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Why is the python matlab.engine 2-3 times slower when running on another equally powerful cpu?

/ 2024-09-26

I am using the matlab engine to convert stimulation patterns of cochlear implants into audio through a vocoder supplied by cochlear ltd from my python code.
My code is quite fast when I run it on my computer, the part that uses the matlab engine runs in about 2 seconds if I use 10 engines in parallel.
Now I tried to run my code in our cluster on a machine with epyc cpus, which are at least as fast as my own computer’s cpu. However, while the rest of my code runs on this cluster computer almost as fast as on my own machine – I see at most an increase by a factor of 1.2 – the matlab.engine part is slowed down by a factor of 2-3, i.e., the same code requires 8-9 seconds instead of 2-3 seconds, which is quite detrimental in a large scale experiment.
The slice of code that uses the matlab.engine, and which slows down on the other machine, is
for i, pred in enumerate(predictions):
original_length = dataset[i][‘length_EP’]
pred = ApplyPostProcessing(pred,original_length)
vocoded_futures[i] = eng_list[i%len(eng_list)].runVocoderPython(matlab.double(pred), nargout=2, background=True)
The "eng_list" variable is just a list of separate matlab engines I use to speed up the processing. "runVocoderPython" is just a wrapper for a matlab function that runs the vocoder.
Does anyone know what could cause this specific slowdown of the matlab.engine?
I use Python 3.8.19, Matlab 2022a and Linux as OS.I am using the matlab engine to convert stimulation patterns of cochlear implants into audio through a vocoder supplied by cochlear ltd from my python code.
My code is quite fast when I run it on my computer, the part that uses the matlab engine runs in about 2 seconds if I use 10 engines in parallel.
Now I tried to run my code in our cluster on a machine with epyc cpus, which are at least as fast as my own computer’s cpu. However, while the rest of my code runs on this cluster computer almost as fast as on my own machine – I see at most an increase by a factor of 1.2 – the matlab.engine part is slowed down by a factor of 2-3, i.e., the same code requires 8-9 seconds instead of 2-3 seconds, which is quite detrimental in a large scale experiment.
The slice of code that uses the matlab.engine, and which slows down on the other machine, is
for i, pred in enumerate(predictions):
original_length = dataset[i][‘length_EP’]
pred = ApplyPostProcessing(pred,original_length)
vocoded_futures[i] = eng_list[i%len(eng_list)].runVocoderPython(matlab.double(pred), nargout=2, background=True)
The "eng_list" variable is just a list of separate matlab engines I use to speed up the processing. "runVocoderPython" is just a wrapper for a matlab function that runs the vocoder.
Does anyone know what could cause this specific slowdown of the matlab.engine?
I use Python 3.8.19, Matlab 2022a and Linux as OS. I am using the matlab engine to convert stimulation patterns of cochlear implants into audio through a vocoder supplied by cochlear ltd from my python code.
My code is quite fast when I run it on my computer, the part that uses the matlab engine runs in about 2 seconds if I use 10 engines in parallel.
Now I tried to run my code in our cluster on a machine with epyc cpus, which are at least as fast as my own computer’s cpu. However, while the rest of my code runs on this cluster computer almost as fast as on my own machine – I see at most an increase by a factor of 1.2 – the matlab.engine part is slowed down by a factor of 2-3, i.e., the same code requires 8-9 seconds instead of 2-3 seconds, which is quite detrimental in a large scale experiment.
The slice of code that uses the matlab.engine, and which slows down on the other machine, is
for i, pred in enumerate(predictions):
original_length = dataset[i][‘length_EP’]
pred = ApplyPostProcessing(pred,original_length)
vocoded_futures[i] = eng_list[i%len(eng_list)].runVocoderPython(matlab.double(pred), nargout=2, background=True)
The "eng_list" variable is just a list of separate matlab engines I use to speed up the processing. "runVocoderPython" is just a wrapper for a matlab function that runs the vocoder.
Does anyone know what could cause this specific slowdown of the matlab.engine?
I use Python 3.8.19, Matlab 2022a and Linux as OS. matlab.engine, python2matlab, python MATLAB Answers — New Questions

Matlab

Funktion for a floating masspoint in 3D

/ 2024-09-26

Hey guys,
I´m new to matlab and I want you to ask you some questions.
First of all, I want to plot a floating masspoint on a 3D surface, so I try to figure out how to get the gradient, angle of the surface and at last but not least to get a differential equation.
My code looks like this:

%% paramter
h=0.0002; %
g=-9.81; %gravity
u=0.2; %friction
x0=-12;
y0=-12;

