Theory stuff from sials work pc; minor stuff here and there
This commit is contained in:
Silas Oettinghaus
@@ -23,12 +23,16 @@ D_lin = S0 .* (lambda_nm - lambda0_nm);
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% plot
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figure('Color','w'); hold on;
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cols = cbrewer2('paired',4);
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plot(lambda_nm, D_lin(1,:), '-', 'LineWidth',2, 'DisplayName','Linearized model','Color',[cols(1,:)]);
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plot(lambda_nm, D_exact(1,:), 'LineWidth',2, 'DisplayName',sprintf('Exact model'),'Color',[cols(2,:)]);
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cols = [0.6510 0.8078 0.8902;...
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0.1216 0.4706 0.7059;...
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0.6980 0.8745 0.5412;...
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0.2000 0.6275 0.1725];
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plot(lambda_nm, D_lin(2,:), '-', 'LineWidth',2, 'HandleVisibility','off','Color',[cols(3,:)]);
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plot(lambda_nm, D_exact(2,:), 'LineWidth',2, 'HandleVisibility','off','Color',[cols(4,:)]);
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% plot(lambda_nm, D_lin(1,:), '-', 'LineWidth',2, 'DisplayName','Linearized model','Color',[cols(1,:)]);
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plot(lambda_nm, D_exact(1,:), 'LineWidth',2, 'DisplayName',sprintf('S_0 = 0.07'),'Color',[cols(2,:)]);
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% plot(lambda_nm, D_lin(2,:), '-', 'LineWidth',2, 'HandleVisibility','off','Color',[cols(3,:)]);
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plot(lambda_nm, D_exact(2,:), 'LineWidth',2, 'HandleVisibility','on', 'DisplayName',sprintf('S_0 = 0.09'),'Color',[cols(4,:)]);
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xlabel('Wavelength $\lambda$ [nm]','Interpreter','latex');
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@@ -36,4 +40,7 @@ ylabel('D($\lambda$) [ps/(nm km)]','Interpreter','latex');
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title('Chromatic Dispersion Around the ZDW');
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legend('Location','best');
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grid on; box on;
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xlim([min(lambda_nm) max(lambda_nm)])
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ylim([-5 5]);
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% mat2tikz_improved('C:\Users\Silas\Documents\6971e0b65b380ca6d71c837f\02_IMDD_System\tikz\dispersion\dispersion')
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124
Functions/Theory/Dissertation/photo_diode.m
Normal file
124
Functions/Theory/Dissertation/photo_diode.m
Normal file
@@ -0,0 +1,124 @@
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%% ============================================================
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% SNR vs Optical Input Power (dBm) — Shot vs Thermal vs Combined
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% - Generate optical field as sine with target RMS power (verified)
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% - Magnitude-square detection -> optical power
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% - Photocurrent = Rd * P
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% - Add shot noise + thermal noise (white, PSD-based)
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% - Compute SNR for: shot-only, thermal-only, combined
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% ============================================================
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% Constants
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k = Constant.Boltzmann;
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q = Constant.ElementaryCharge;
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% Receiver / PD parameters
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T = 20 + 273.15; % K
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R = 50; % Ohm (front-end/load)
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Rd = 0.7; % A/W (responsivity)
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Be = 100e9; % Hz (electrical noise bandwidth)
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Id = 0; % A (dark current, optional)
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% Sampling for time-domain demo (needs to be >> Be)
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fs = 1e12; % Hz
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N = 2^14; % samples
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t = (0:N-1).'/fs;
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% Choose an electrical tone within bandwidth (arbitrary for demo)
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f0 = 10e9; % Hz
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% Thermal current PSD (two-sided) and variance in Be
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Si_th = 4*k*T/R; % A^2/Hz (two-sided)
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sigma2_th = Si_th * Be; % A^2
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sigma_th = sqrt(sigma2_th); % A_rms
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% Optical input power sweep (in dBm)
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P_dBm = linspace(-40, 10, 300);
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P_W = 10.^((P_dBm - 30)/10); % W
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% Pre-allocate results
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SNR_shot_dB = zeros(size(P_dBm));
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SNR_th_dB = zeros(size(P_dBm));
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SNR_tot_dB = zeros(size(P_dBm));
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% --- Main loop over optical input power
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for ii = 1:numel(P_W)
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Pavg = P_W(ii);
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% Optical field with RMS power = Pavg:
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% Let x(t) be the optical field amplitude such that |x|^2 has mean Pavg.
