Initialized pointer has all 0's instead of generated values

Question

I am implementing a sparse linear equation solver such as Lx = b. For this, I initialize a reference x vector named x_ref and generate an RHS vector b accordingly. However, both pointers seem empty somehow.

VALUE_TYPE is a macro and set to double

VALUE_TYPE *x_ref = (VALUE_TYPE *)malloc(sizeof(VALUE_TYPE) * n);
VALUE_TYPE *b = (VALUE_TYPE *)malloc(sizeof(VALUE_TYPE) * n);

for ( int i = 0; i < n; i++)
    x_ref[i] = rand() % 10 + 1;

for (int i = 0; i < n; i++)
    {
    for (int j = cscColPtrTR[i]; j < cscColPtrTR[i+1]; j++)
        {
            int rowid = cscRowIdxTR[j]; //printf("rowid = %i\n", rowid);
            b[rowid] += cscValTR[j] * x_ref[i];

        }
    }

After I print them as;

for(int i = 0; i < n; i++)
{
    printf("%d\t\t%d\n", x_ref[i], b[i]);
}

The results are:

4226166 1977719296
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0
0       0

I cannot understand what is wrong with it.

Answer 1

1. Rather use objects in the sizeof instead of types VALUE_TYPE *x_ref = (VALUE_TYPE *)malloc(sizeof(*x_ref) * n);
2. Use the correct printf formats. %d is used to output integers, not doubles.

#define VALUE_TYPE double
int main(void)
{
    size_t n = 20;
    VALUE_TYPE *x_ref = malloc(sizeof(*x_ref) * n);
    VALUE_TYPE *b = malloc(sizeof(*b) * n);

    for ( int i = 0; i < n; i++)
        x_ref[i] = rand() % 10 + 1;
    for ( int i = 0; i < n; i++)
        printf("%d - %f\n", i, x_ref[i]);
}

https://godbolt.org/z/RKjZi8