I’ve generated an MATLAB code based on these pointed problems, such that:
Q: Consider a 2D 3-story shear building model.
1. Form the mass and stiffness matrices for this building model. No damping in needed for this problem.
2. Using trial and errors, select meaningful story mass and stiffness parameters so that the first natural frequency of the building is 1 sec. Consider that the story mass and stiffness values are similar among the three stories; therefore, you need to set only one stiffness and one mass parameter. Use your engineering judgement and explain your logic. Find and plot the mode shapes of the building model.
3. Implement a Newmark-beta algorithm for time integration of the dynamic equilibrium equation. Use a unidirectional earthquake base excitation as input and solve for the acceleration response at the three DOFs. For the earthquake base excitation, use this input file with a sampling frequency of 100 Hz. Plot the time history of absolute acceleration response at each floor.
4. Resample the input signal at 20, 10, and 2 Hz and redo steps 4-5 with integration time step size of 0.05, 0.1, and 0.5 sec, respectively. Compare the results and explain your observations.

MATLAB CODE
—————————————————————————————————————–
clear all;
clc;
close all;
%% INPUT Parameters:
m = 1; % Initial arbitrary mass of each story
k = 1; % Initial arbitrary stiffness of each story
%% Solution-1: Form Mass and Stiffness Matrices
M = m * eye(3); % Mass matrix
K = [ 2*k, -k, 0; -k, 2*k, -k; 0, -k, k]; % Stiffness matrix
%% Solution-2: Adjust Mass and Stiffness based on target frequency
target_frequency = 1; % Natural Frequency (Hz)
target_omega = 2 * pi * target_frequency; % Angular Frequency (rad/s)
% Adjust stiffness based on the target frequency
k = target_omega^2 * m / 2;
K = [ 2*k, -k, 0; -k, 2*k, -k; 0, -k, k]; % Updated Stiffness matrix
%% Solution-3: Find and Plot Mode Shapes
[eigVectors, eigValues] = eig(K, M); % Solve eigenvalue problem
omega = sqrt(diag(eigValues)); % Natural frequencies (rad/s)
figure;
for i = 1:3
subplot(3, 1, i);
plot([0 eigVectors(:,i)’], ‘o-‘); % Plot mode shapes
title([‘Mode Shape ‘, num2str(i)]);
xlabel(‘Story’);
ylabel(‘Displacement’);
end
%% Solution-4: Implement Newmark-beta algorithm for dynamic analysis
% Parameters for Newmark-beta
beta = 1/4;
gamma = 1/2;
% Load earthquake data
data = load(‘CNP100.txt’); % Load earthquake data
dt = 0.01; % Sampling interval for 100 Hz
time = (0:length(data)-1)*dt;
% Initial conditions
u = zeros(3, 1); % Initial displacement
v = zeros(3, 1); % Initial velocity
a = M ((data(1) * ones(3, 1)) – K*u); % Initial acceleration
% Time integration using Newmark-beta method
u_history = zeros(3, length(time));
a_history = zeros(3, length(time));
a_history(:, 1) = a;
for i = 1:length(time)-1
% Predictors
u_pred = u + (dt * v) + ((dt^2) * (0.5-beta) * a);
v_pred = v + (dt * (1-gamma) * a);

% Solve for acceleration
a_new = M ((data(i+1) * ones(3, 1)) – (K * u_pred));

% Correctors
u = u_pred + (beta * (dt^2) * a_new);
v = v_pred + (gamma * dt * a_new);

% Store response
u_history(:, i+1) = u;
a_history(:, i+1) = a_new;
a = a_new;
end
%% Solution-5: Plot time history of absolute acceleration response
figure;
for i = 1:3
subplot(3, 1, i);
plot(time, a_history(i, :));
title([‘Absolute Acceleration Response Sampled at 100 Hz at DOF ‘, num2str(i)]);
xlabel(‘Time (s)’);
ylabel(‘Acceleration (m/s^2)’);
end
%% Solution-6: Resample input signal and repeat the analysis
frequencies = [20, 10, 2];
time_steps = [0.05, 0.1, 0.5];
for j = 1:length(frequencies)
new_fs = frequencies(j);
new_dt = 1/new_fs;
new_data = resample(data, new_fs, 100);
new_time = (0:length(new_data)-1)*new_dt;

