--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/chromeister/src/reverseComplement.c	Wed Dec 12 07:18:40 2018 -0500
@@ -0,0 +1,124 @@
+/* reverseComplement.c
+   Program reading a FASTA file as input (one or multiple sequence)
+   and then returning the reverse complementary sequence in the output file.
+   It is important to note that for multiple sequence file the first input
+   sequence is the last one at the output file and the last one in the input
+   is the first one in the output.
+   oscart@uma.es
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <inttypes.h>
+#include "commonFunctions.h"
+
+#define SEQSIZE 2000000000
+#define READINPUT 10000
+#define WSIZE 32
+#define NREADS 1000000
+
+int main(int ac, char** av) {
+	FILE *fIn, *fOut;
+	int64_t i, j, nR, seqLen = 0;
+	char *seq, c, toW;
+	long *offset = NULL;
+
+	if (ac != 3)
+		terror("USE: reverseComplement seqFile.IN reverseComplementarySeq.OUT");
+
+	/**
+	 * Allocating memory for the sequence
+	 * Fixed amount of memory, change it to loadSeqDB?
+	 */
+	if ((seq = (char*) malloc(SEQSIZE)) == NULL)
+		terror("memory for Seq");
+
+	if ((fIn = fopen(av[1], "rt")) == NULL)
+		terror("opening IN sequence FASTA file");
+
+	if ((fOut = fopen(av[2], "wt")) == NULL)
+		terror("opening OUT sequence Words file");
+	
+	if ((offset = (long *) malloc(sizeof(long)*NREADS)) == NULL)
+		terror("memory for offsets");
+
+	for(i=0;i<NREADS;i++){
+		offset[i]=0;
+	}
+
+	nR = 0;
+	c = fgetc(fIn);
+	while(!feof(fIn)){
+		if(c == '>'){
+			offset[nR++] = ftell(fIn)-1;
+		}
+		c = fgetc(fIn);
+	}
+
+	for(i=nR-1; i>=0; i--){
+		fseek(fIn, offset[i], SEEK_SET);
+		//READ and write header
+		if(fgets(seq, READINPUT, fIn)==NULL){
+			terror("Empty file");
+		}
+		fprintf(fOut, "%s", seq);
+		//READ and write sequence
+		c = fgetc(fIn);
+		while(c != '>' && !feof(fIn)){
+			if(isupper(c) || islower(c)){
+				seq[seqLen++]=c;
+			}
+			c = fgetc(fIn);
+		}
+		for(j=seqLen-1; j >= 0; j--){
+			switch(seq[j]){
+				case 'A':
+					toW = 'T';
+					break;
+				case 'C':
+					toW = 'G';
+					break;
+				case 'G':
+					toW = 'C';
+					break;
+				case 'T':
+					toW = 'A';
+					break;
+				case 'U':
+					toW = 'A';
+					break;
+				case 'a':
+					toW = 't';
+					break;
+				case 'c':
+					toW = 'g';
+					break;
+				case 'g':
+					toW = 'c';
+					break;
+				case 't':
+					toW = 'a';
+					break;
+				case 'u':
+					toW = 'a';
+					break;
+				default:
+					toW = seq[j];
+					break;
+			}
+			fwrite(&toW, sizeof(char), 1, fOut);
+		}
+		toW='\n';
+		fwrite(&toW, sizeof(char), 1, fOut);
+		seqLen=0;
+	}
+
+	fclose(fIn);
+	fclose(fOut);
+
+	return 0;
+}
+
+