Data commit

Task/Matrix-transposition/C/matrix-transposition-1.c

@@ -0,0 +1,25 @@
+#include <stdio.h>
+
+void transpose(void *dest, void *src, int src_h, int src_w)
+{
+	int i, j;
+	double (*d)[src_h] = dest, (*s)[src_w] = src;
+	for (i = 0; i < src_h; i++)
+		for (j = 0; j < src_w; j++)
+			d[j][i] = s[i][j];
+}
+
+int main()
+{
+	int i, j;
+	double a[3][5] = {{ 0, 1, 2, 3, 4 },
+			  { 5, 6, 7, 8, 9 },
+			  { 1, 0, 0, 0, 42}};
+	double b[5][3];
+	transpose(b, a, 3, 5);
+
+	for (i = 0; i < 5; i++)
+		for (j = 0; j < 3; j++)
+			printf("%g%c", b[i][j], j == 2 ? '\n' : ' ');
+	return 0;
+}

Task/Matrix-transposition/C/matrix-transposition-2.c

@@ -0,0 +1,50 @@
+#include <stdio.h>
+
+void transpose(double *m, int w, int h)
+{
+	int start, next, i;
+	double tmp;
+
+	for (start = 0; start <= w * h - 1; start++) {
+		next = start;
+		i = 0;
+		do {	i++;
+			next = (next % h) * w + next / h;
+		} while (next > start);
+		if (next < start || i == 1) continue;
+
+		tmp = m[next = start];
+		do {
+			i = (next % h) * w + next / h;
+			m[next] = (i == start) ? tmp : m[i];
+			next = i;
+		} while (next > start);
+	}
+}
+
+void show_matrix(double *m, int w, int h)
+{
+	int i, j;
+	for (i = 0; i < h; i++) {
+		for (j = 0; j < w; j++)
+			printf("%2g ", m[i * w + j]);
+		putchar('\n');
+	}
+}
+
+int main(void)
+{
+	int i;
+	double m[15];
+	for (i = 0; i < 15; i++) m[i] = i + 1;
+
+	puts("before transpose:");
+	show_matrix(m, 3, 5);
+
+	transpose(m, 3, 5);
+
+	puts("\nafter transpose:");
+	show_matrix(m, 5, 3);
+
+	return 0;
+}