Orbital elements: Difference between revisions
Rename Perl 6 -> Raku, alphabetize, minor clean-up
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Thundergnat (talk | contribs) (Rename Perl 6 -> Raku, alphabetize, minor clean-up) |
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Speed : (-0.55277084096044382, 0.95742708317976177, 0)
</pre>
=={{header|C sharp|C#}}==
{{trans|D}}
<lang csharp>using System;
namespace OrbitalElements {
class Vector {
public Vector(double x, double y, double z) {
X = x;
Y = y;
Z = z;
}
public double X { get; set; }
public double Y { get; set; }
public double Z { get; set; }
public double Abs() {
return Math.Sqrt(X * X + Y * Y + Z * Z);
}
public static Vector operator +(Vector lhs, Vector rhs) {
return new Vector(lhs.X + rhs.X, lhs.Y + rhs.Y, lhs.Z + rhs.Z);
}
public static Vector operator *(Vector self, double m) {
return new Vector(self.X * m, self.Y * m, self.Z * m);
}
public static Vector operator /(Vector self, double m) {
return new Vector(self.X / m, self.Y / m, self.Z / m);
}
public override string ToString() {
return string.Format("({0}, {1}, {2})", X, Y, Z);
}
}
class Program {
static Tuple<Vector, Vector> OrbitalStateVectors(
double semiMajorAxis,
double eccentricity,
double inclination,
double longitudeOfAscendingNode,
double argumentOfPeriapsis,
double trueAnomaly
) {
Vector mulAdd(Vector v1, double x1, Vector v2, double x2) {
return v1 * x1 + v2 * x2;
}
Tuple<Vector, Vector> rotate(Vector iv, Vector jv, double alpha) {
return new Tuple<Vector, Vector>(
mulAdd(iv, +Math.Cos(alpha), jv, Math.Sin(alpha)),
mulAdd(iv, -Math.Sin(alpha), jv, Math.Cos(alpha))
);
}
var i = new Vector(1, 0, 0);
var j = new Vector(0, 1, 0);
var k = new Vector(0, 0, 1);
var p = rotate(i, j, longitudeOfAscendingNode);
i = p.Item1; j = p.Item2;
p = rotate(j, k, inclination);
j = p.Item1;
p = rotate(i, j, argumentOfPeriapsis);
i = p.Item1; j = p.Item2;
var l = semiMajorAxis * ((eccentricity == 1.0) ? 2.0 : (1.0 - eccentricity * eccentricity));
var c = Math.Cos(trueAnomaly);
var s = Math.Sin(trueAnomaly);
var r = l / (1.0 + eccentricity * c);
var rprime = s * r * r / l;
var position = mulAdd(i, c, j, s) * r;
var speed = mulAdd(i, rprime * c - r * s, j, rprime * s + r * c);
speed /= speed.Abs();
speed *= Math.Sqrt(2.0 / r - 1.0 / semiMajorAxis);
return new Tuple<Vector, Vector>(position, speed);
}
static void Main(string[] args) {
var res = OrbitalStateVectors(1.0, 0.1, 0.0, 355.0 / (113.0 * 6.0), 0.0, 0.0);
Console.WriteLine("Position : {0}", res.Item1);
Console.WriteLine("Speed : {0}", res.Item2);
}
}
}</lang>
{{out}}
<pre>Position : (0.77942284339868, 0.450000034653684, 0)
Speed : (-0.552770840960444, 0.957427083179762, 0)</pre>
=={{header|C++}}==
Line 219 ⟶ 311:
<pre>Position : (0.779423, 0.45, 0)
Speed : (-0.552771, 0.957427, 0)</pre>
=={{header|D}}==
Line 618:
Speed : (-0.5527708409604438, 0.9574270831797618, 0.0)
</pre>
=={{header|Kotlin}}==
Line 883 ⟶ 882:
};</pre>
=={{header|Phix}}==
{{trans|Python}}
Line 1,049 ⟶ 1,000:
?-</pre>
=={{header|Python}}==
Line 1,114 ⟶ 1,064:
<pre>Position : (0.787295801413, 0.454545489549, 0.0)
Speed : (-0.547722599684, 0.948683273698, 0.0)</pre>
=={{header|Raku}}==
(formerly Perl 6)
We'll use the [https://github.com/grondilu/clifford Clifford geometric algebra library] but only for the vector operations.
<lang perl6>sub orbital-state-vectors(
Real :$semimajor-axis where * >= 0,
Real :$eccentricity where * >= 0,
Real :$inclination,
Real :$longitude-of-ascending-node,
Real :$argument-of-periapsis,
Real :$true-anomaly
) {
use Clifford;
my ($i, $j, $k) = @e[^3];
sub rotate($a is rw, $b is rw, Real \α) {
($a, $b) = cos(α)*$a + sin(α)*$b, -sin(α)*$a + cos(α)*$b;
}
rotate($i, $j, $longitude-of-ascending-node);
rotate($j, $k, $inclination);
rotate($i, $j, $argument-of-periapsis);
my \l = $eccentricity == 1 ?? # PARABOLIC CASE
2*$semimajor-axis !!
$semimajor-axis*(1 - $eccentricity**2);
my ($c, $s) = .cos, .sin given $true-anomaly;
my \r = l/(1 + $eccentricity*$c);
my \rprime = $s*r**2/l;
my $position = r*($c*$i + $s*$j);
my $speed =
(rprime*$c - r*$s)*$i + (rprime*$s + r*$c)*$j;
$speed /= sqrt($speed**2);
$speed *= sqrt(2/r - 1/$semimajor-axis);
{ :$position, :$speed }
}
say orbital-state-vectors
semimajor-axis => 1,
eccentricity => 0.1,
inclination => pi/18,
longitude-of-ascending-node => pi/6,
argument-of-periapsis => pi/4,
true-anomaly => 0;</lang>
{{out}}
<pre>{position => 0.237771283982207*e0+0.860960261697716*e1+0.110509023572076*e2, speed => -1.06193301748006*e0+0.27585002056925*e1+0.135747024865598*e2}</pre>
=={{header|REXX}}==
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