Fixed python calculations, added gitignore

Matlab/trap_forces_axial.m

@@ -0,0 +1,58 @@
+clear
+close all
+clc
+format compact
+
+% These calculations are based on Ashkin's article "Forces of a single-beam
+% gradient laser trap on a dielectric sphere in the ray optics regime".
+% There are axial forces only
+
+load_constants
+
+% Intensity profile plots
+rho = linspace(-r_max, r_max, 500);
+figure
+I = gauss(rho, w0, r_max);
+I0 = max(I);
+plot(rho, I/I0, 'k')
+grid
+xlabel('r, м')
+ylabel('I(r)')
+
+% Integration
+Qres_g = @(z) 2*pi / (pi * w0 ^ 2) * integral(@(r) r .* gauss(r, w0, r_max) .* ...
+    iscomplex(qg_z_factor(r, z, n1, n2, Rsp, f)), 0, r_max, ...
+    'AbsTol', 1e-12, 'RelTol', 1e-6);
+
+Qres_s = @(z) 2*pi / (pi * w0 ^ 2) * integral(@(r) r .* gauss(r, w0, r_max) .* ...
+    iscomplex(qs_z_factor(r, z, n1, n2, Rsp, f)), 0, r_max, ...
+    'AbsTol', 1e-12, 'RelTol', 1e-6);
+
+% Calulation
+N = 200;
+z = linspace(-2*Rsp, 2*Rsp, N);
+Axial_g = zeros(1, N);
+Axial_s = zeros(1, N);
+
+wb = waitbar(0, 'Calculating...');
+for ii = 1:N
+    Axial_g(ii) = Qres_g(z(ii));
+    Axial_s(ii) = Qres_s(z(ii));
+    waitbar(ii / N, wb, 'Calculating...');
+end
+close(wb);
+
+Axial_g = fliplr(Axial_g);
+Axial_s = fliplr(Axial_s);
+Axial = Axial_g + Axial_s;
+z = -fliplr(z);
+
+% Plots
+figure
+plot(z, F0 * Axial_g, 'b-.', ...
+    z, F0 * Axial_s, 'r--', ...
+    z, F0 * Axial, 'k')
+legend('F_{g}','F_{s}','F_{t}')
+xlabel('r, м')
+ylabel('F, Н')
+grid