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% Use a sinusoid: x(t) = A*sin(2*pi*f0*t), then mean(|x|^2)=A^2/2.
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A = sqrt(2*Pavg); % -> mean(|x|^2) = Pavg
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x = A * sin(2*pi*f0*t); % "optical field" (real for simplicity)
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% Verify RMS/mean power numerically (optional)
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P_meas = mean(abs(x).^2); % should be ~ Pavg
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a = P_meas - Pavg;
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assert(a<1);
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% Magnitude-square detection -> optical power waveform
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Popt = abs(x).^2; % W (instantaneous)
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% Photocurrent waveform (includes DC + 2f0 component for this demo)
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I_sig = Rd * Popt; % A
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% Define "signal power" as the mean-squared photocurrent due to signal
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% (for this sine-squared waveform, it's OK for a demo SNR definition)
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P_sig = mean(I_sig.^2);
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% -------- Shot noise (white) --------
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% Two-sided PSD: Si_shot = 2*q*(I_photo + I_dark)
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% For this demo, use average current to set the white-noise level:
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Ibar = mean(I_sig) + Id;
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Si_shot = 2*q*Ibar; % A^2/Hz
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sigma2_sh = Si_shot * Be; % A^2
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sigma_sh = sqrt(sigma2_sh); % A_rms
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n_sh = sigma_sh * randn(N,1); % time-domain shot noise
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% -------- Thermal noise (white Gaussian) --------
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n_th = sigma_th * randn(N,1); % time-domain thermal noise
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% Noise powers (mean-square) in time domain
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Pn_sh = mean(n_sh.^2);
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Pn_th = mean(n_th.^2);
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Pn_tot = mean((n_sh + n_th).^2); % ~ Pn_sh + Pn_th (independent)
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% SNRs
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SNR_shot = P_sig / Pn_sh;
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SNR_th = P_sig / Pn_th;
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SNR_tot = P_sig / Pn_tot;
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SNR_shot_dB(ii) = 10*log10(SNR_shot);
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SNR_th_dB(ii) = 10*log10(SNR_th);
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SNR_tot_dB(ii) = 10*log10(SNR_tot);
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% Optional sanity check (can comment out)
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% if ii == 1
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% fprintf('Check Pavg target/meas: %.3g W / %.3g W\n', Pavg, P_meas);
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% end
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end
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% Plot comparison
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figure(1); clf; hold on;
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plot(P_dBm, SNR_shot_dB, 'LineWidth', 1.5);
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plot(P_dBm, SNR_th_dB, 'LineWidth', 1.5);
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plot(P_dBm, SNR_tot_dB, 'LineWidth', 1.5);
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grid on;
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xlabel('Optical input power [dBm]');
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ylabel('SNR [dB]');
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title('SNR vs Optical Input Power: Shot vs Thermal vs Combined');
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legend('Shot-noise only','Thermal-noise only','Shot + Thermal','Location','best');
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% Print example at 0 dBm
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[~,idx0] = min(abs(P_dBm - 0));
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fprintf('At 0 dBm:\n');
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fprintf(' SNR (shot only) = %.2f dB\n', SNR_shot_dB(idx0));
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fprintf(' SNR (thermal only) = %.2f dB\n', SNR_th_dB(idx0));
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fprintf(' SNR (combined) = %.2f dB\n', SNR_tot_dB(idx0));
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% Also print NEP based on thermal PSD (constant NEP_th)
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NEP_th = sqrt(Si_th)/Rd; % W/sqrt(Hz)
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fprintf('Thermal NEP = %.3g W/sqrt(Hz)\n', NEP_th);
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68
Functions/Theory/Dissertation/power_fading_gif.m
Normal file
68
Functions/Theory/Dissertation/power_fading_gif.m
Normal file
@@ -0,0 +1,68 @@
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%% ============================================================
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% IM/DD Power Fading Evolution GIF (1 km -> 20 km)
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% Uses the provided GifWriter (serial mode)
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% ============================================================
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clear; close all; clc;
