fixing percentage error in monte_carlo.c (#374)

Gathros · leios · commit 38c58ac4d8a6 · 2018-09-12T07:00:59.000+09:00
diff --git a/contents/monte_carlo_integration/code/c/monte_carlo.c b/contents/monte_carlo_integration/code/c/monte_carlo.c
@@ -24,7 +24,7 @@ void monte_carlo(int samples) {
     double estimate = 4.0 * count / (samples * radius * radius);
 
     printf("The estimate of pi is %f\n", estimate);
-    printf("Which has an error of %0.2f%\n", 100 * (M_PI - estimate) / M_PI);
+    printf("Percentage error: %0.2f%\n", 100 * fabs(M_PI - estimate) / M_PI);
 }
 
 int main() {

Original file line number	Diff line number	Diff line change
`@@ -24,7 +24,7 @@ void monte_carlo(int samples) {`
`24`	`24`	`double estimate = 4.0 * count / (samples * radius * radius);`
`25`	`25`
`26`	`26`	`printf("The estimate of pi is %f\n", estimate);`
`27`		`- printf("Which has an error of %0.2f%\n", 100 * (M_PI - estimate) / M_PI);`
	`27`	`+ printf("Percentage error: %0.2f%\n", 100 * fabs(M_PI - estimate) / M_PI);`
`28`	`28`	`}`
`29`	`29`
`30`	`30`	`int main() {`