar = 0;
198
199         int gap_open, gap_ext, gap_end_open, gap_end_ext, b;
200         int *score_matrix, N_MATRIX_ROW;
201
202         /* initialize some align-related parameters. just for compatibility */
203         gap_open = ap->gap_open;
204         gap_ext = ap->gap_ext;
205         gap_end_open = ap->gap_end_open;
206         gap_end_ext = ap->gap_end_ext;
207         b = ap->band_width;
208         score_matrix = ap->matrix;
209         N_MATRIX_ROW = ap->row;
210
211         *n_cigar = 0;
212         if (len1 == 0 || len2 == 0) return 0;
213
214         /* calculate b1 and b2 */
215         if (len1 > len2) {
216                 b1 = len1 - len2 + b;
217                 b2 = b;
218         } else {
219                 b1 = b;
220                 b2 = len2 - len1 + b;
221         }
222         if (b1 > len1) b1 = len1;
223         if (b2 > len2) b2 = len2;
224         --seq1; --seq2;
225
226         /* allocate memory */
227         end = (b1 + b2 <= len1)? (b1 + b2 + 1) : (len1 + 1);
228         dpcell = (dpcell_t**)malloc(sizeof(dpcell_t*) * (len2 + 1));
229         for (j = 0; j <= len2; ++j)
230                 dpcell[j] = (dpcell_t*)malloc(sizeof(dpcell_t) * end);
231         for (j = b2 + 1; j <= len2; ++j)
232                 dpcell[j] -= j - b2;
233         curr = (dpscore_t*)malloc(sizeof(dpscore_t) * (len1 + 1));
234         last = (dpscore_t*)malloc(sizeof(dpscore_t) * (len1 + 1));
235         
236         /* set first row */
237         SET_INF(*curr); curr->M = 0;
238         for (i = 1, s = curr + 1; i < b1; ++i, ++s) {
239                 SET_INF(*s);
240                 set_end_D(s->D, dpcell[0] + i, s - 1);
241         }
242         s = curr; curr = last; last = s;
243
244         /* core dynamic programming, part 1 */
245         tmp_end = (b2 < len2)? b2 : len2 - 1;
246         for (j = 1; j <= tmp_end; ++j) {
247                 q = dpcell[j]; s = curr; SET_INF(*s);
248                 set_end_I(s->I, q, last);
249                 end = (j + b1 <= len1 + 1)? (j + b1 - 1) : len1;
250                 mat = score_matrix + seq2[j] * N_MATRIX_ROW;
251                 ++s; ++q;
252                 for (i = 1; i != end; ++i, ++s, ++q) {
253                         set_M(s->M, q, last + i - 1, mat[seq1[i]]); /* this will change s->M ! */
254                         set_I(s->I, q, last + i);
255                         set_D(s->D, q, s - 1);
256                 }
257                 set_M(s->M, q, last + i - 1, mat[seq1[i]]);
258                 set_D(s->D, q, s - 1);
259                 if (j + b1 - 1 > len1) { /* bug fixed, 040227 */
260                         set_end_I(s->I, q, last + i);
261                 } else s->I = MINOR_INF;
262                 s = curr; curr = last; last = s;
263         }
264         /* last row for part 1, use set_end_D() instead of set_D() */
265         if (j == len2 && b2 != len2 - 1) {
266                 q = dpcell[j]; s = curr; SET_INF(*s);
267                 set_end_I(s->I, q, last);
268                 end = (j + b1 <= len1 + 1)? (j + b1 - 1) : len1;
269                 mat = score_matrix + seq2[j] * N_MATRIX_ROW;
270                 ++s; ++q;
271                 for (i = 1; i != end; ++i, ++s, ++q) {
272                         set_M(s->M, q, last + i - 1, mat[seq1[i]]); /* this will change s->M ! */
273                         set_I(s->I, q, last + i);
274                         set_end_D(s->D, q, s - 1);
275                 }
276                 set_M(s->M, q, last + i - 1, mat[seq1[i]]);
277                 set_end_D(s->D, q, s - 1);