% Repeat the Newmark-beta integration with new data
u = zeros(3, 1); % Initial displacement
v = zeros(3, 1); % Initial velocity
a = M ((new_data(1) * ones(3, 1)) – K*u); % Initial acceleration

u_history = zeros(3, length(new_time));
a_history = zeros(3, length(new_time));
a_history(:, 1) = a;

for i = 1:length(new_time)-1
% Predictors
u_pred = u + (new_dt * v) + ((new_dt^2) * (0.5-beta) * a);
v_pred = v + (new_dt * (1-gamma) * a);

% Solve for acceleration
a_new = M ((new_data(i+1) * ones(3, 1)) – K * u_pred);

% Correctors
u = u_pred + (beta * (new_dt^2) * a_new);
v = v_pred + (gamma * new_dt * a_new);

% Store response
u_history(:, i+1) = u;
a_history(:, i+1) = a_new;
a = a_new;
end

% Plot time history of absolute acceleration response
figure;
for i = 1:3
subplot(3, 1, i);
plot(new_time, a_history(i, :));
title([‘Absolute Acceleration Response at DOF ‘, num2str(i), ‘ (Resampled at ‘, num2str(new_fs), ‘ Hz)’]);
xlabel(‘Time (s)’);
ylabel(‘Acceleration (m/s^2)’);
end
end
——————————————————————————————————————–
I’m getting error in obtaining:
The first modal period as 1 second.
The correct Newmark Beta plots.I’ve generated an MATLAB code based on these pointed problems, such that:
Q: Consider a 2D 3-story shear building model.
1. Form the mass and stiffness matrices for this building model. No damping in needed for this problem.
2. Using trial and errors, select meaningful story mass and stiffness parameters so that the first natural frequency of the building is 1 sec. Consider that the story mass and stiffness values are similar among the three stories; therefore, you need to set only one stiffness and one mass parameter. Use your engineering judgement and explain your logic. Find and plot the mode shapes of the building model.
3. Implement a Newmark-beta algorithm for time integration of the dynamic equilibrium equation. Use a unidirectional earthquake base excitation as input and solve for the acceleration response at the three DOFs. For the earthquake base excitation, use this input file with a sampling frequency of 100 Hz. Plot the time history of absolute acceleration response at each floor.
4. Resample the input signal at 20, 10, and 2 Hz and redo steps 4-5 with integration time step size of 0.05, 0.1, and 0.5 sec, respectively. Compare the results and explain your observations.