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%% Fiber and system parameters
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lambda0 = 1310e-9; % zero-dispersion wavelength [m]
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lambda = 1275e-9; % operating wavelength [m]
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S0 = 0.09; % dispersion slope [ps/(nm^2·km)]
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c = physconst('lightspeed');
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%% Derived quantities (length-independent)
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D_lambda = (S0/4) * (lambda*1e9 - (lambda0*1e9)^4/(lambda*1e9)^3); % ps/(nm·km)
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D_si = D_lambda * 1e-6; % s/m^2
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b2 = -D_si * lambda^2 / (2*pi*c); % s^2/m
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%% Frequency grid
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f_max = 150e9;
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f = linspace(0, f_max, 4000); % [Hz]
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%% Figure setup (keep it stable for nicer GIFs)
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fig = figure('Color','w');
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ax = axes(fig); %#ok<LAXES>
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hold(ax,'on'); grid(ax,'on'); box(ax,'on');
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xlabel(ax,'Frequency [GHz]');
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ylabel(ax,'Magnitude [dB]');
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ylim(ax,[-30 0]);
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xlim(ax,[0 f_max/1e9]);
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%% GIF writer (serial mode; simplest)
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g = GifWriter('Name','power_fading_evolution', 'DelayTime',0.12, 'Parallel',false);
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%% Loop: 1 km to 20 km
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L = [1:20,19:-1:1];
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for L_km = L
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L_meter = L_km * 1e3; % [m]
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% IM/DD transfer function (power fading)
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phi = 2*pi^2 * b2 * f.^2 * L_meter;
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H = abs(cos(phi));
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HdB = 10*log10(max(H, 1e-12)); % avoid -Inf for deep notches
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% Clear and redraw (stable axes)
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cla(ax);
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plot(ax, f/1e9, HdB, 'LineWidth', 1.8, 'Color','black');
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% Analytic first-null frequency marker
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f_null = sqrt(c*(0.5)/(abs(D_si)*lambda^2*L_meter));
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xline(ax, f_null/1e9, 'r--', 'LineWidth', 1.2, ...
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'Label', sprintf('f_{null}=%.1f GHz', f_null/1e9), ...
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'LabelOrientation','horizontal', ...
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'LabelVerticalAlignment','bottom');
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title(ax, sprintf('Power Fading for: %.0f km @ 1275 nm', L_km));
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drawnow;
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% Add frame to GIF
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g.addFrame(fig);
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end
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%% Done
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g.compile(fig.Number);
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disp(fullfile(g.OutputDir, sprintf('%s_fig_%d.gif', g.Name, fig.Number)));
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@@ -0,0 +1,69 @@
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%% ============================================================
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% IM/DD Power Fading Evolution vs Wavelength (L = 10 km)
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% ============================================================
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clear; close all; clc;
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%% Fixed fiber parameters
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lambda0 = 1310e-9; % zero-dispersion wavelength [m]
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S0 = 0.09; % dispersion slope [ps/(nm^2·km)]
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L = 10e3; % fiber length FIXED [m]
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c = physconst('lightspeed');
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%% Frequency grid
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f_max = 150e9;
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f = linspace(0, f_max, 4000); % [Hz]
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%% Figure setup (stable axes for clean GIF)
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fig = figure('Color','w');
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ax = axes(fig);
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hold(ax,'on'); grid(ax,'on'); box(ax,'on');
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xlabel(ax,'Frequency [GHz]');
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ylabel(ax,'Magnitude [dB]');
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ylim(ax,[-30 0]);
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xlim(ax,[0 f_max/1e9]);
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%% GIF writer
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g = GifWriter('Name','power_fading_vs_wavelength', ...