278                 if (j + b1 - 1 > len1) { /* bug fixed, 040227 */
279                         set_end_I(s->I, q, last + i);
280                 } else s->I = MINOR_INF;
281                 s = curr; curr = last; last = s;
282                 ++j;
283         }
284
285         /* core dynamic programming, part 2 */
286         for (; j <= len2 - b2 + 1; ++j) {
287                 SET_INF(curr[j - b2]);
288                 mat = score_matrix + seq2[j] * N_MATRIX_ROW;
289                 end = j + b1 - 1;
290                 for (i = j - b2 + 1, q = dpcell[j] + i, s = curr + i; i != end; ++i, ++s, ++q) {
291                         set_M(s->M, q, last + i - 1, mat[seq1[i]]);
292                         set_I(s->I, q, last + i);
293                         set_D(s->D, q, s - 1);
294                 }
295                 set_M(s->M, q, last + i - 1, mat[seq1[i]]);
296                 set_D(s->D, q, s - 1);
297                 s->I = MINOR_INF;
298                 s = curr; curr = last; last = s;
299         }
300
301         /* core dynamic programming, part 3 */
302         for (; j < len2; ++j) {
303                 SET_INF(curr[j - b2]);
304                 mat = score_matrix + seq2[j] * N_MATRIX_ROW;
305                 for (i = j - b2 + 1, q = dpcell[j] + i, s = curr + i; i < len1; ++i, ++s, ++q) {
306                         set_M(s->M, q, last + i - 1, mat[seq1[i]]);
307                         set_I(s->I, q, last + i);
308                         set_D(s->D, q, s - 1);
309                 }
310                 set_M(s->M, q, last + len1 - 1, mat[seq1[i]]);
311                 set_end_I(s->I, q, last + i);
312                 set_D(s->D, q, s - 1);
313                 s = curr; curr = last; last = s;
314         }
315         /* last row */
316         if (j == len2) {
317                 SET_INF(curr[j - b2]);
318                 mat = score_matrix + seq2[j] * N_MATRIX_ROW;
319                 for (i = j - b2 + 1, q = dpcell[j] + i, s = curr + i; i < len1; ++i, ++s, ++q) {
320                         set_M(s->M, q, last + i - 1, mat[seq1[i]]);
321                         set_I(s->I, q, last + i);
322                         set_end_D(s->D, q, s - 1);
323                 }
324                 set_M(s->M, q, last + len1 - 1, mat[seq1[i]]);
325                 set_end_I(s->I, q, last + i);
326                 set_end_D(s->D, q, s - 1);
327                 s = curr; curr = last; last = s;
328         }
329
330         *_score = last[len1].M;
331         if (n_cigar) { /* backtrace */
332                 path_t *p, *path = (path_t*)malloc(sizeof(path_t) * (len1 + len2 + 2));
333                 i = len1; j = len2;
334                 q = dpcell[j] + i;
335                 s = last + len1;
336                 max = s->M; type = q->Mt; ctype = FROM_M;
337                 if (s->I > max) { max = s->I; type = q->It; ctype = FROM_I; }
338                 if (s->D > max) { max = s->D; type = q->Dt; ctype = FROM_D; }
339
340                 p = path;
341                 p->ctype = ctype; p->i = i; p->j = j; /* bug fixed 040408 */
342                 ++p;
343                 do {
344                         switch (ctype) {
345                         case FROM_M: --i; --j; break;
346                         case FROM_I: --j; break;
347                         case FROM_D: --i; break;
348                         }
349                         q = dpcell[j] + i;
350                         ctype = type;
351                         switch (type) {
