20 lines
924 B
JavaScript
20 lines
924 B
JavaScript
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var besselk/*:BesselF*/ = (function() {
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var b0_a = [-0.57721566, 0.42278420, 0.23069756, 0.3488590e-1, 0.262698e-2, 0.10750e-3, 0.74e-5].reverse();
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var b0_b = [1.25331414, -0.7832358e-1, 0.2189568e-1, -0.1062446e-1, 0.587872e-2, -0.251540e-2, 0.53208e-3].reverse();
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function bessel0(x/*:number*/)/*:number*/ {
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if(x <= 2) return -M.log(x/2) * besseli(x,0) + _horner(b0_a, x*x/4);
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return M.exp(-x) / M.sqrt(x) * _horner(b0_b, 2/x);
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}
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var b1_a = [1.0, 0.15443144, -0.67278579, -0.18156897, -0.1919402e-1, -0.110404e-2, -0.4686e-4].reverse();
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var b1_b = [1.25331414, 0.23498619, -0.3655620e-1, 0.1504268e-1, -0.780353e-2, 0.325614e-2, -0.68245e-3].reverse();
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function bessel1(x/*:number*/)/*:number*/ {
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if(x <= 2) return M.log(x/2) * besseli(x,1) + (1/x) * _horner(b1_a, x*x/4);
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return M.exp(-x)/M.sqrt(x)*_horner(b1_b, 2/x);
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}
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return _bessel_wrap(bessel0, bessel1, 'BESSELK', 2, 1);
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})();
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