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'DelayTime',0.12, ...
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'Parallel',false);
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%% Wavelength sweep (around ZDW)
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lambda_vec = linspace(1260e-9, 1360e-9, 25); % 1260–1360 nm
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for k = 1:length(lambda_vec)
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lambda = lambda_vec(k);
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%% Dispersion for current wavelength
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D_lambda = (S0/4) * (lambda*1e9 - (lambda0*1e9)^4/(lambda*1e9)^3); % ps/(nm·km)
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D_si = D_lambda * 1e-6; % s/m^2
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b2 = -D_si * lambda^2 / (2*pi*c); % s^2/m
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%% Power fading transfer function
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phi = 2*pi^2 * b2 * f.^2 * L;
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H = abs(cos(phi));
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HdB = 10*log10(max(H, 1e-12));
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cla(ax)
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plot(ax, f/1e9, HdB, 'LineWidth',1.8,'Color','black');
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%% First-null frequency
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if abs(D_si) > 0
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f_null = sqrt(c*(0.5)/(abs(D_si)*lambda^2*L));
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xline(ax, f_null/1e9, 'r--', 'LineWidth',1.2, ...
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'Label', sprintf('f_{null}=%.1f GHz', f_null/1e9), ...
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'LabelOrientation','horizontal', ...
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'LabelVerticalAlignment','bottom');
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end
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title(ax, sprintf('Power Fading for: 10 km @ %.0f nm', lambda*1e9));
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drawnow;
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g.addFrame(fig);
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end
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%% Compile GIF
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g.compile(fig.Number);
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disp(fullfile(g.OutputDir, sprintf('%s_fig_%d.gif', g.Name, fig.Number)));
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@@ -8,17 +8,16 @@ c = physconst('lightspeed');
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S0_si = S0 * 1e3; % s/m³
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Delta_lambda = linspace(5e-9, 80e-9, 300); % [m] detuning
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f_null_2 = sqrt( c * 0.5 ./ (S0_si .* abs(Delta_lambda) .* lambda0.^2 .* L) );
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L = 2e3; % m
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f_null_10 = sqrt( c * 0.5 ./ (S0_si .* abs(Delta_lambda) .* lambda0.^2 .* L) );
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cols = cbrewer2('Paired',10);
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cols = [0.3467 0.5360 0.6907;...
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0.9153 0.2816 0.2878;...
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0.4416 0.7490 0.4322];
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figure('Color','w');hold on
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cnt = 2;
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for L = 10%[2,5,10]
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cnt = 1;
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for L = [2,10,40]
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f_null_10 = sqrt( c * 0.5 ./ (S0_si .* abs(Delta_lambda) .* lambda0.^2 .* L*1e3) );
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plot(1310-Delta_lambda*1e9, f_null_10/1e9, 'LineWidth',2,'DisplayName',sprintf('%d km',L),'Color',cols(cnt,:));
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cnt = cnt+2;
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cnt = cnt+1;
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end
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% yticks([56,75,90,112])
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% tickse = 1310-[7.5, 12, 17, 31.5];
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@@ -29,4 +28,5 @@ ylabel('$F_{null}$ [GHz]');
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grid on; box on;
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lim=1310-[5,60];
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xlim([lim(2) lim(1)]);
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ylim([40,130])
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ylim([10,130])
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legend
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@@ -5,7 +5,7 @@
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%% Fiber and system parameters
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lambda0 = 1310e-9; % zero-dispersion wavelength [m]
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lambda = 1275e-9; % operating wavelength [m]
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lambda = 1290e-9; % operating wavelength [m]
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S0 = 0.09; % dispersion slope [ps/(nm²·km)]
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L = 10e3; % fiber length [m]
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c = physconst('lightspeed');
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@@ -30,7 +30,7 @@ plot(f/1e9, 10*log10(H), 'LineWidth', 1.8,'Color','black');
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grid on; box on;
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xlabel('Frequency [GHz]');
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ylabel('Magnitude [dB]');
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title(sprintf('IM/DD Power Fading: 10 km; 1275nm', lambda*1e9, L/1000),"Interpreter","latex");
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% title(sprintf('IM/DD Power Fading: 10 km; 1275nm', lambda*1e9, L/1000),"Interpreter","latex");
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ylim([-30 0]);
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%% Mark analytic first-null frequency
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@@ -38,3 +38,5 @@ f_null = sqrt(c*(0.5)/(abs(D_si)*lambda^2*L));
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xline(f_null/1e9, 'r--', 'LineWidth', 1.2, ...
