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  1. #include <stdio.h>
  2. #include <math.h>
  3. #include <mpi.h>
  4.  
  5. double function(double x) {
  6.   return sin(x);  // change this to the desired function
  7. }
  8.  
  9. int main(int argc, char *argv[]) {
  10.   int i, n, rank, size, local_n;
  11.   double a, b, h, x, sum = 0.0, local_sum = 0.0, total_sum = 0.0;
  12.  
  13.   MPI_Init(&argc, &argv);
  14.   MPI_Comm_rank(MPI_COMM_WORLD, &rank);
  15.   MPI_Comm_size(MPI_COMM_WORLD, &size);
  16.  
  17.   if (rank == 0) {
  18.     printf("Enter the lower limit (a): ");
  19.     scanf("%lf", &a);
  20.     printf("Enter the upper limit (b): ");
  21.     scanf("%lf", &b);
  22.     printf("Enter the number of intervals (n): ");
  23.     scanf("%d", &n);
  24.   }
  25.  
  26.   MPI_Bcast(&a, 1, MPI_DOUBLE, 0, MPI_COMM_WORLD);
  27.   MPI_Bcast(&b, 1, MPI_DOUBLE, 0, MPI_COMM_WORLD);
  28.   MPI_Bcast(&n, 1, MPI_INT, 0, MPI_COMM_WORLD);
  29.  
  30.   h = (b - a) / n;
  31.   local_n = n / size;
  32.  
  33.   for (i = 0; i < local_n; i++) {
  34.     x = a + (rank * local_n + i + 0.5) * h;
  35.     local_sum += function(x);
  36.   }
  37.   local_sum *= h;
  38.  
  39.   MPI_Reduce(&local_sum, &total_sum, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
  40.  
  41.   if (rank == 0) {
  42.     printf("The value of the integral is: %.6f\n", total_sum);
  43.   }
  44.  
  45.   MPI_Finalize();
  46.   return 0;
  47. }
  48.  
Success #stdin #stdout #stderr 0.26s 39024KB
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Standard input is empty
stdout
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Standard output is empty
stderr
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Error: unexpected 'function' in "double function"
Execution halted
https://ideone.com/YWnS83
language:
R (R 3.5.2)
created:
1 year ago
visibility:
public

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