38 lines
824 B
JavaScript
38 lines
824 B
JavaScript
function fact(n)
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{
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if (n <= 1)
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return 1
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for (var i = n - 1; i >= 1; i--)
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n *= i;
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return n
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}
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function assoc_legendre(l, m, x)
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{
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l = Math.floor(l);
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m = Math.floor(m);
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if (x > 1 || x < -1 || l < 0 || m > l)
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return 0;
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if (m === l)
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return (Math.pow(-1, m) * fact(2*m) / (Math.pow(2, m) * fact(m)) * Math.pow(1 - x*x, m/2))
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return (x * (2*l - 1) * assoc_legendre(l-1, m, x) - (l + m - 1) * assoc_legendre(l-2, m, x)) / (l - m)
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}
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function N(l, m)
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{
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return Math.sqrt((2*l + 1)/2 * fact(l-m) / fact(l+m));
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}
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function Y(l, m, theta, phi)
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{
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var a = 1 / Math.sqrt(2 * Math.PI) * N(l, Math.abs(m)) * assoc_legendre(l, Math.abs(m), Math.cos(theta))
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if(m >= 0)
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return a * Math.cos(m * phi)
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else
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return a * Math.sin(Math.abs(m) * phi)
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} |