public static void crossProduct3D(Vector A, Vector B, Vector C) {
if (B.getData().equals(C.getData()))
throw new IllegalArgumentException("Inner data structures are the same.");
if (A.getLength() != 3 || B.getLength() != 3)
throw new IllegalArgumentException("Vectors should both be 3D vectors");
unCheckedCrossPorduct3D(A, B, C);
}
/**
* Returns the dot product of the two vectors. It's the user responsibility to make sure that each
* vector has the same dimensions.
*/
public static double unCheckedDotProduct(Vector A, Vector B) {
double result = 0;
double[] dataA = A.getData();
double[] dataB = B.getData();
for (int i = 0; i < A.getLength(); i++) result += dataA[i] * dataB[i];
return result;
}
/**
* Multiplies the matrix A with the vector B and stores the result in vector C, the inner data
* arrays of C may NOT be the same as the one in B (So be careful when using vectors from methods
* like {@link Vector.wrapAround()} or {@link Matrix.wrapAround()}).
*
* @throws IllegalArgumentException If the dimensions of A, B and C are illegal for a
* matrix-vector multiplication.
* @throws IllegalArgumentException If the inner data arrays of B and C are the same.
*/
public static void mult(Matrix A, Vector B, Vector C) {
if (B.getData().equals(C.getData()))
throw new IllegalArgumentException("Inner data structures are the same.");
if (A.getnCols() != B.getLength() || A.getnRows() != C.getLength())
throw new IllegalArgumentException("Illegal matrix dimensions.");
else unCheckedMult(A, B, C);
}
/**
* Multiplies the matrix A with the vector B and stores the result in vector C, the inner data
* arrays of C may NOT be the same as the one in B (So be careful when using vectors from methods
* like {@link Vector.wrapAround()} or {@link Matrix.wrapAround()}). It's the user responsibility
* to make sure that each vector has the same dimensions.
*/
public static void unCheckedMult(Matrix A, Vector B, Vector C) {
double[][] dataA = A.getData();
double[] dataB = B.getData();
double[] dataC = C.getData();
for (int j = 0; j < A.getnRows(); j++) {
for (int k = 0; k < A.getnCols(); k++) dataC[j] += dataA[k][j] * dataB[k];
}
}
/**
* Subtracts the vector B from the vector A and stores the result in vector C. It's the user
* responsibility to make sure that each vector has the same dimensions.
*/
public static void unCheckedSub(Vector A, Vector B, Vector C) {
double[] dataA = A.getData();
double[] dataB = B.getData();
double[] dataC = C.getData();
for (int i = 0; i < dataA.length; i++) dataC[i] = dataA[i] - dataB[i];
}
