X-Git-Url: https://git.donarmstrong.com/?p=fastq-tools.git;a=blobdiff_plain;f=src%2Ffastq-sample.c;fp=src%2Ffastq-sample.c;h=0adf02dd27c6d6d73c3c1ae08ddd36ec4729084b;hp=d3c2b550e3c128844d7df678764242a3d49c1be6;hb=a7a328a691ab370ed7fd61c9c04af9def02395d5;hpb=d6b81119e55cf77c1e4c17b9e9026abc01e22b96 diff --git a/src/fastq-sample.c b/src/fastq-sample.c index d3c2b55..0adf02d 100644 --- a/src/fastq-sample.c +++ b/src/fastq-sample.c @@ -8,23 +8,16 @@ * Sample reads with or without replacement from a FASTQ file. * */ +#include +#include +#include +#include +#include #include "common.h" #include "parse.h" #include "rng.h" -#include -#include -#include -#include -#include -#if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__) -# include -# include -# define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY) -#else -# define SET_BINARY_MODE(file) -#endif static const char* prog_name = "fastq-sample"; @@ -39,7 +32,7 @@ void print_help() "Options:\n" " -n N the number of reads to sample (default: 10000)\n" " -p N the proportion of the total reads to sample\n" -" -o, --output=PREFIX output file prefix\n" +" -o, --output=PREFIX output file prefix\n (Default: \"sample\")" " -c, --complement-output=PREFIX\n" " output reads not included in the random sample to\n" " a file (or files) with the given prefix (by default,\n" @@ -48,7 +41,7 @@ void print_help() " -s, --seed=SEED a manual seed to the random number generator\n" " -h, --help print this message\n" " -V, --version output version information and exit\n" - ); +); } @@ -103,25 +96,25 @@ unsigned long* index_without_replacement(rng_t* rng, unsigned long n) void fastq_sample(unsigned long rng_seed, - const char* prefix, const char* cprefix, - FILE* file1, FILE* file2, unsigned long k, double p) + const char* prefix, const char* cprefix, + FILE* file1, FILE* file2, unsigned long k, double p) { - /* - * The basic idea is this: - * - * 1. Count the number of lines in the file, n. - * - * 2a. If sampling with replacement, generate k random integers in [0, n-1]. - * - * 2b. If sampling without replacement, generate a list of integers 0..(n-1), - * shuffle with fisher-yates, then consider the first k. - * - * 3. Sort the integer list. - * - * 3. Read through the file again, when the number at the front of the integer - * list matches the index of the fastq etry, print the entry, and pop the - * number. - */ + /* + * The basic idea is this: + * + * 1. Count the number of lines in the file, n. + * + * 2a. If sampling with replacement, generate k random integers in [0, n-1]. + * + * 2b. If sampling without replacement, generate a list of integers 0..(n-1), + * shuffle with fisher-yates, then consider the first k. + * + * 3. Sort the integer list. + * + * 3. Read through the file again, when the number at the front of the integer + * list matches the index of the fastq etry, print the entry, and pop the + * number. + */ unsigned long n, n2; @@ -142,7 +135,7 @@ void fastq_sample(unsigned long rng_seed, if (f2 != NULL) fastq_rewind(f2); if (p > 0.0) { - k = (unsigned long) (p * (double) n); + k = (unsigned long) round(p * (double) n); if (!replacement_flag && k > n) k = n; } @@ -155,7 +148,6 @@ void fastq_sample(unsigned long rng_seed, qsort(xs, k, sizeof(unsigned long), cmpul); - /* open output */ FILE* fout1; FILE* fout2; @@ -167,7 +159,7 @@ void fastq_sample(unsigned long rng_seed, output_name = malloc_or_die((output_len + 1) * sizeof(char)); snprintf(output_name, output_len, "%s.fastq", prefix); - fout1 = fopen(output_name, "wb"); + fout1 = open_without_clobber(output_name); if (fout1 == NULL) { fprintf(stderr, "Cannot open file %s for writing.