* Added Brent's method for frequency estimate

[samtools.git] / bcftools / main.c

diff --git a/bcftools/main.c b/bcftools/main.c
index 7ffc2a05f4557a1aa12a156a86dc2e15cf51ead3..07d9e93de8fa102a5453adfd5279195a813f72d2 100644 (file)
--- a/bcftools/main.c
+++ b/bcftools/main.c
@@ -42,6 +42,50 @@ int bcf_cat(int n, char * const *fn)
        return 0;
 }
 
+int bcf_main_pwld(int argc, char *argv[])
+{
+       extern double bcf_pair_freq(const bcf1_t *b0, const bcf1_t *b1, double f[4]);
+       bcf_t *fp;
+       bcf_hdr_t *h;
+       bcf1_t **b, *b0;
+       int i, j, m, n;
+       double f[4];
+       if (argc == 1) {
+               fprintf(stderr, "Usage: bcftools pwld <in.bcf>\n");
+               return 1;
+       }
+       fp = bcf_open(argv[1], "rb");
+       h = bcf_hdr_read(fp);
+       // read the entire BCF
+       m = n = 0; b = 0;
+       b0 = calloc(1, sizeof(bcf1_t));
+       while (bcf_read(fp, h, b0) >= 0) {
+               if (m == n) {
+                       m = m? m<<1 : 16;
+                       b = realloc(b, sizeof(void*) * m);
+               }
+               b[n] = calloc(1, sizeof(bcf1_t));
+               bcf_cpy(b[n++], b0);
+       }
+       bcf_destroy(b0);
+       // compute pair-wise r^2
+       printf("%d\n", n); // the number of loci
+       for (i = 0; i < n; ++i) {
+               printf("%s:%d", h->ns[b[i]->tid], b[i]->pos + 1);
+               for (j = 0; j < i; ++j) {
+                       double r = bcf_pair_freq(b[i], b[j], f);
+                       printf("\t%.3f", r*r);
+               }
+               printf("\t1.000\n");
+       }
+       // free
+       for (i = 0; i < n; ++i) bcf_destroy(b[i]);
+       free(b);
+       bcf_hdr_destroy(h);
+       bcf_close(fp);
+       return 0;
+}
+
 int main(int argc, char *argv[])
 {
        if (argc == 1) {
@@ -50,12 +94,14 @@ int main(int argc, char *argv[])
                fprintf(stderr, "Command: view      print, extract, convert and call SNPs from BCF\n");
                fprintf(stderr, "         index     index BCF\n");
                fprintf(stderr, "         cat       concatenate BCFs\n");
+               fprintf(stderr, "         ld        compute all-pair r^2\n");
                fprintf(stderr, "\n");
                return 1;
        }
        if (strcmp(argv[1], "view") == 0) return bcfview(argc-1, argv+1);
        else if (strcmp(argv[1], "index") == 0) return bcf_main_index(argc-1, argv+1);
-       else if (strcmp(argv[1], "cat") == 0) return bcf_cat(argc-2, argv+2);
+       else if (strcmp(argv[1], "ld") == 0) return bcf_main_pwld(argc-1, argv+1);
+       else if (strcmp(argv[1], "cat") == 0) return bcf_cat(argc-2, argv+2); // cat is different ...
        else {
                fprintf(stderr, "[main] Unrecognized command.\n");
                return 1;