%% gradienten
fgradx = ((x0+h,y0)-(x0-h,y0))/2*h;
fgrady = ((x0,y0+h)-(x0,y0-h))/2*h;

%% angle
winkelx = atan((boden(x + h, c) – boden(x – h, c))/(2*h));
winkely = atan((boden(y + h, c) – boden(y – h, c))/(2*h));

%% Differential Equation
F=[Y(2);Y(3);cos(winkelx)*((sin(winkelx)*g*m)-(cos(winkelx)*m*g*u));cos(winkely)*((sin(winkely)*g*m)-(cos(winkely)*m*g*u))];
So I want you to know, if the code is fine or if i messed up. Would be nice, if you can give me some tips :).

Have a nice day.Hey guys,
I´m new to matlab and I want you to ask you some questions.
First of all, I want to plot a floating masspoint on a 3D surface, so I try to figure out how to get the gradient, angle of the surface and at last but not least to get a differential equation.
My code looks like this:

%% paramter
h=0.0002; %
g=-9.81; %gravity
u=0.2; %friction
x0=-12;
y0=-12;

%% gradienten
fgradx = ((x0+h,y0)-(x0-h,y0))/2*h;
fgrady = ((x0,y0+h)-(x0,y0-h))/2*h;

%% angle
winkelx = atan((boden(x + h, c) – boden(x – h, c))/(2*h));
winkely = atan((boden(y + h, c) – boden(y – h, c))/(2*h));

Have a nice day. Hey guys,
I´m new to matlab and I want you to ask you some questions.
First of all, I want to plot a floating masspoint on a 3D surface, so I try to figure out how to get the gradient, angle of the surface and at last but not least to get a differential equation.
My code looks like this:

%% paramter
h=0.0002; %
g=-9.81; %gravity
u=0.2; %friction
x0=-12;
y0=-12;

%% gradienten
fgradx = ((x0+h,y0)-(x0-h,y0))/2*h;
fgrady = ((x0,y0+h)-(x0,y0-h))/2*h;

%% angle
winkelx = atan((boden(x + h, c) – boden(x – h, c))/(2*h));
winkely = atan((boden(y + h, c) – boden(y – h, c))/(2*h));

Have a nice day. 3d plot, ball, gradient, angl, differential equations MATLAB Answers — New Questions

Matlab

measure the distance between two object

/ 2024-09-26

Hello everyone;
I detect two different objects in Yolo v4 and I want to measure the distance between them, what is the method to measure the distance
can anyone help me…Hello everyone;
I detect two different objects in Yolo v4 and I want to measure the distance between them, what is the method to measure the distance
can anyone help me… Hello everyone;
I detect two different objects in Yolo v4 and I want to measure the distance between them, what is the method to measure the distance
can anyone help me… deep learning, image processing, yolo, object detection MATLAB Answers — New Questions

Matlab

MPPT P&O Algorithm

/ 2024-09-26

Hello community;
I hope everyone is doing well. I’m trying to find an MPPT P&O algorithm.
I will be extremely appreciative of your assistance and responses.

Best regards.Hello community;
I hope everyone is doing well. I’m trying to find an MPPT P&O algorithm.
I will be extremely appreciative of your assistance and responses.

Best regards. Hello community;
I hope everyone is doing well. I’m trying to find an MPPT P&O algorithm.
I will be extremely appreciative of your assistance and responses.

Best regards. mppt-p o-algorithm MATLAB Answers — New Questions

Matlab

Plot Bode diagrams from the given closed loop system frequency responses in the table

/ 2024-09-26

I am stuck here, I am able to plot the bode diagram from a TF and yet given closed loop system frequency responses I get stumped. Is there a video or link where I can learn more about coding these types of Bode diagrams?I am stuck here, I am able to plot the bode diagram from a TF and yet given closed loop system frequency responses I get stumped. Is there a video or link where I can learn more about coding these types of Bode diagrams? I am stuck here, I am able to plot the bode diagram from a TF and yet given closed loop system frequency responses I get stumped. Is there a video or link where I can learn more about coding these types of Bode diagrams? bode diagram MATLAB Answers — New Questions

Matlab

How to read analog signal from Arduino in Matlab?