MATLAB CODE
—————————————————————————————————————–
clear all;
clc;
close all;
%% INPUT Parameters:
m = 1; % Initial arbitrary mass of each story
k = 1; % Initial arbitrary stiffness of each story
%% Solution-1: Form Mass and Stiffness Matrices
M = m * eye(3); % Mass matrix
K = [ 2*k, -k, 0; -k, 2*k, -k; 0, -k, k]; % Stiffness matrix
%% Solution-2: Adjust Mass and Stiffness based on target frequency
target_frequency = 1; % Natural Frequency (Hz)
target_omega = 2 * pi * target_frequency; % Angular Frequency (rad/s)
% Adjust stiffness based on the target frequency
k = target_omega^2 * m / 2;
K = [ 2*k, -k, 0; -k, 2*k, -k; 0, -k, k]; % Updated Stiffness matrix
%% Solution-3: Find and Plot Mode Shapes
[eigVectors, eigValues] = eig(K, M); % Solve eigenvalue problem
omega = sqrt(diag(eigValues)); % Natural frequencies (rad/s)
figure;
for i = 1:3
subplot(3, 1, i);
plot([0 eigVectors(:,i)’], ‘o-‘); % Plot mode shapes
title([‘Mode Shape ‘, num2str(i)]);
xlabel(‘Story’);
ylabel(‘Displacement’);
end
%% Solution-4: Implement Newmark-beta algorithm for dynamic analysis
% Parameters for Newmark-beta
beta = 1/4;
gamma = 1/2;
% Load earthquake data
data = load(‘CNP100.txt’); % Load earthquake data
dt = 0.01; % Sampling interval for 100 Hz
time = (0:length(data)-1)*dt;
% Initial conditions
u = zeros(3, 1); % Initial displacement
v = zeros(3, 1); % Initial velocity
a = M ((data(1) * ones(3, 1)) – K*u); % Initial acceleration
% Time integration using Newmark-beta method
u_history = zeros(3, length(time));
a_history = zeros(3, length(time));
a_history(:, 1) = a;
for i = 1:length(time)-1
% Predictors
u_pred = u + (dt * v) + ((dt^2) * (0.5-beta) * a);
v_pred = v + (dt * (1-gamma) * a);

% Solve for acceleration
a_new = M ((data(i+1) * ones(3, 1)) – (K * u_pred));

% Correctors
u = u_pred + (beta * (dt^2) * a_new);
v = v_pred + (gamma * dt * a_new);

% Store response
u_history(:, i+1) = u;
a_history(:, i+1) = a_new;
a = a_new;
end
%% Solution-5: Plot time history of absolute acceleration response
figure;
for i = 1:3
subplot(3, 1, i);
plot(time, a_history(i, :));
title([‘Absolute Acceleration Response Sampled at 100 Hz at DOF ‘, num2str(i)]);
xlabel(‘Time (s)’);
ylabel(‘Acceleration (m/s^2)’);
end
%% Solution-6: Resample input signal and repeat the analysis
frequencies = [20, 10, 2];
time_steps = [0.05, 0.1, 0.5];
for j = 1:length(frequencies)
new_fs = frequencies(j);
new_dt = 1/new_fs;
new_data = resample(data, new_fs, 100);
new_time = (0:length(new_data)-1)*new_dt;

% Repeat the Newmark-beta integration with new data
u = zeros(3, 1); % Initial displacement
v = zeros(3, 1); % Initial velocity
a = M ((new_data(1) * ones(3, 1)) – K*u); % Initial acceleration

u_history = zeros(3, length(new_time));
a_history = zeros(3, length(new_time));
a_history(:, 1) = a;

for i = 1:length(new_time)-1
% Predictors
u_pred = u + (new_dt * v) + ((new_dt^2) * (0.5-beta) * a);
v_pred = v + (new_dt * (1-gamma) * a);

% Solve for acceleration
a_new = M ((new_data(i+1) * ones(3, 1)) – K * u_pred);

% Correctors
u = u_pred + (beta * (new_dt^2) * a_new);
v = v_pred + (gamma * new_dt * a_new);

% Store response
u_history(:, i+1) = u;
a_history(:, i+1) = a_new;
a = a_new;
end

% Plot time history of absolute acceleration response
figure;
for i = 1:3
subplot(3, 1, i);
plot(new_time, a_history(i, :));
title([‘Absolute Acceleration Response at DOF ‘, num2str(i), ‘ (Resampled at ‘, num2str(new_fs), ‘ Hz)’]);
xlabel(‘Time (s)’);
ylabel(‘Acceleration (m/s^2)’);
end
end
——————————————————————————————————————–
I’m getting error in obtaining:
The first modal period as 1 second.
The correct Newmark Beta plots. I’ve generated an MATLAB code based on these pointed problems, such that:
Q: Consider a 2D 3-story shear building model.
1. Form the mass and stiffness matrices for this building model. No damping in needed for this problem.
2. Using trial and errors, select meaningful story mass and stiffness parameters so that the first natural frequency of the building is 1 sec. Consider that the story mass and stiffness values are similar among the three stories; therefore, you need to set only one stiffness and one mass parameter. Use your engineering judgement and explain your logic. Find and plot the mode shapes of the building model.
3. Implement a Newmark-beta algorithm for time integration of the dynamic equilibrium equation. Use a unidirectional earthquake base excitation as input and solve for the acceleration response at the three DOFs. For the earthquake base excitation, use this input file with a sampling frequency of 100 Hz. Plot the time history of absolute acceleration response at each floor.
4. Resample the input signal at 20, 10, and 2 Hz and redo steps 4-5 with integration time step size of 0.05, 0.1, and 0.5 sec, respectively. Compare the results and explain your observations.

