EMG signal processing ADC plot showing error .

when i try process the acquired EMG signal i cant get the ADC PLOT.

when i try to run it shows the error (below mentioned inside the double quotation block letters)

"Index exceeds the number of array elements. Index must not exceed 15153.

Error in Main_Code_REVISED (line 38)

plot(t, xt(1:40000), 'b.-','LineWidth', 2,'MarkerSize', 15);% plot the signal

>> "

Here i added the code for reference

%% ------------------------------------------------ ****** ADC At Sample Rate ****** ---------------------------------------%

% Sampling rate is 400 Hz, or one sample every 1/400 of a second.

% Number of Samples = (elasped time) / (time per sample)

numSamples = round(10^2/(1/400)); % Round towards nearest integer.

% That is only 40000 and gives a severe undersampling of the signal

% giving a weird shape.

t = linspace(0, 0.1, numSamples);%generates N points between X1 and X2.

xt = filtered_sig1; % Assigned bpf output signal

figure(3)% open a figure in new window

plot(t, xt(1:40000), 'b.-','LineWidth', 2,'MarkerSize', 15);% plot the signal

grid on;% adds major grid lines to the current axes.

title('sampling Interval'); % Graph title

xlabel('t'); % X-axis label.

ylabel('x(t)');% Y-axis label.

Answer 1

[Sai Pavan]

Hi Athikesavan,

I understand that you are trying to resolve the error encountered when plotting the filtered signal.

The "Index exceeds the number of array elements” error suggests that the index used for slicing the “xt” array exceeds the number of elements in the array. The error message indicates that there are only 15153 samples stored in the variable “xt”, but you are trying to access elements up to index 40000.

The two arguments of the “plot” function must be of the same size. The error can therefore be resolved either by collecting more samples (“numSamples”) up to 40000 or, by slicing the “t” (sampling time) array to 15153 samples and then plotting the signal so that the two arguments of the function match.

Please refer the below documentation to learn more about “plot” function: https://www.mathworks.com/help/matlab/ref/plot.html

Hope it helps.

Regards,

Sai Pavan