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'Label', sprintf('f_{null}=%.1f GHz', f_null/1e9), ...
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'LabelOrientation', 'horizontal', 'LabelVerticalAlignment', 'bottom');
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mat2tikz_improved('C:\Users\Silas\Documents\6971e0b65b380ca6d71c837f\02_IMDD_System\tikz\dispersion\power_fading.tikz')
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317
Functions/plot_s_parameter.m
Normal file
317
Functions/plot_s_parameter.m
Normal file
@@ -0,0 +1,317 @@
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%% Plot S-parameters from Touchstone S2P or S4P (schema-aware, no RF Toolbox)
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clear; clc;
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[file,path] = uigetfile({"*.s2p;*.S2P;*.s4p;*.S4P","Touchstone (*.s2p, *.s4p)"});
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if isequal(file,0); return; end
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filename = fullfile(path,file);
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%%
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% Decide port count by extension (minimal-invasive, robust)
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[~,~,ext] = fileparts(file);
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ext = upper(ext);
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if strcmp(ext,'.S4P')
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[matrix, meta] = loads4p_schema(filename);
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N = 4;
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elseif strcmp(ext,'.S2P')
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[matrix, meta] = loads2p(filename); % your original loader kept (below)
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N = 2;
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else
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error("Unsupported extension: %s", ext);
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end
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% Frequency in GHz
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frex = matrix(:,1);
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if isfield(meta,'freqScaleHz') && ~isempty(meta.freqScaleHz)
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frex = frex * meta.freqScaleHz / 1e9; % convert to GHz
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else
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% fallback heuristic (your original)
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for i = 1:numel(frex)
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if frex(i) > 1e4
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frex(i) = frex(i).*1e-9;
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end
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end
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end
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figure(101);
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hold on;
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% overlay indexing: count lines already there
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if N == 2
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lines = numel(findall(gcf, 'type','line'))/4 + 1;
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else
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lines = numel(findall(gcf, 'type','line'))/16 + 1;
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end
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% styles (kept)
|
||||
[CC, LL, MM] = ndgrid({1,2,3,4}, {'-', ':', '-.', '--'}, {'none','+', 'o', '*', 'square', 'diamond'});
|
||||
combinations = [CC(:), LL(:), MM(:)];
|
||||
cols = [0.3467 0.5360 0.6907
|
||||
0.9153 0.2816 0.2878
|
||||
0.4416 0.7490 0.4322
|
||||
1.0000 0.5984 0.2000];
|
||||
|
||||
% -------------------- Plotting --------------------
|
||||
if N == 2
|
||||
heads = ["S11","S12","S22","S21"];
|
||||
% matrix layout from loads2p:
|
||||
% col pairs:
|
||||
% 2-3 S11, 4-5 S21, 6-7 S12, 8-9 S22
|
||||
colPairs = [2 3; 6 7; 8 9; 4 5]; % order matches heads above
|
||||
subplots = 1;
|
||||
|
||||
for k = 1:4
|
||||
if subplots, subplot(2,2,k); else, figure('Color','w'); end
|
||||
hold on; grid on;
|
||||
|
||||
reCol = colPairs(k,1);
|
||||
imCol = colPairs(k,2);
|
||||
|
||||
% S-parameter magnitude in dB: 20*log10(|S|)
|
||||
response = 20*log10(abs(matrix(:,reCol) + 1i.*matrix(:,imCol)));
|
||||
response = movmean(response,1);
|
||||
|
||||
plot(frex, response, ...
