I am using cudaMalloc and cudaMemcpy to allocate a matrix and copy into it arrays of vectors , like this:

```
float **pa;    
cudaMalloc((void***)&pa,  N*sizeof(float*)); //this seems to be ok
for(i=0; i<N; i++) {
    cudaMalloc((void**) &(pa[i]), N*sizeof(float)); //this gives seg fault
    cudaMemcpy (pa[i], A[i], N*sizeof(float), cudaMemcpyHostToDevice); // also i am not sure about this
}

```

What is wrong with my instructions?
Thanks in advance

P.S. A[i] is a vector

---

Now i'm trying to copy a matrix from the Device to a matrix from the host:

Supposing I have \*\*pc in the device, and \*\*pgpu is in the host:

```
cudaMemcpy (pgpu, pc, N*sizeof(float*), cudaMemcpyDeviceToHost);
for (i=0; i<N; i++)
    cudaMemcpy(pgpu[i], pc[i], N*sizeof(float), cudaMemcpyDeviceToHost);

```

= is wrong....