352                         case FROM_M: type = q->Mt; break;
353                         case FROM_I: type = q->It; break;
354                         case FROM_D: type = q->Dt; break;
355                         }
356                         p->ctype = ctype; p->i = i; p->j = j;
357                         ++p;
358                 } while (i || j);
359                 cigar = ka_path2cigar32(path, p - path - 1, n_cigar);
360                 free(path);
361         }
362
363         /* free memory */
364         for (j = b2 + 1; j <= len2; ++j)
365                 dpcell[j] += j - b2;
366         for (j = 0; j <= len2; ++j)
367                 free(dpcell[j]);
368         free(dpcell);
369         free(curr); free(last);
370
371         return cigar;
372 }
373
374 /***************************
375  * Probabilistic extension *
376  ***************************/
377
378 #define set_u(u, b, i, k) { int x=(i)-(b); x=x>0?x:0; (u)=((k)-x+1)*3; }
379
380 ka_probpar_t ka_probpar_def = { 0.001, 0.1, 10 };
381
382 /*
383   The topology of the profile HMM:
384
385            /\             /\        /\             /\
386            I[1]           I[k-1]    I[k]           I[L]
387             ^   \      \    ^    \   ^   \      \   ^
388             |    \      \   |     \  |    \      \  |
389     M[0]   M[1] -> ... -> M[k-1] -> M[k] -> ... -> M[L]   M[L+1]
390                 \      \/        \/      \/      /
391                  \     /\        /\      /\     /
392                        -> D[k-1] -> D[k] ->
393                           \/        \/
394
395    M[0] points to every {M,I}[k] and every {M,I}[k] points M[L+1].
396  */
397 int ka_prob_glocal(const uint8_t *_ref, int l_ref, const uint8_t *_query, int l_query, const float *_qual,
398                                    const ka_probpar_t *c, int *state, uint8_t *q)
399 {
400         double **f, **b, *s, m[9], sI, sM, bI, bM, pb;
401         const float *qual;
402         const uint8_t *ref, *query;
403         int bw, bw2, i, k, is_diff = 0;
404
405         /*** initialization ***/
406         ref = _ref - 1; query = _query - 1; qual = _qual - 1; // change to 1-based coordinate
407         bw = l_ref > l_query? l_ref : l_query;
408         if (bw > c->bw) bw = c->bw;
409         if (bw < abs(l_ref - l_query)) bw = abs(l_ref - l_query);
410         bw2 = bw * 2 + 1;
411         // allocate the forward and backward matrices f[][] and b[][] and the scaling array s[]
412         f = calloc(l_query+1, sizeof(void*));
413         b = calloc(l_query+1, sizeof(void*));
414         for (i = 0; i <= l_query; ++i) {
415                 f[i] = calloc(bw2 * 3 + 6, sizeof(double)); // FIXME: this is over-allocated for very short seqs
416                 b[i] = calloc(bw2 * 3 + 6, sizeof(double));
417         }
418         s = calloc(l_query+2, sizeof(double)); // s[] is the scaling factor to avoid underflow
419         // initialize transition probability
420         sM = sI = 1. / (2 * l_query + 2); // the value here seems not to affect results; FIXME: need proof
421         m[0*3+0] = (1 - c->d - c->d) * (1 - sM); m[0*3+1] = m[0*3+2] = c->d * (1 - sM);
422         m[1*3+0] = (1 - c->e) * (1 - sI); m[1*3+1] = c->e * (1 - sI); m[1*3+2] = 0.;
423         m[2*3+0] = 1 - c->e; m[2*3+1] = 0.; m[2*3+2] = c->e;
424         bM = (1 - c->d) / l_query; bI = c->d / l_query; // (bM+bI)*l_query==1
425         /*** forward ***/
426         // f[0]
427         set_u(k, bw, 0, 0);
428         f[0][k] = s[0] = 1.;
429         { // f[1]
430                 double *fi = f[1], sum;