\n", output_name); exit(1); @@ -182,14 +174,14 @@ void fastq_sample(unsigned long rng_seed, output_name = malloc_or_die((output_len + 1) * sizeof(char)); snprintf(output_name, output_len, "%s.1.fastq", prefix); - fout1 = fopen(output_name, "wb"); + fout1 = open_without_clobber(output_name); if (fout1 == NULL) { fprintf(stderr, "Cannot open file %s for writing.\n", output_name); exit(1); } snprintf(output_name, output_len, "%s.2.fastq", prefix); - fout2 = fopen(output_name, "wb"); + fout1 = open_without_clobber(output_name); if (fout1 == NULL) { fprintf(stderr, "Cannot open file %s for writing.\n", output_name); exit(1); @@ -198,7 +190,6 @@ void fastq_sample(unsigned long rng_seed, free(output_name); } - /* open complement output */ FILE* cfout1 = NULL; FILE* cfout2 = NULL; @@ -239,8 +230,6 @@ void fastq_sample(unsigned long rng_seed, free(output_name); } - - unsigned long i = 0; // read number unsigned long j = 0; // index into xs @@ -290,21 +279,17 @@ void fastq_sample(unsigned long rng_seed, int main(int argc, char* argv[]) { - SET_BINARY_MODE(stdin); - SET_BINARY_MODE(stdout); - int opt; int opt_idx; - const char* prefix = NULL; - const char* cprefix = NULL; + const char* prefix = "sample"; + const char* cprefix = NULL; unsigned long rng_seed = 4357; unsigned long k = 10000; // number of reads to sample double p = -1; // proportion of reads to sample - static struct option long_options[] = - { + { {"with-replacement", no_argument, NULL, 'r'}, {"complement-output", required_argument, NULL, 'c'}, {"seed", required_argument, NULL, 's'}, @@ -375,60 +360,28 @@ int main(int argc, char* argv[]) FILE* file1 = NULL; FILE* file2 = NULL; - char* prefix_alloc = NULL; - if (optind >= argc) { fputs("An input file must be given.\n", stderr); print_help(); - exit(1); + return EXIT_FAILURE; } - else { - file1 = fopen(argv[optind], "rb"); - if (file1 == NULL) { - fprintf(stderr, "Cannot open '%s' for reading.\n", argv[optind]); - return 1; - } - if (prefix == NULL) { - /* guess at a reasonable output refix by trimming the - * trailing file extension, if any. */ - char* tmp; - - /* base name */ - tmp = strrchr(argv[optind], '/'); - if (tmp != NULL) argv[optind] = tmp + 1; - - /* exclude file suffixes */ - tmp = strchr(argv[optind], '.'); - if (tmp == NULL) prefix = argv[optind]; - else { - prefix_alloc = malloc_or_die((tmp - argv[optind] + 1) * sizeof(char)); - memcpy(prefix_alloc, argv[optind], (tmp - argv[optind]) * sizeof(char)); - prefix_alloc[tmp - argv[optind]] = '\0'; - prefix = prefix_alloc; - } - } - ++optind; + file1 = fopen(argv[optind], "rb"); + if (file1 == NULL) { + fprintf(stderr, "Cannot open '%s' for reading.\n", argv[optind]); + return 1; + } - if (optind < argc) { - file2 = fopen(argv[optind], "rb"); - if (file2 == NULL) { - fprintf(stderr, "Cannot open '%s' for reading.\n", argv[optind]); - return 1; - } + if (++optind < argc) { + file2 = fopen(argv[optind], "rb"); + if (file2 == NULL) { + fprintf(stderr, "Cannot open '%s' for reading.\n", argv[optind]); + return 1; } } fastq_sample(rng_seed, prefix, cprefix, file1, file2, k, p); - free(prefix_alloc); - return 0; + return EXIT_SUCCESS; } - - - - - - -