Question

I have some C code I am trying to translate into C# code and I’m running into pointers which I am not familiar with so I don’t know the C# equivalent. Get I get some help?

Case 1: Given these three lines in C, how do I declare p in C#?

double snorm[169];
double *p = snorm;
*p = 1.0;

Case 2: I have no idea what the pointers are actualy doing so I don’t know how to change this line to C#.

*(snorm+n) = *(snorm+n-1) * (double)(2*n-1) / (double)n;

Answer 1

First:

double[] snorm = new double[169];
snorm[0] = 1.0;

Than just use snorm instead of p.

Second:

snorm[n] = snorm[n-1] * (double)(2*n-1)/(double)n;

Basically *p means that you take the value at the address of memory, referenced by p. Incrementing and adding to the pointer are moving the pointer in memory, so p++, as well as (p+1) just refers to the next item in memory (how far it really moves in memory depends on the data type the pointer points to). And, *(p+n) is just a value of the n-th item in the array (if p points to an array)

Anyway, you should get yourself familiar with pointers.