MATLAB CODE
—————————————————————————————————————–
clear all;
clc;
close all;
%% INPUT Parameters:
m = 1; % Initial arbitrary mass of each story
k = 1; % Initial arbitrary stiffness of each story
%% Solution-1: Form Mass and Stiffness Matrices
M = m * eye(3); % Mass matrix
K = [ 2*k, -k, 0; -k, 2*k, -k; 0, -k, k]; % Stiffness matrix
%% Solution-2: Adjust Mass and Stiffness based on target frequency
target_frequency = 1; % Natural Frequency (Hz)
target_omega = 2 * pi * target_frequency; % Angular Frequency (rad/s)
% Adjust stiffness based on the target frequency
k = target_omega^2 * m / 2;
K = [ 2*k, -k, 0; -k, 2*k, -k; 0, -k, k]; % Updated Stiffness matrix
%% Solution-3: Find and Plot Mode Shapes
[eigVectors, eigValues] = eig(K, M); % Solve eigenvalue problem
omega = sqrt(diag(eigValues)); % Natural frequencies (rad/s)
figure;
for i = 1:3
subplot(3, 1, i);
plot([0 eigVectors(:,i)’], ‘o-‘); % Plot mode shapes
title([‘Mode Shape ‘, num2str(i)]);
xlabel(‘Story’);
ylabel(‘Displacement’);
end
%% Solution-4: Implement Newmark-beta algorithm for dynamic analysis
% Parameters for Newmark-beta
beta = 1/4;
gamma = 1/2;
% Load earthquake data
data = load(‘CNP100.txt’); % Load earthquake data
dt = 0.01; % Sampling interval for 100 Hz
time = (0:length(data)-1)*dt;
% Initial conditions
u = zeros(3, 1); % Initial displacement
v = zeros(3, 1); % Initial velocity
a = M ((data(1) * ones(3, 1)) – K*u); % Initial acceleration
% Time integration using Newmark-beta method
u_history = zeros(3, length(time));
a_history = zeros(3, length(time));
a_history(:, 1) = a;
for i = 1:length(time)-1
% Predictors
u_pred = u + (dt * v) + ((dt^2) * (0.5-beta) * a);
v_pred = v + (dt * (1-gamma) * a);

% Solve for acceleration
a_new = M ((data(i+1) * ones(3, 1)) – (K * u_pred));

% Correctors
u = u_pred + (beta * (dt^2) * a_new);
v = v_pred + (gamma * dt * a_new);

% Store response
u_history(:, i+1) = u;
a_history(:, i+1) = a_new;
a = a_new;
end
%% Solution-5: Plot time history of absolute acceleration response
figure;
for i = 1:3
subplot(3, 1, i);
plot(time, a_history(i, :));
title([‘Absolute Acceleration Response Sampled at 100 Hz at DOF ‘, num2str(i)]);
xlabel(‘Time (s)’);
ylabel(‘Acceleration (m/s^2)’);
end
%% Solution-6: Resample input signal and repeat the analysis
frequencies = [20, 10, 2];
time_steps = [0.05, 0.1, 0.5];
for j = 1:length(frequencies)
new_fs = frequencies(j);
new_dt = 1/new_fs;
new_data = resample(data, new_fs, 100);
new_time = (0:length(new_data)-1)*new_dt;

