memcpy一段内存到std::vector

void *pData = malloc(sizeof(double)*xsize*ysize*1/8);
memset(pData,0x00,sizeof(double)*szize*ysize*1/8);
...
/*do something and give some values to some pixels*/
...
std::vector<double> resultVec(xsize*ysize);
memcpy((void*)&resultVec[0],pData,sizeof(double)*xsize*ysize);