/*
Returns the dot product of two one dimensional arrays
Panics if either of the arrays is not one dimensional or if the lengths are not equal
*/
func Dot(x, y *GsArray) float64 {
if len(x.shape) > 2 || len(y.shape) > 2 {
panic("Invalid dimension for dot product!!")
}
if len(x.shape) == 2 && len(y.shape) == 2 {
if x.shape[0] != 1 && x.shape[1] != 1 {
if y.shape[0] != 1 && y.shape[1] != 1 {
panic("Invalid dimension for dot product!!")
}
}
} else if len(x.shape) == 1 && len(y.shape) == 2 {
if (y.shape[0] != 1) && (y.shape[1] != 1) {
panic("Invalid dimension for dot product!!")
}
} else if len(x.shape) == 2 && len(y.shape) == 1 {
if (x.shape[0] != 1) && (x.shape[1] != 1) {
panic("Invalid dimension for dot product!!")
}
}
if len(x.data) != len(y.data) {
panic("Vectors must be of the same lenght!!")
}
c_N := C.int(len(x.data))
c_x := (*C.double)(unsafe.Pointer(&x.data[0]))
c_incX := C.int(1)
c_y := (*C.double)(unsafe.Pointer(&y.data[0]))
c_incY := C.int(1)
return float64(C.cblas_ddot(c_N, c_x, c_incX, c_y, c_incY))
}
/*
double cblas_ddot(const int N, const double *X, const int incX, const double *Y, const int incY);
*/
func Ddot(x, y []float64) float64 {
if len(x) != len(y) {
panic("slices' size differ")
}
c_N := C.int(len(x))
c_X := (*C.double)(unsafe.Pointer(&x[0]))
c_incX := C.int(1)
c_Y := (*C.double)(unsafe.Pointer(&y[0]))
c_incY := C.int(1)
return float64(
C.cblas_ddot(c_N,
c_X, c_incX,
c_Y, c_incY))
}
// Dot product of v & o
func (v vector) dot(o vector) float64 {
c1 := (*C.double)(unsafe.Pointer(&v[0]))
c2 := (*C.double)(unsafe.Pointer(&o[0]))
return float64(C.cblas_ddot(C.int(len(v)), c1, 1, c2, 1))
}