% Repeat the Newmark-beta integration with new data
u = zeros(3, 1); % Initial displacement
v = zeros(3, 1); % Initial velocity
a = M ((new_data(1) * ones(3, 1)) – K*u); % Initial acceleration

u_history = zeros(3, length(new_time));
a_history = zeros(3, length(new_time));
a_history(:, 1) = a;

for i = 1:length(new_time)-1
% Predictors
u_pred = u + (new_dt * v) + ((new_dt^2) * (0.5-beta) * a);
v_pred = v + (new_dt * (1-gamma) * a);

% Solve for acceleration
a_new = M ((new_data(i+1) * ones(3, 1)) – K * u_pred);

% Correctors
u = u_pred + (beta * (new_dt^2) * a_new);
v = v_pred + (gamma * new_dt * a_new);

% Store response
u_history(:, i+1) = u;
a_history(:, i+1) = a_new;
a = a_new;
end

% Plot time history of absolute acceleration response
figure;
for i = 1:3
subplot(3, 1, i);
plot(new_time, a_history(i, :));
title([‘Absolute Acceleration Response at DOF ‘, num2str(i), ‘ (Resampled at ‘, num2str(new_fs), ‘ Hz)’]);
xlabel(‘Time (s)’);
ylabel(‘Acceleration (m/s^2)’);
end
end
——————————————————————————————————————–
I’m getting error in obtaining:
The first modal period as 1 second.
The correct Newmark Beta plots. newmarkbeta, modalperiod, structuraldynamics MATLAB Answers — New Questions

​

I keep on getting this error when trying to run on server.

java.lang.NoClassDefFoundError: Could not initialize class com.mathworks.toolbox.javabuilder.internal.MWMCR
com.mathworks.toolbox.javabuilder.MWUtil.GetUnknownClassID(MWUtil.java:727)
com.mathworks.toolbox.javabuilder.MWClassID.<clinit>(MWClassID.java:41)
SingleDose.doGet(SingleDose.java:63)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51

Can somebody please explain what should I do? I dont have problem to run the .jsp file. The error will come only when I try to simulate the webfigure.

*Work done:* Install SDK, mex -setup, install MCR, putting javabuilder.jar in Tomcat lib, set environment for JAVA_HOME JAVA_JRE CLASSPATH Path CATALINA_HOME.I keep on getting this error when trying to run on server.

java.lang.NoClassDefFoundError: Could not initialize class com.mathworks.toolbox.javabuilder.internal.MWMCR
com.mathworks.toolbox.javabuilder.MWUtil.GetUnknownClassID(MWUtil.java:727)
com.mathworks.toolbox.javabuilder.MWClassID.<clinit>(MWClassID.java:41)
SingleDose.doGet(SingleDose.java:63)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51

Can somebody please explain what should I do? I dont have problem to run the .jsp file. The error will come only when I try to simulate the webfigure.

*Work done:* Install SDK, mex -setup, install MCR, putting javabuilder.jar in Tomcat lib, set environment for JAVA_HOME JAVA_JRE CLASSPATH Path CATALINA_HOME. I keep on getting this error when trying to run on server.

java.lang.NoClassDefFoundError: Could not initialize class com.mathworks.toolbox.javabuilder.internal.MWMCR
com.mathworks.toolbox.javabuilder.MWUtil.GetUnknownClassID(MWUtil.java:727)
com.mathworks.toolbox.javabuilder.MWClassID.<clinit>(MWClassID.java:41)
SingleDose.doGet(SingleDose.java:63)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51

Can somebody please explain what should I do? I dont have problem to run the .jsp file. The error will come only when I try to simulate the webfigure.

*Work done:* Install SDK, mex -setup, install MCR, putting javabuilder.jar in Tomcat lib, set environment for JAVA_HOME JAVA_JRE CLASSPATH Path CATALINA_HOME. java, webfigure MATLAB Answers — New Questions

​

Hi all,

I have a set of X,Y,Z data where X and Y represent coordinates and Z the corresponding elevation. How can I now plot a 2D image with the projection of the 3D surface on it?

