v.a(); Note: this is inside a different class file to the method

this comes up when as an error

Cannot invoke a() on the primitive type float

heres the method:

 private void a(float af[][], int i)
    {
        float f1 = hy.c(af[i][0] * af[i][0] + af[i][1] * af[i][1] + af[i][2] * af[i][2]);
        af[i][0] /= f1;
        af[i][1] /= f1;
        af[i][2] /= f1;
        af[i][3] /= f1;
    }

do i just need to add paremeters to the invoke(v.a())?