39 lines
906 B
Text
39 lines
906 B
Text
func thiele(x, y) {
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var ρ = {|i| [y[i]]*(y.len-i) }.map(^y)
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for i in ^(ρ.end) {
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ρ[i][1] = ((x[i] - x[i+1]) / (ρ[i][0] - ρ[i+1][0]))
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}
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for i (2 .. ρ.end) {
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for j (0 .. ρ.end-i) {
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ρ[j][i] = (((x[j]-x[j+i]) / (ρ[j][i-1]-ρ[j+1][i-1])) + ρ[j+1][i-2])
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}
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}
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var ρ0 = ρ[0]
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func t(xin) {
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var a = 0
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for i (ρ0.len ^.. 2) {
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a = ((xin - x[i-1]) / (ρ0[i] - ρ0[i-2] + a))
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}
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y[0] + ((xin-x[0]) / (ρ0[1]+a))
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}
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return t
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}
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# task 1: build 32 row trig table
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var xVal = {|k| k * 0.05 }.map(^32)
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var tSin = xVal.map { .sin }
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var tCos = xVal.map { .cos }
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var tTan = xVal.map { .tan }
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# task 2: define inverses
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var iSin = thiele(tSin, xVal)
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var iCos = thiele(tCos, xVal)
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var iTan = thiele(tTan, xVal)
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# task 3: demonstrate identities
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say 6*iSin(0.5)
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say 3*iCos(0.5)
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say 4*iTan(1)
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