|
||||
"Color", cols(combinations{lines,1},:), ...
|
||||
"DisplayName", file, ...
|
||||
"LineStyle", combinations{lines,2}, ...
|
||||
"Marker", combinations{lines,3}, ...
|
||||
"MarkerSize", 3);
|
||||
|
||||
if k == 2 || k == 3
|
||||
ylim([-6 2]);
|
||||
else
|
||||
ylim([-30 2]);
|
||||
end
|
||||
xlim([0 100]);
|
||||
title(heads(k));
|
||||
xlabel('Frequency in GHz');
|
||||
ylabel('|S| (dB)');
|
||||
legend('Location','best');
|
||||
end
|
||||
sgtitle(sprintf('S-Parameters (2-port) [%s]', meta.headerLine));
|
||||
|
||||
elseif N == 4
|
||||
% For s4p schema we plot all Sij in a 4x4 grid
|
||||
% matrix layout from loads4p_schema:
|
||||
% columns: 1=f, then pairs in order:
|
||||
% S11,S12,S13,S14, S21..S24, S31..S34, S41..S44
|
||||
subplots = 1;
|
||||
|
||||
for i = 1:4
|
||||
for j = 1:4
|
||||
sp = (i-1)*4 + j;
|
||||
if subplots, subplot(4,4,sp); else, figure('Color','w'); end
|
||||
hold on; grid on;
|
||||
|
||||
idx = (i-1)*4 + j; % 1..16 for Sij in row-major
|
||||
reCol = 1 + 2*(idx-1) + 1; % after freq col
|
||||
imCol = 1 + 2*(idx-1) + 2;
|
||||
|
||||
response = 20*log10(abs(matrix(:,reCol) + 1i.*matrix(:,imCol)));
|
||||
plot(frex, response, ...
|
||||
"Color", cols(combinations{lines,1},:), ...
|
||||
"DisplayName", file, ...
|
||||
"LineStyle", combinations{lines,2}, ...
|
||||
"Marker", combinations{lines,3}, ...
|
||||
"MarkerSize", 2);
|
||||
|
||||
xlim([0 100]);
|
||||
title(sprintf("S%d%d", i, j));
|
||||
set(gca,'FontSize',8);
|
||||
|
||||
% reduce clutter
|
||||
if j ~= 1, yticklabels([]); end
|
||||
if i ~= 4, xticklabels([]); end
|
||||
if j == 1, ylabel('|S| (dB)'); end
|
||||
if i == 4, xlabel('GHz'); end
|
||||
end
|
||||
end
|
||||
sgtitle(sprintf('S-Parameters (4-port) [%s]', meta.headerLine));
|
||||
end
|
||||
|
||||
|
||||
%% ========================================================================
|
||||
% Loader for S4P with the EXACT provided schema (4 lines per frequency)
|
||||
% ========================================================================
|
||||
function [matrix, meta] = loads4p_schema(filepath)
|
||||
meta = struct();
|
||||
meta.headerLine = "";
|
||||
meta.freqScaleHz = []; % Hz per file unit (e.g., GHz -> 1e9)
|
||||
|
||||
fid = fopen(filepath,'r');
|
||||
if fid < 0, error("Cannot open file: %s", filepath); end
|
||||
cleaner = onCleanup(@() fclose(fid));
|
||||
|
||||
% Parse header: find "#"
|
||||
freUnit = "";
|
||||
while true
|
||||
t = fgetl(fid);
|
||||
if ~ischar(t), break; end
|
||||
ts = strtrim(t);
|
||||
if startsWith(ts,'#')
|
||||
meta.headerLine = ts;
|
||||
parts = split(upper(string(ts)));
|
||||
