Ax=B, Setting known values into the x array?

I use cusparse and cublas to solve Ax=B. In some problems, I know certain of x beforehand. And I’ve had some success by coding those known x values into the B array. I populate the A array, then the B array. Then I will modify the B array based off known values in the x array.

But I’m just curious - is there any way to tell cusparse/cublas to force certain values in x array and then let it solve the system without changing the B array?