/*Program to calculate the detreminant of a sqaure matrix*/
#include<stdio.h>
//FUNCTION DEFINATION FOR MATIRX INPUT, DISPLAY AND DETERMINANT
//TIP FOR MATRIX INPUT & DISPLAY : HERE THE ROW AND COL ARE PASSED PRIOR TO THE MATRIX, BECAUSE IN CASE OF MATRIX, THE COLUMN FIELD IS MANDATORY SO, IT IS DECLARED FIRST AND USED IN THE MATRIX ITSELF
void matrix_input(int, float [][]);
void matrix_display(int, float [][]);
float matrix_determinant(int, float [][]);
//STARTING MAIN() FUNCTION
int main()
{
printf("\n\nPROGRAM TO CALCULATE THE DETERMINANT OF A SQUARE MATRIX\n\n");
//INITIALIZING ROW AND COL FOR BOTH THE MATRIX
int row,col;
float deterninamt;
printf("Enter the size of the matrix (row and col) : ");
scanf("%d%d",&row,&col);
//CHECKING OF THE MATRIX IS SQAURE OR NOT ??
//IF YES THEN THE MATRIXES ARE INITIALISED
if(row == col)
{
float matrix[row][col], determinant;
//GETTING INPUT FOR THE FIRST MARTIX | PASSING THE ROW, COL & MATRIX NAME
printf("\nEnter elements for MATRIX 1 (%dx%d), row-wise :",row,col);
matrix_input(row, matrix);
//CALLING THE DISPLAY_MATRIX FUNCTION : PASSING ROW, COL AND NAME OF MATRIX
printf("\nGiven matrix (%dx%d) :\n",row,col);
matrix_display(row, matrix);
determinant = matrix_determinant(row, matrix);
printf("\nAfter processing (%dx%d) :\n",row,col);
matrix_display(row, matrix);
printf("\n\nDeterminant = %f",determinant);
}
//DISPLAYING ERROR INCASE OF MIS-MATCH MATRIX SIZE
else
printf("\n\nFor calculating the determinant of a matrix, the martix must be a SQUARE MATRIX.");
printf("\n\n");
getch();
return 0;
}
//END OF MAIN FUNCTION
/*FUNCTION TO FILL A SQUARE MATRIX
PARAMTER: ROW, COL, MATRIX NAME | INCASE OF A SQUARE MATRIX, THE ROW AND COL ARE SAME, SO ONLY ONE VALUE IS PASSED TO REDUCE MEMORY CONSUMPTION,
ALSO THE COLUMN NAME OF THE MATRIX IS MANDATORY SO THE VARIABLE 'row' IS USED.*/
void matrix_input(int row, float matrix[][row])
{
int i,j,choice;
printf("\nChoose matrix filling type : \n\t1. Manual Fill\n\t2. Auto Fill (1-100)\n");
scanf("%d",&choice);
//MANUAL FILL | GETTING ELEMENT FROM KEYBORAD FEED BY THE USER
if(choice == 1)
{
//HERE ROWS AND COLS ARE EQUAL, SO 'row' IS USED IN BOTH THE LOOPS
for(i=0; i<row; i++)
for(j=0; j<row; j++)
{
printf("Enter element for row-%d, col-%d : ",i+1,j+1);
scanf("%f", &matrix[i][j]);
}
}
//AUTO FILL | GETTING ELEMENT GENERATED BY THE RAND()
else
{
for(i=0; i<row; i++)
for(j=0; j<row; j++)
{
choice = rand() % 10+1;
printf("Enter element for row-%d, col-%d : %d\n",i+1,j+1, choice);
matrix[i][j] = choice;
}
}
}
//END OF MATRIX_INPUT FUNCTION
/*FUNCTION TO DISPLAY A SQUARE SQUARE_MATRIX | INCASE OF A SQUARE MATRIX THE ROW AND COL ARE EQUAL, SO ONLY ONE PARAMETER IS USED*/
void matrix_display(int row, float matrix[][row])
{
//HERE ROWS AND COLS ARE EQUAL, SO 'row' IS USED IN BOTHETHE LOOPS
int i, j;
for(i=0; i<row; i++)
{
for(j=0; j<row; j++)
printf(" %5.2f ",matrix[i][j]);
printf("\n");
}
}
//END OF FUNCTION TO DISPLAY A SQUARE_MATRIX
/*FUNCTION TO CALCULATE THE DETERMINANT OF A MATRIX
PARAMETER : SINGLE VALUE OF ROW AND COL IS PASSED, AS FOR ALL THE MATRIX, THE VALUE OF ROW AND COL WILL BE SAME | IN ALL THE CASE THE COLOUMN VALUE IS MANDATORY SO ITS SET TO 'col', WHICH IS AGAIN PREDEFINED*/
float matrix_determinant(int row, float matrix[][row])
{
int i, j, k,flag=0,counter,count;
float determinant=0,temp,element;
for(i=0; i<row; i++)
{
flag=0;
for(j=0; j<row; j++)
{
//counter++;
if(i == j)
{
temp = 1 / matrix[i][j];
determinant = determinant + temp;
counter = i;
for(k=0; k<row; k++)
{
printf("\nRow-%d,Col-%d : %f = %f * %f ",i,k,matrix[i][k],matrix[i][k],temp);
matrix[i][k] = matrix[i][k] * temp;
}
break;
}
if((i>j) && (flag == 0))
{
temp = matrix[i][j];
printf("\n\nValue of the term to be multiplied : %f\n",temp);
for(k=0; k<row; k++)
{
printf("\nRow-%d,Col-%d : %f = %f - (%f * %f)",i,k,matrix[i][k],matrix[i][k],temp,matrix[counter][k]);
matrix[i][k] = matrix[i][k] - (temp * matrix[counter][k]);
}
printf("\n.........................................\n");
matrix_display(row, matrix);
flag = 1;
}
}
printf("\n-----------------------------------------\n");
matrix_display(row, matrix);
}
return determinant;
}
/