Orbital elements: Difference between revisions
Added FreeBASIC
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<pre>Position : (0.7794228433986798, 0.4500000346536842, 0.0000000000000000)
Speed : (-0.5527708409604437, 0.9574270831797614, 0.0000000000000000)</pre>
=={{header|FreeBASIC}}==
{{trans|Phix}}
<syntaxhighlight lang="vbnet">Sub vabs(v() As Double, Byref result As Double)
For i As Integer = Lbound(v) To Ubound(v)
result += v(i) * v(i)
Next i
result = Sqr(result)
End Sub
Sub mulAdd(v1() As Double, x1 As Double, v2() As Double, x2 As Double, result() As Double)
For i As Integer = Lbound(v1) To Ubound(v1)
result(i) = v1(i) * x1 + v2(i) * x2
Next i
End Sub
Sub rotate(i() As Double, j() As Double, alfa As Double, result1() As Double, result2() As Double)
Dim As Double ca = Cos(alfa), sa = Sin(alfa)
mulAdd(i(), ca, j(), sa, result1())
mulAdd(i(), -sa, j(), ca, result2())
End Sub
Sub orbitalStateVectors(semimajorAxis As Double, eccentricity As Double, inclination As Double, longitudeOfAscendingNode As Double, argumentOfPeriapsis As Double, trueAnomaly As Double)
Dim As Double i(1 To 3) = {1, 0, 0}
Dim As Double j(1 To 3) = {0, 1, 0}
Dim As Double k(1 To 3) = {0, 0, 1}
Dim As Double temp1(1 To 3), temp2(1 To 3)
Dim As Integer index, t
rotate(i(), j(), longitudeOfAscendingNode, temp1(), temp2())
For index = 1 To 3
i(index) = temp1(index)
j(index) = temp2(index)
Next index
rotate(j(), k(), inclination, temp1(), temp2())
For index = 1 To 3
j(index) = temp1(index)
Next index
rotate(i(), j(), argumentOfPeriapsis, temp1(), temp2())
For index = 1 To 3
i(index) = temp1(index)
j(index) = temp2(index)
Next index
Dim As Double l = Iif(eccentricity = 1, 2, 1 - eccentricity * eccentricity) * semimajorAxis
Dim As Double c = Cos(trueAnomaly), s = Sin(trueAnomaly)
Dim As Double r = 1 / (1 + eccentricity * c)
Dim As Double rprime = s * r * r / l
Dim As Double posn(1 To 3), speed(1 To 3), vabsResult
mulAdd(i(), c, j(), s, posn())
For t = Lbound(posn) To Ubound(posn)
Next t
mulAdd(i(), rprime * c - r * s, j(), rprime * s + r * c, speed())
vabs(speed(), vabsResult)
mulAdd(speed(), 1 / vabsResult, speed(), 0, speed())
For t = Lbound(speed) To Ubound(speed)
speed(t) *= Sqr(2 / r - 1 / semimajorAxis)
Next t
Print Using "Position : {&, &, &}"; posn(1); posn(2); posn(3)
Print Using "Speed : {&, &, &}"; speed(1); speed(2); speed(3)
End Sub
orbitalStateVectors(1.0, 0.1, 0.0, 355.0 / (113.0 * 6.0), 0.0, 0.0)
Sleep</syntaxhighlight>
{{out}}
<pre>Position : {0.7872958014128079, 0.454545489549176, 0}
Speed : {-0.5477225996842874, 0.9486832736983857, 0}</pre>
=={{header|Go}}==
Line 2,103 ⟶ 2,174:
=={{header|Wren}}==
{{trans|Kotlin}}
{{libheader|Wren-vector}}
<syntaxhighlight lang="
▲ _x = x
▲ _y = y
▲ }
var orbitalStateVectors = Fn.new { |semimajorAxis, eccentricity, inclination,
longitudeOfAscendingNode, argumentOfPeriapsis, trueAnomaly|
var i =
var j =
var k =
var mulAdd = Fn.new { |v1, x1, v2, x2| v1 * x1 + v2 * x2 }
Line 2,154 ⟶ 2,206:
var position = mulAdd.call(i, c, j, s) * r
var speed = mulAdd.call(i, rprime * c - r * s, j, rprime * s + r * c)
speed = speed / speed.
speed = speed * (2 / r - 1 / semimajorAxis).sqrt
return [position, speed]
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