//this file contains Vector and Matrix io functions

#include "Header.h"

//reads a vector from a stream
//
//returns Vec pointer at success
//returns 0 if failed to read (can be used to know EOF for example)
Vec * readVec(FILE * vecInFile)
{
	int vectorSize, i;
	//if falied to read, return 0
	if(fscanf(vecInFile, "%d", &vectorSize) == EOF)
		return 0;
	//validate vector size
	if(vectorSize <= 0)
	{
		printf("invalid vector format");
		exit(1);
	}
	
	//create vector of size vectorSize
	Vec * vecP = createVec(vectorSize);
	
	//read to vector's float array
	for(i =0; i < vectorSize; i++)
	{
		fscanf(vecInFile, "%f", &(vecP->p[i]));
	}
	return vecP;
}
//prints out vector's values to a stream
void writeVec(Vec * vecWriteP, FILE * outFile)
{
	int i;
	fprintf(outFile, "%d\n", vecWriteP->n);
	for(i =0; i < vecWriteP->n; i++)
	{
		fprintf(outFile, "%g\n", vecWriteP->p[i]);
	}
}

//reades a matrix from a stream
//
//returns Mat pointer at success
//returns 0 if failed to read (can be used to know EOF for example)
Mat * readMat(FILE * matInFile)
{
	//n: number of rows. m: number of columns.
	int n, m, i;
	//if falied to read, return 0
	if(fscanf(matInFile, "%d", &n) == EOF)
		return 0;
	fscanf(matInFile, "%d", &m);
	
	//validate matrix size
	if(n <= 0 || m <= 0)
	{
		printf("invalid matrix format");
		exit(1);
	}
	
	//create matrix of size n, m
	Mat * matP = createMat(n, m);
	
	//read to matrix's float array
	for(i =0; i < n*m; i++)
	{
		fscanf(matInFile, "%f", &(matP->p[i]));
	}
	return matP;
}

//prints out matrix values to a stream
void writeMat(Mat * matP, FILE * outFile)
{
	int i;
	fprintf(outFile, "%d\t%d\n", matP->n, matP->m);
	
	for(i =0; i < (matP->n*matP->m); i++)
	{
		fprintf(outFile, "%g\n", matP->p[i]);
	}
}