In stead of:

<<https://www.researchgate.net/profile/M_Hennessey/publication/267491866/figure/fig4/AS:295759909015586@1447526065926/FIGURE-4-LONE-MOUNTAIN-CHARACTERIZED-USING-THE-R-3D-MATLAB-INTERP2-COMMAND-AND-DEM-DATA.png>>

I’d like to have something like this:

<<http://cn.mathworks.com/matlabcentral/mlc-downloads/downloads/submissions/19791/versions/2/screenshot.jpg>>

Thanks!Hi all,

I have a set of X,Y,Z data where X and Y represent coordinates and Z the corresponding elevation. How can I now plot a 2D image with the projection of the 3D surface on it?

In stead of:

<<https://www.researchgate.net/profile/M_Hennessey/publication/267491866/figure/fig4/AS:295759909015586@1447526065926/FIGURE-4-LONE-MOUNTAIN-CHARACTERIZED-USING-THE-R-3D-MATLAB-INTERP2-COMMAND-AND-DEM-DATA.png>>

I’d like to have something like this:

<<http://cn.mathworks.com/matlabcentral/mlc-downloads/downloads/submissions/19791/versions/2/screenshot.jpg>>

Thanks! Hi all,

I have a set of X,Y,Z data where X and Y represent coordinates and Z the corresponding elevation. How can I now plot a 2D image with the projection of the 3D surface on it?

In stead of:

<<https://www.researchgate.net/profile/M_Hennessey/publication/267491866/figure/fig4/AS:295759909015586@1447526065926/FIGURE-4-LONE-MOUNTAIN-CHARACTERIZED-USING-THE-R-3D-MATLAB-INTERP2-COMMAND-AND-DEM-DATA.png>>

I’d like to have something like this:

<<http://cn.mathworks.com/matlabcentral/mlc-downloads/downloads/submissions/19791/versions/2/screenshot.jpg>>

Thanks! matlab, 3d plots MATLAB Answers — New Questions

​

Helllo,
I would like to write to the Metadat of my channel but I cna’t get it to work. as a test , I tried wiriting to the Status which works.
if fieldName = "status"; is changed to fieldName = "metadata"; it doesn’t work! does anyone know the trick for getting this to work?
code here:
%keys & ID here …

thingSpeakURL = "http://api.thingspeak.com/";
thingSpeakWriteURL = thingSpeakURL + "update";

fieldName = "status";
fieldValue = ‘[100 100 100 92 93 93 94 ; 55 55 56 57 58 63 64 ; 333 444 555 666 777 888 999]’;
response = webwrite(thingSpeakWriteURL,"api_key",writeApiKey,fieldName,fieldValue);Helllo,
I would like to write to the Metadat of my channel but I cna’t get it to work. as a test , I tried wiriting to the Status which works.
if fieldName = "status"; is changed to fieldName = "metadata"; it doesn’t work! does anyone know the trick for getting this to work?
code here:
%keys & ID here …

thingSpeakURL = "http://api.thingspeak.com/";
thingSpeakWriteURL = thingSpeakURL + "update";

fieldName = "status";
fieldValue = ‘[100 100 100 92 93 93 94 ; 55 55 56 57 58 63 64 ; 333 444 555 666 777 888 999]’;
response = webwrite(thingSpeakWriteURL,"api_key",writeApiKey,fieldName,fieldValue); Helllo,
I would like to write to the Metadat of my channel but I cna’t get it to work. as a test , I tried wiriting to the Status which works.
if fieldName = "status"; is changed to fieldName = "metadata"; it doesn’t work! does anyone know the trick for getting this to work?
code here:
%keys & ID here …

thingSpeakURL = "http://api.thingspeak.com/";
thingSpeakWriteURL = thingSpeakURL + "update";

fieldName = "status";
fieldValue = ‘[100 100 100 92 93 93 94 ; 55 55 56 57 58 63 64 ; 333 444 555 666 777 888 999]’;
response = webwrite(thingSpeakWriteURL,"api_key",writeApiKey,fieldName,fieldValue); webwrite metadata MATLAB Answers — New Questions

​

I use USB-devices that create virtual serial ports in Windows, for instance COM5. When MATLAB opens a connection with one of these devices and the device disconnects and reconnects, I am unable to use the device any more. What can I do to regain access to the device?

