Task 7 was corrected

2025.03.28/08Ex/matrix.c

@@ -0,0 +1,73 @@
+#include "matrix.h"
+#include <math.h>
+
+void init_vec_b(const double * restrict a, double * restrict b, int n)
+{
+	#pragma omp parallel for
+	for (int i = 0; i < n; ++i)
+	{
+		double sum = 0;
+
+		#pragma omp simd reduction(+:sum)
+		for (int k = 0; k < n; k+=2)
+			sum += a[i * n + k];
+
+		b[i] = sum;
+	}
+}
+
+void matvec_mul(int n, const double * restrict A, const double * restrict x, double * restrict x_k)
+{
+	#pragma	omp parallel for
+	for (int i = 0; i < n; i++)
+	{
+		double sum = 0;
+		#pragma omp simd reduction(+:sum)
+		for (int j = 0; j < n; j++)
+			sum += A[i * n + j] * x[j];
+		x_k[i] = sum;
+	}	
+}
+
+double get_r1(const double * restrict A, const double * restrict x_k, const double * restrict b, int n)
+{
+	double norm_r1x_1 = 0;
+	double residual_norm_1 = 0;
+	double r1 = 0;
+
+	#pragma omp parallel for reduction(+:residual_norm_1, norm_r1x_1)
+	for (int i = 0; i < n; ++i)
+	{
+		double bi = b[i];
+		double sum = 0;
+		
+		#pragma omp simd reduction(+:sum)
+		for (int j = 0; j < n; ++j)
+			sum += A[i*n + j] * x_k[j];
+		
+		residual_norm_1 += fabs(sum - bi);
+		norm_r1x_1 += fabs(bi);
+	}
+
+	r1 = residual_norm_1 / norm_r1x_1;
+
+	return r1;
+}
+
+double get_r2_value(const double * restrict x_k, int n)
+{
+	double relative_error = 0;
+	double total_diff = 0;
+	double template_sum = 0;
+
+	#pragma omp parallel for reduction(+:total_diff, template_sum)
+	for (int i = 0; i < n; ++i)
+	{
+		short int modi = i ^ 1;
+		total_diff += fabs(x_k[i] - modi);
+		template_sum += modi;
+	}
+
+	relative_error = total_diff / template_sum;
+	return relative_error;
+}