Introduction
cuBLAS Library DU-06702-001_v11.8|3
The legacy cuBLAS API, explained in more detail in the Appendix A, can be used by including
the header file “cublas.h”. Since the legacy API is identical to the previously released cuBLAS
library API, existing applications will work out of the box and automatically use this legacy API
without any source code changes.
The current and the legacy cuBLAS APIs cannot be used simultaneously in a single translation
unit: including both “cublas.h” and “cublas_v2.h” header files will lead to compilation
errors due to incompatible symbol redeclarations.
In general, new applications should not use the legacy cuBLAS API, and existing applications
should convert to using the new API if it requires sophisticated and optimal stream
parallelism, or if it calls cuBLAS routines concurrently from multiple threads.
For the rest of the document, the new cuBLAS Library API will simply be referred to as the
cuBLAS Library API.
As mentioned earlier the interfaces to the legacy and the cuBLAS library APIs are the header
file “cublas.h” and “cublas_v2.h”, respectively. In addition, applications using the cuBLAS
library need to link against:
‣
The DSO cublas.so for Linux,
‣
The DLL cublas.dll for Windows, or
‣
The dynamic library cublas.dylib for Mac OS X.
Note: The same dynamic library implements both the new and legacy cuBLAS APIs.
1.3. Example Code
The following code examples show an application written in C using the cuBLAS library API
with two indexing styles. Example 1 shows 1-based indexing and Example 2 shows 0-based
indexing.
//Example 1. Application Using C and cuBLAS: 1-based indexing
//-----------------------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <cuda_runtime.h>
#include "cublas_v2.h"
#define M 6
#define N 5
#define IDX2F(i,j,ld) ((((j)-1)*(ld))+((i)-1))
static __inline__ void modify (cublasHandle_t handle, float *m, int ldm, int n, int
p, int q, float alpha, float beta){
cublasSscal (handle, n-q+1, &alpha, &m[IDX2F(p,q,ldm)], ldm);
cublasSscal (handle, ldm-p+1, &beta, &m[IDX2F(p,q,ldm)], 1);
}
int main (void){
cudaError_t cudaStat;
cublasStatus_t stat;
cublasHandle_t handle;