if numel(parts) >= 2, freUnit = parts(2); end
|
||||
|
||||
switch freUnit
|
||||
case "HZ", meta.freqScaleHz = 1;
|
||||
case "KHZ", meta.freqScaleHz = 1e3;
|
||||
case "MHZ", meta.freqScaleHz = 1e6;
|
||||
case "GHZ", meta.freqScaleHz = 1e9;
|
||||
otherwise, meta.freqScaleHz = [];
|
||||
end
|
||||
break;
|
||||
end
|
||||
end
|
||||
|
||||
data = [];
|
||||
|
||||
while true
|
||||
l1 = nextNumericLine(fid);
|
||||
if strlength(l1) == 0
|
||||
break;
|
||||
end
|
||||
|
||||
% IMPORTANT: sscanf wants char for robust behavior
|
||||
v1 = sscanf(char(l1), '%f').';
|
||||
if numel(v1) < 9
|
||||
error("S4P schema mismatch: expected 9 numbers on first line of a block, got %d.\nLine: %s", numel(v1), char(l1));
|
||||
end
|
||||
|
||||
l2 = nextNumericLine(fid); if strlength(l2)==0, error("Unexpected EOF after first S4P line."); end
|
||||
l3 = nextNumericLine(fid); if strlength(l3)==0, error("Unexpected EOF after second S4P line."); end
|
||||
l4 = nextNumericLine(fid); if strlength(l4)==0, error("Unexpected EOF after third S4P line."); end
|
||||
|
||||
v2 = sscanf(char(l2), '%f').';
|
||||
v3 = sscanf(char(l3), '%f').';
|
||||
v4 = sscanf(char(l4), '%f').';
|
||||
|
||||
if numel(v2) < 8 || numel(v3) < 8 || numel(v4) < 8
|
||||
error("S4P schema mismatch: expected 8 numbers on continuation lines.\nL2: %s\nL3: %s\nL4: %s", char(l2), char(l3), char(l4));
|
||||
end
|
||||
|
||||
f = v1(1);
|
||||
s1 = v1(2:9); % S11..S14 (re/im pairs)
|
||||
s2 = v2(1:8); % S21..S24
|
||||
s3 = v3(1:8); % S31..S34
|
||||
s4 = v4(1:8); % S41..S44
|
||||
|
||||
row = [f, s1, s2, s3, s4]; % 1 + 32 = 33 columns
|
||||
data = [data; row]; %#ok<AGROW>
|
||||
end
|
||||
|
||||
matrix = data;
|
||||
end
|
||||
|
||||
|
||||
function ln = nextNumericLine(fid)
|
||||
ln = "";
|
||||
|
||||
while true
|
||||
t = fgetl(fid);
|
||||
if ~ischar(t)
|
||||
ln = "";
|
||||
return;
|
||||
end
|
||||
|
||||
ts = strtrim(t);
|
||||
|
||||
% Skip blanks and comments and header lines
|
||||
if ts=="" || startsWith(ts,'!') || startsWith(ts,'#')
|
||||
continue;
|
||||
end
|
||||
|
||||
% Remove inline comment after '!' if present
|
||||
excl = strfind(ts,'!');
|
||||
if ~isempty(excl)
|
||||
ts = strtrim(extractBefore(ts, excl(1)));
|
||||
if ts==""; continue; end
|
||||
end
|
||||
|
||||
% Keep only if there's at least one numeric token
|
||||
if ~isempty(regexp(ts,'[-+]?\d*\.?\d+(?:[eEdD][-+]?\d+)?','once'))
|
||||
ln = string(ts);
|
||||
return;
|
||||
end
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
|
||||
%% ========================================================================
|
||||
% Your original loads2p (kept as-is, but returns meta too)
