-
Notifications
You must be signed in to change notification settings - Fork 1
/
SerialRelaxation.c
97 lines (71 loc) · 2.39 KB
/
SerialRelaxation.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <sys/time.h>
// size of grid
#define COLUMNS 1000
#define ROWS 1000
#define MAX_TEMP_ERROR 0.01
double Temperature[ROWS+2][COLUMNS+2];
double Temperature_last[ROWS+2][COLUMNS+2];
void initialize();
void track_progress(int iter);
int main(int argc, char *argv[]) {
int i, j;
int max_iterations = 10000;
int iteration=1;
double dt=100;
struct timeval start_time, stop_time, elapsed_time;
gettimeofday(&start_time,NULL);
initialize();
while ( dt > MAX_TEMP_ERROR && iteration <= max_iterations ) {
for(i = 1; i <= ROWS; i++) {
for(j = 1; j <= COLUMNS; j++) {
Temperature[i][j] = 0.25 * (Temperature_last[i+1][j] + Temperature_last[i-1][j] +
Temperature_last[i][j+1] + Temperature_last[i][j-1]);
}
}
dt = 0.0;
for(i = 1; i <= ROWS; i++){
for(j = 1; j <= COLUMNS; j++){
dt = fmax( fabs(Temperature[i][j]-Temperature_last[i][j]), dt);
Temperature_last[i][j] = Temperature[i][j];
}
}
// Print sample values every 100 iterations
if((iteration % 100) == 0) {
track_progress(iteration);
}
iteration++;
}
gettimeofday(&stop_time,NULL);
timersub(&stop_time, &start_time, &elapsed_time);
printf("\nMax error at iteration %d was %f\n", iteration-1, dt);
printf("Total time was %f seconds.\n", elapsed_time.tv_sec+elapsed_time.tv_usec/1000000.0);
return 0;
}
void initialize(){
int i,j;
for(i = 0; i <= ROWS+1; i++){
for (j = 0; j <= COLUMNS+1; j++){
Temperature_last[i][j] = 0.0;
}
}
for(i = 0; i <= ROWS+1; i++) {
Temperature_last[i][0] = 0.0;
Temperature_last[i][COLUMNS+1] = (100.0/ROWS)*i;
}
for(j = 0; j <= COLUMNS+1; j++) {
Temperature_last[0][j] = 0.0;
Temperature_last[ROWS+1][j] = (100.0/COLUMNS)*j;
}
}
// print diagonal sample from bottom right corner
void track_progress(int iteration) {
int i;
printf("---------- Iteration number: %d ------------\n", iteration);
for(i = ROWS-5; i <= ROWS; i++) {
printf("[%d,%d]: %5.2f ", i, i, Temperature[i][i]);
}
printf("\n");
}