Quaternion type: Difference between revisions

=={{header|Dart}}==

{{trans|Kotlin}}

<syntaxhighlight lang="Dart">

import 'dart:math' as math;

class Quaternion {

final double a, b, c, d;

Quaternion(this.a, this.b, this.c, this.d);

Quaternion operator +(Object other) {

if (other is Quaternion) {

return Quaternion(a + other.a, b + other.b, c + other.c, d + other.d);

} else if (other is double) {

return Quaternion(a + other, b, c, d);

}

throw ArgumentError('Invalid type for addition: ${other.runtimeType}');

}

Quaternion operator *(Object other) {

if (other is Quaternion) {

return Quaternion(

a * other.a - b * other.b - c * other.c - d * other.d,

a * other.b + b * other.a + c * other.d - d * other.c,

a * other.c - b * other.d + c * other.a + d * other.b,

a * other.d + b * other.c - c * other.b + d * other.a,

);

} else if (other is double) {

return Quaternion(a * other, b * other, c * other, d * other);

}

throw ArgumentError('Invalid type for multiplication: ${other.runtimeType}');

}

Quaternion operator -() => Quaternion(-a, -b, -c, -d);

Quaternion conj() => Quaternion(a, -b, -c, -d);

double norm() => math.sqrt(a * a + b * b + c * c + d * d);

@override

String toString() => '($a, $b, $c, $d)';

}

void main() {

var q = Quaternion(1.0, 2.0, 3.0, 4.0);

var q1 = Quaternion(2.0, 3.0, 4.0, 5.0);

var q2 = Quaternion(3.0, 4.0, 5.0, 6.0);

var r = 7.0;

print("q = $q");

print("q1 = $q1");

print("q2 = $q2");

print("r = $r\n");

print("norm(q) = ${q.norm().toStringAsFixed(6)}");

print("-q = ${-q}");

print("conj(q) = ${q.conj()}\n");

print("r + q = ${q + r}");

print("q + r = ${q + r}");

print("q1 + q2 = ${q1 + q2}\n");

print("r * q = ${q * r}");

print("q * r = ${q * r}");

var q3 = q1 * q2;

var q4 = q2 * q1;

print("q1 * q2 = $q3");

print("q2 * q1 = $q4\n");

print("q1 * q2 != q2 * q1 = ${q3 != q4}");

}

</syntaxhighlight>

{{out}}

<pre>

q = (1.0, 2.0, 3.0, 4.0)

q1 = (2.0, 3.0, 4.0, 5.0)

q2 = (3.0, 4.0, 5.0, 6.0)

r = 7.0

norm(q) = 5.477226

-q = (-1.0, -2.0, -3.0, -4.0)

conj(q) = (1.0, -2.0, -3.0, -4.0)

r + q = (8.0, 2.0, 3.0, 4.0)

q + r = (8.0, 2.0, 3.0, 4.0)

q1 + q2 = (5.0, 7.0, 9.0, 11.0)

r * q = (7.0, 14.0, 21.0, 28.0)

q * r = (7.0, 14.0, 21.0, 28.0)

q1 * q2 = (-56.0, 16.0, 24.0, 26.0)

q2 * q1 = (-56.0, 18.0, 20.0, 28.0)

q1 * q2 != q2 * q1 = true

</pre>