/ 2024-09-26

sir , i want the serial monitor data in Arduino to be accessed in Matlab.some people told me to use data streamer in Excel to store the data in Excel sheet but everytime when i open the excel sheet it always ask me to do some common procedure like
1.Connect a Device
2.Choose your Device to stream data
whether it is possible to make all this process in automatic manner in Matlabsir , i want the serial monitor data in Arduino to be accessed in Matlab.some people told me to use data streamer in Excel to store the data in Excel sheet but everytime when i open the excel sheet it always ask me to do some common procedure like
1.Connect a Device
2.Choose your Device to stream data
whether it is possible to make all this process in automatic manner in Matlab sir , i want the serial monitor data in Arduino to be accessed in Matlab.some people told me to use data streamer in Excel to store the data in Excel sheet but everytime when i open the excel sheet it always ask me to do some common procedure like
1.Connect a Device
2.Choose your Device to stream data
whether it is possible to make all this process in automatic manner in Matlab matlab, data, excel, data acquisition, importing excel data MATLAB Answers — New Questions

Matlab

Why i got this error and how to solve it？

/ 2024-09-26

I try to use ‘final states-save final operating piont’,but got the error:
" An error occurred while running the simulation and the simulation was terminated
Caused by:
Simulink is unable to save the operating point of the C Level-2 S-Function (sfun_Controller) block ‘***/sfun_Controller’ because the S-function has pointer work (PWork) vectors.
"
Why there are pionter vectors and how to deal with them?I try to use ‘final states-save final operating piont’,but got the error:
" An error occurred while running the simulation and the simulation was terminated
Caused by:
Simulink is unable to save the operating point of the C Level-2 S-Function (sfun_Controller) block ‘***/sfun_Controller’ because the S-function has pointer work (PWork) vectors.
"
Why there are pionter vectors and how to deal with them? I try to use ‘final states-save final operating piont’,but got the error:
" An error occurred while running the simulation and the simulation was terminated
Caused by:
Simulink is unable to save the operating point of the C Level-2 S-Function (sfun_Controller) block ‘***/sfun_Controller’ because the S-function has pointer work (PWork) vectors.
"
Why there are pionter vectors and how to deal with them? final states, save final operating piont MATLAB Answers — New Questions

Matlab

Predictive maintenance – data required for generalizing the model

/ 2024-09-26

I have gone through the video for doing predictive maintenance. (https://www.mathworks.com/videos/predictive-maintenance-part-1-introduction-1545827554336.html). I understand that for doing predictive maintenance in that video, sensor input from 100 machines were used.
I would like to know to generalize a model to do predictive maintenace using user sensor data, data of how many machines I need to use to train/validate the model? How to find how many machine data required, so that model is generalized. Can you please supportI have gone through the video for doing predictive maintenance. (https://www.mathworks.com/videos/predictive-maintenance-part-1-introduction-1545827554336.html). I understand that for doing predictive maintenance in that video, sensor input from 100 machines were used.
I would like to know to generalize a model to do predictive maintenace using user sensor data, data of how many machines I need to use to train/validate the model? How to find how many machine data required, so that model is generalized. Can you please support I have gone through the video for doing predictive maintenance. (https://www.mathworks.com/videos/predictive-maintenance-part-1-introduction-1545827554336.html). I understand that for doing predictive maintenance in that video, sensor input from 100 machines were used.
I would like to know to generalize a model to do predictive maintenace using user sensor data, data of how many machines I need to use to train/validate the model? How to find how many machine data required, so that model is generalized. Can you please support predictive maintenace, sensor data, deep learning MATLAB Answers — New Questions

Matlab

How to achieved Matlab code for high precision, recall and F-measure values in ANN or PNN ?

/ 2024-09-26

In My Project whitefly and Thrip identification algorithm achieved high precision, recall and F-measure values. The Algorithm is ANN and PNN Both…

My Paper Title is " Combination of image processing and artificial neural networks as a novel approach for the identification of Bemisia tabaci and Frankliniella occidentalis on sticky traps in greenhouse agriculture "

I neead a MATLAB Code for given parameters… How to find this parameters values in both ANN and PNN via MATLAB CODE??In My Project whitefly and Thrip identification algorithm achieved high precision, recall and F-measure values. The Algorithm is ANN and PNN Both…

I neead a MATLAB Code for given parameters… How to find this parameters values in both ANN and PNN via MATLAB CODE?? In My Project whitefly and Thrip identification algorithm achieved high precision, recall and F-measure values. The Algorithm is ANN and PNN Both…

I neead a MATLAB Code for given parameters… How to find this parameters values in both ANN and PNN via MATLAB CODE?? classification, neural networks, image processing MATLAB Answers — New Questions

Matlab

How to solve the system of time dependent coupled PDE’s?