ERROR: myComPort = serial(‘COM5’);fopen(myComPort);% now disconnect the device
% now connect the device again, the following will be unsuccessful:delete(myComPort)
clear myComPortmyComPort = serial(‘COM5’);fopen(myComPort);Error using serial/fopen (line 72)
Open failed: Port: COM5 is not available. Available ports: COM1, COM3.
Use INSTRFIND to determine if other instrument objects are connected to the requested device.I use USB-devices that create virtual serial ports in Windows, for instance COM5. When MATLAB opens a connection with one of these devices and the device disconnects and reconnects, I am unable to use the device any more. What can I do to regain access to the device?

ERROR: myComPort = serial(‘COM5’);fopen(myComPort);% now disconnect the device
% now connect the device again, the following will be unsuccessful:delete(myComPort)
clear myComPortmyComPort = serial(‘COM5’);fopen(myComPort);Error using serial/fopen (line 72)
Open failed: Port: COM5 is not available. Available ports: COM1, COM3.
Use INSTRFIND to determine if other instrument objects are connected to the requested device. I use USB-devices that create virtual serial ports in Windows, for instance COM5. When MATLAB opens a connection with one of these devices and the device disconnects and reconnects, I am unable to use the device any more. What can I do to regain access to the device?

ERROR: myComPort = serial(‘COM5’);fopen(myComPort);% now disconnect the device
% now connect the device again, the following will be unsuccessful:delete(myComPort)
clear myComPortmyComPort = serial(‘COM5’);fopen(myComPort);Error using serial/fopen (line 72)
Open failed: Port: COM5 is not available. Available ports: COM1, COM3.
Use INSTRFIND to determine if other instrument objects are connected to the requested device. serial, reconnect MATLAB Answers — New Questions

​

Why do I receive the following error when trying to connect to Arduino Hardware with the MATLAB support package?

ERROR: Failed to open serial port COM6 to communicate with board Uno. Make
sure there is no other MATLAB arduino object for this board. For
troubleshooting, see Arduino Hardware Troubleshooting.
Correspondingly using the Simulink Support Package for Arduino, why do I receive the following error when building a model for the Arduino?

ERROR: Open fail: Port: COM* is not available. No ports are available.
Use INSTRFIND to determine if other instrument objects are connected to the requested device.Why do I receive the following error when trying to connect to Arduino Hardware with the MATLAB support package?

ERROR: Failed to open serial port COM6 to communicate with board Uno. Make
sure there is no other MATLAB arduino object for this board. For
troubleshooting, see Arduino Hardware Troubleshooting.
Correspondingly using the Simulink Support Package for Arduino, why do I receive the following error when building a model for the Arduino?

ERROR: Open fail: Port: COM* is not available. No ports are available.
Use INSTRFIND to determine if other instrument objects are connected to the requested device. Why do I receive the following error when trying to connect to Arduino Hardware with the MATLAB support package?

ERROR: Failed to open serial port COM6 to communicate with board Uno. Make
sure there is no other MATLAB arduino object for this board. For
troubleshooting, see Arduino Hardware Troubleshooting.
Correspondingly using the Simulink Support Package for Arduino, why do I receive the following error when building a model for the Arduino?

ERROR: Open fail: Port: COM* is not available. No ports are available.
Use INSTRFIND to determine if other instrument objects are connected to the requested device.  MATLAB Answers — New Questions

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