|
||||
% ========================================================================
|
||||
function [matrix, meta] = loads2p(filepath)
|
||||
meta = struct();
|
||||
meta.headerLine = "";
|
||||
meta.freqScaleHz = [];
|
||||
|
||||
% Try to read # line for unit scaling (minimal invasive)
|
||||
fid = fopen(filepath,'r');
|
||||
if fid >= 0
|
||||
cleaner = onCleanup(@() fclose(fid));
|
||||
while true
|
||||
t = fgetl(fid);
|
||||
if ~ischar(t), break; end
|
||||
ts = strtrim(t);
|
||||
if startsWith(ts,'#')
|
||||
meta.headerLine = ts;
|
||||
parts = split(upper(string(ts)));
|
||||
if numel(parts) >= 2
|
||||
switch parts(2)
|
||||
case "HZ", meta.freqScaleHz = 1;
|
||||
case "KHZ", meta.freqScaleHz = 1e3;
|
||||
case "MHZ", meta.freqScaleHz = 1e6;
|
||||
case "GHZ", meta.freqScaleHz = 1e9;
|
||||
end
|
||||
end
|
||||
break;
|
||||
end
|
||||
end
|
||||
end
|
||||
|
||||
startRow = 2;
|
||||
formatSpec = '%20s%25s%23s%23s%23s%23s%23s%23s%23s%s%[^\n\r]';
|
||||
|
||||
fileID = fopen(filepath,'r');
|
||||
dataArray = textscan(fileID, formatSpec, 'Delimiter', '', 'WhiteSpace', '', ...
|
||||
'TextType', 'string', 'HeaderLines' ,startRow-1, 'ReturnOnError', false, 'EndOfLine', '\r\n');
|
||||
fclose(fileID);
|
||||
|
||||
raw = repmat({''},length(dataArray{1}),length(dataArray)-1);
|
||||
for col=1:length(dataArray)-1
|
||||
raw(1:length(dataArray{col}),col) = mat2cell(dataArray{col}, ones(length(dataArray{col}), 1));
|
||||
end
|
||||
numericData = NaN(size(dataArray{1},1),size(dataArray,2));
|
||||
|
||||
for col=[1,2,3,4,5,6,7,8,9,10]
|
||||
rawData = dataArray{col};
|
||||
for row=1:size(rawData, 1)
|
||||
regexstr = '(?<prefix>.*?)(?<numbers>([-]*(\d+[\,]*)+[\.]{0,1}\d*[eEdD]{0,1}[-+]*\d*[i]{0,1})|([-]*(\d+[\,]*)*[\.]{1,1}\d+[eEdD]{0,1}[-+]*\d*[i]{0,1}))(?<suffix>.*)';
|
||||
try
|
||||
result = regexp(rawData(row), regexstr, 'names');
|
||||
numbers = result.numbers;
|
||||
|
||||
invalidThousandsSeparator = false;
|
||||
if numbers.contains(',')
|
||||
thousandsRegExp = '^[-/+]*\d+?(\,\d{3})*\.{0,1}\d*$';
|
||||
if isempty(regexp(numbers, thousandsRegExp, 'once'))
|
||||
numbers = NaN;
|
||||
invalidThousandsSeparator = true;
|
||||
end
|
||||
end
|
||||
if ~invalidThousandsSeparator
|
||||
numbers = textscan(char(strrep(numbers, ',', '')), '%f');
|
||||
numericData(row, col) = numbers{1};
|
||||
raw{row, col} = numbers{1};
|
||||
end
|
||||
catch
|
||||
raw{row, col} = rawData{row};
|
||||
end
|
||||
end
|
||||
end
|
||||
|
||||
R = cellfun(@(x) ~isnumeric(x) && ~islogical(x),raw);
|
||||
raw(R) = {NaN};
|
||||
|
||||
matrix = cell2mat(raw);
|
||||
end
|
||||
Reference in New Issue
Block a user