/ 2024-09-26

The system this paper (DOI: 10.1017/S0022112003003835) Thank you.
Fig10a(0.2,2050)
function Fig10a(delta, Reynolds)
% Main function to solve for F and G and plot G(1/4, t)

% Initialize variables
R = Reynolds;
dt = 1/10;
nmax = 82001;
dy = 1/100;
yTarget = 1/4;
gValues = [];

Delta = delta;
H = @(t) 1 + Delta * cos(2 * t);
dH = @(t) -2 * Delta * sin(2 * t);

% Create the grid and differentiation matrices
ygrid = 0:dy:1;
ny = length(ygrid);

% Finite difference differentiation matrices (for dy1 and dy2)
dy2 = fdcoeffFDM2(ny, dy); % Second-order finite difference matrix
dy1 = fdcoeffFDM1(ny, dy); % First-order finite difference matrix

% Initialize variables for F and G
fvar0 = zeros(ny, nmax);
gvar0 = zeros(ny, nmax);

% Time-stepping loop
for i = 1:nmax-1
% Update variables for F and G at the current time step
fvar = fvar0(:, i);
gvar = gvar0(:, i);

% Define the equations
eqf = dy2 * fvar + (dy1 * fvar)./ygrid’ – fvar./(ygrid’.^2) + …
gvar * H((i + 1) * dt)^2;
eqg = (gvar – gvar0(:, i)) / dt – …
dH((i + 1) * dt) / H((i + 1) * dt) * (dy1 * gvar)./ygrid’ – …
(dy1 * gvar) .* fvar / H((i + 1) * dt) + …
1/H((i + 1) * dt) * (dy1 * fvar) .* gvar + …
2./(ygrid’ * H((i + 1) * dt)) .* fvar .* gvar – …
(1/(R * H((i + 1) * dt)^2)) * (dy2 * gvar + dy1 * gvar./ygrid’ – gvar./(ygrid’.^2));

% Apply boundary conditions
eqf(1) = fvar(1); % F(0, t) = 0 at y = 0
eqf(end) = fvar(end) + dH((i + 1) * dt); % F(1, t) = -H'(t) at y = 1
eqg(1) = gvar(1); % G(0, t) = 0 at t = 0
eqg(end) = dy1(end, 🙂 * fvar – dH((i + 1) * dt); % F'(1, t) = H'(t) at y = 1

% Combine eqf and eqg into a single system
eqns = [eqf; eqg];

% Solve the system using backslash operator
sol = eqns; % Since we are already evaluating eqns as the result

% Check that the solution vector matches the expected size
if length(sol) ~= 2 * ny
error(‘The number of equations does not match the number of unknowns’);
end

% Update variables for the next step
fvar0(:, i+1) = sol(1:ny);
gvar0(:, i+1) = sol(ny+1:end);

% Interpolate G(y, t) and store G(1/4, t)
if i >= 81000 && i <= 82001
gInterp = interp1(ygrid, gvar0(:, i+1), yTarget);
gValues = [gValues; i, gInterp];
end

% Display debugging information every 1000 iterations
if mod(i, 1000) == 0 & i>=81000
disp([‘Iteration: ‘, num2str(i), ‘ | G(1/4, t): ‘, num2str(gInterp)]);
end
end

% Plot the values of G(1/4, t)
figure;
if isempty(gValues)
disp(‘No values of G(1/4, t) were recorded.’);
else
plot(gValues(:,1), gValues(:,2), ‘r-‘, ‘LineWidth’, 2);
grid on;
xlabel(‘t’);
ylabel(‘G(1/4, t)’);
title(‘G(1/4, t) from t = 8100 to t = 8200’);
end
end

% Auxiliary function for second-order finite difference matrix
function D2 = fdcoeffFDM2(ny, dy)
e = ones(ny, 1);
D2 = spdiags([e -2*e e], -1:1, ny, ny) / (dy^2);
D2(1, 🙂 = 0; D2(end, 🙂 = 0; % Apply boundary conditions
end

% Auxiliary function for first-order finite difference matrix
function D1 = fdcoeffFDM1(ny, dy)
e = ones(ny, 1);
D1 = spdiags([-e e], [-1 1], ny, ny) / (2*dy);
D1(1, 🙂 = 0; D1(end, 🙂 = 0; % Apply boundary conditions
endThe system this paper (DOI: 10.1017/S0022112003003835) Thank you.
Fig10a(0.2,2050)
function Fig10a(delta, Reynolds)
% Main function to solve for F and G and plot G(1/4, t)