[03cac08] | 1 | #define INVALID(v) (v.radius<0 || v.length<0) |
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| 2 | |
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[2a0b2b1] | 3 | static double |
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| 4 | form_volume(double radius, double length) |
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[14de349] | 5 | { |
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| 6 | return M_PI*radius*radius*length; |
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| 7 | } |
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| 8 | |
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[2a0b2b1] | 9 | static double |
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| 10 | fq(double qab, double qc, double radius, double length) |
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[14de349] | 11 | { |
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[2a0b2b1] | 12 | return sas_2J1x_x(qab*radius) * sas_sinx_x(qc*0.5*length); |
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[0d6e865] | 13 | } |
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[50e1e40] | 14 | |
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[2a0b2b1] | 15 | static double |
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| 16 | orient_avg_1D(double q, double radius, double length) |
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[0d6e865] | 17 | { |
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[50e1e40] | 18 | // translate a point in [-1,1] to a point in [0, pi/2] |
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| 19 | const double zm = M_PI_4; |
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[2a0b2b1] | 20 | const double zb = M_PI_4; |
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[50e1e40] | 21 | |
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[994d77f] | 22 | double total = 0.0; |
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[74768cb] | 23 | for (int i=0; i<GAUSS_N ;i++) { |
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| 24 | const double theta = GAUSS_Z[i]*zm + zb; |
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[2a0b2b1] | 25 | double sin_theta, cos_theta; // slots to hold sincos function output |
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| 26 | // theta (theta,phi) the projection of the cylinder on the detector plane |
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| 27 | SINCOS(theta , sin_theta, cos_theta); |
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| 28 | const double form = fq(q*sin_theta, q*cos_theta, radius, length); |
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[74768cb] | 29 | total += GAUSS_W[i] * form * form * sin_theta; |
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[14de349] | 30 | } |
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[ff7119b] | 31 | // translate dx in [-1,1] to dx in [lower,upper] |
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[0d6e865] | 32 | return total*zm; |
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| 33 | } |
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| 34 | |
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[2a0b2b1] | 35 | static double |
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| 36 | Iq(double q, |
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[0d6e865] | 37 | double sld, |
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| 38 | double solvent_sld, |
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| 39 | double radius, |
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| 40 | double length) |
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| 41 | { |
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[50e1e40] | 42 | const double s = (sld - solvent_sld) * form_volume(radius, length); |
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[0d6e865] | 43 | return 1.0e-4 * s * s * orient_avg_1D(q, radius, length); |
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[14de349] | 44 | } |
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| 45 | |
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[2a0b2b1] | 46 | static double |
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[108e70e] | 47 | Iqac(double qab, double qc, |
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[994d77f] | 48 | double sld, |
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| 49 | double solvent_sld, |
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| 50 | double radius, |
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[becded3] | 51 | double length) |
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[14de349] | 52 | { |
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[50e1e40] | 53 | const double s = (sld-solvent_sld) * form_volume(radius, length); |
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[2a0b2b1] | 54 | const double form = fq(qab, qc, radius, length); |
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[73e08ae] | 55 | return 1.0e-4 * square(s * form); |
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[14de349] | 56 | } |
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