431                 int beg = 1, end = l_ref < bw + 1? l_ref : bw + 1, _beg, _end;
432                 for (k = beg, sum = 0.; k <= end; ++k) {
433                         int u;
434                         double e = (ref[k] > 3 || query[1] > 3)? 1. : ref[k] == query[1]? 1. - qual[1] : qual[1] / 3.;
435                         set_u(u, bw, 1, k);
436                         fi[u+0] = e * bM; fi[u+1] = .25 * bI;
437                         sum += fi[u] + fi[u+1];
438                 }
439                 // rescale
440                 s[1] = sum;
441                 set_u(_beg, bw, 1, beg); set_u(_end, bw, 1, end); _end += 2;
442                 for (k = _beg; k <= _end; ++k) fi[k] /= sum;
443         }
444         // f[2..l_query]
445         for (i = 2; i <= l_query; ++i) {
446                 double *fi = f[i], *fi1 = f[i-1], sum;
447                 int beg = 1, end = l_ref, x, _beg, _end;
448                 x = i - bw; beg = beg > x? beg : x; // band start
449                 x = i + bw; end = end < x? end : x; // band end
450                 for (k = beg, sum = 0.; k <= end; ++k) {
451                         int u, v11, v01, v10;
452                         double e;
453                         // FIXME: the following line can be optimized without branching
454                         e = (ref[k] > 3 || query[i] > 3)? 1. : ref[k] == query[i]? 1. - qual[i] : qual[i] / 3.;
455                         set_u(u, bw, i, k); set_u(v11, bw, i-1, k-1); set_u(v10, bw, i-1, k); set_u(v01, bw, i, k-1);
456                         fi[u+0] = e * (m[0] * fi1[v11+0] + m[3] * fi1[v11+1] + m[6] * fi1[v11+2]);
457                         fi[u+1] = .25 * (m[1] * fi1[v10+0] + m[4] * fi1[v10+1]);
458                         fi[u+2] = m[2] * fi[v01+0] + m[8] * fi[v01+2];
459                         sum += fi[u] + fi[u+1] + fi[u+2];
460 //                      fprintf(stderr, "F (%d,%d;%d): %lg,%lg,%lg\n", i, k, u, fi[u], fi[u+1], fi[u+2]); // DEBUG
461                 }
462                 // rescale
463                 s[i] = sum;
464                 set_u(_beg, bw, i, beg); set_u(_end, bw, i, end); _end += 2;
465                 for (k = _beg; k <= _end; ++k) fi[k] /= sum;
466         }
467         { // f[l_query+1]
468                 double sum;
469                 for (k = 1, sum = 0.; k <= l_ref; ++k) {
470                         int u;
471                         set_u(u, bw, l_query, k);
472                         if (u < 3 || u >= bw2*3+3) continue;
473                     sum += f[l_query][u+0] * sM + f[l_query][u+1] * sI;
474                 }
475                 s[l_query+1] = sum; // the last scaling factor
476         }
477         /*** backward ***/
478         // 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)
479         for (k = 1; k <= l_ref; ++k) {
480                 int u;
481                 double *bi = b[l_query];
482                 set_u(u, bw, l_query, k);
483                 if (u < 3 || u >= bw2*3+3) continue;
484                 bi[u+0] = sM / s[l_query] / s[l_query+1]; bi[u+1] = sI / s[l_query] / s[l_query+1];
485         }
486         // b[l_query-1..1]
487         for (i = l_query - 1; i >= 1; --i) {
488                 int beg = 1, end = l_ref, x, _beg, _end;
489                 double *bi = b[i], *bi1 = b[i+1];
490                 x = i - bw; beg = beg > x? beg : x;
491                 x = i + bw; end = end < x? end : x;
492                 for (k = end; k >= beg; --k) {
493                         int u, v11, v01, v10;
494                         double e;
