Question

For C program, convert the 1-D stencil program from lab03 to use array reference (B[I]) to access array element instead of using pointers. The C program follows these steps: 1) declare two arrays, each has 100 elements; 2) use a for loop to randomly generate 100 integers and store them in one array; 3) use another for loop to do the 1-D stencil and store the result in the other array;

Answer 1

A stencil pattern is a map where each output depends on a “neighborhood” of inputs.

A stencil output is a function of a “neighborhood” of elements in an input collection.

C program:

1) declare two arrays, each has 100 elements;

#include <stdio.h>
#include <stdlib.h>
int main(void)
{
   int randArray[100],stencilArray[100],i;

2) use a for loop to randomly generate 100 integers and store them in one array;

for(i=0;i<100;i++)
     randArray[i]=rand();   
   

printing the random elements from the array

printf("\nElements of the array::");
   for(i=0;i<100;i++)
   {
     printf("\nElement number %d::%d",i+1,randArray[i]);
   }

3) use another for loop to do the 1-D stencil and store the result in the other array;

for (i =0; i < 100 ; ++i )
   {
       stencilArray[i] = 0.25f * stencilArray[i-1] + 0.50f * stencilArray[i] + 0.25f * stencilArray[i+1];
   }

print the 1D stencil array

printf("\n1D Stencil of the random array::");
   for(i=0;i<100;i++)
   {
    printf("\n%d::%d",i+1,stencilArray[i]);
   }
   return 0;
}

Output:

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