495                         // FIXME: the following can be optimized without branching
496                         e = k >= l_ref? 0 : (ref[k+1] > 3 || query[i+1] > 3)? 1. : ref[k+1] == query[i+1]? 1. - qual[i+1] : qual[i+1] / 3.;
497                         set_u(u, bw, i, k); set_u(v11, bw, i+1, k+1); set_u(v10, bw, i+1, k); set_u(v01, bw, i, k+1);
498                         bi[u+0] = e * m[0] * bi1[v11+0] + .25 * m[1] * bi1[v10+1] + m[2] * bi[v01+2];
499                         bi[u+1] = e * m[3] * bi1[v11+0] + .25 * m[4] * bi1[v10+1];
500                         // FIXME: I do not know why I need this (i>1) factor, but only with it the result is correct
501                         bi[u+2] = (e * m[6] * bi1[v11+0] + m[8] * bi[v01+2]) * (i > 1);
502 //                      fprintf(stderr, "B (%d,%d;%d): %lg,%lg,%lg\n", i, k, u, bi[u], bi[u+1], bi[u+2]); // DEBUG
503                 }
504                 // rescale
505                 set_u(_beg, bw, i, beg); set_u(_end, bw, i, end); _end += 2;
506                 for (k = _beg; k <= _end; ++k) bi[k] /= s[i];
507         }
508         { // b[0]
509                 int beg = 1, end = l_ref < bw + 1? l_ref : bw + 1;
510                 double sum = 0.;
511                 for (k = end; k >= beg; --k) {
512                         int u;
513                         double e = (ref[k] > 3 || query[1] > 3)? 1. : ref[k] == query[1]? 1. - qual[1] : qual[1] / 3.;
514                         set_u(u, bw, 1, k);
515                         if (u < 3 || u >= bw2*3+3) continue;
516                     sum += e * b[1][u+0] * bM + .25 * b[1][u+1] * bI;
517                 }
518                 set_u(k, bw, 0, 0);
519                 pb = b[0][k] = sum / s[0];
520         }
521         is_diff = fabs(pb - 1.) > 1e-7? 1 : 0;
522         /*** MAP ***/
523         for (i = 1; i <= l_query; ++i) {
524                 double sum = 0., *fi = f[i], *bi = b[i], max = 0.;
525                 int beg = 0, end = l_ref, x, max_k = -1;
526                 x = i - bw; beg = beg > x? beg : x;
527                 x = i + bw; end = end < x? end : x;
528                 for (k = beg; k <= end; ++k) {
529                         int u;
530                         double z;
531                         set_u(u, bw, i, k);
532                         z = fi[u+0] * bi[u+0]; if (z > max) max = z, max_k = k<<2 | 0; sum += z;
533                         z = fi[u+1] * bi[u+1]; if (z > max) max = z, max_k = k<<2 | 1; sum += z;
534                 }
535                 max /= sum; sum *= s[i]; // if everything works as is expected, sum == 1.0
536                 if (state) state[i-1] = max_k;
537                 if (q) q[i-1] = -4.343 * log(1. - max);
538 #ifdef _MAIN
539                 fprintf(stderr, "(%.10lg,%.10lg) (%d,%d:%d)~%lg\n", pb, sum, i, max_k>>2, max_k&3, max); // DEBUG
540 #endif
541         }
542         /*** free ***/
543         for (i = 0; i <= l_query; ++i) {
544                 free(f[i]); free(b[i]);
545         }
546         free(f); free(b); free(s);
547         return 0;
548 }
549
550 #ifdef _MAIN
551 int main()
552 {
553         int l_ref = 5, l_query = 4;
554         uint8_t *ref = (uint8_t*)"\0\1\3\3\1";
555         uint8_t *query = (uint8_t*)"\0\3\3\1";
556 //      uint8_t *query = (uint8_t*)"\1\3\3\1"; // FIXME: the output is not so right given this input!!!
557         static float qual[4] = {.01, .01, .01, .01};
558         ka_prob_glocal(ref, l_ref, query, l_query, qual, &ka_probpar_def, 0, 0);
559         return 0;
560 }
561 #endif