According to MathWorks documentation of the Random Number block, "variance" input is the variance of the normally distributed random numbers.
Thus, you can provide the square of the standard deviation as input.
To verify this, you can connect the Random Number Block configured with the appropriate mean and variance values to a To Workspace Simulink block. This block logs the Simulink block output to the MATLAB workspace.
Next you can use the "sim" function in MATLAB which is used to run the Simulink model programmatically in a MATLAB script. You may then use the "var" function in MATLAB to compute the variance of the generated data. Kindly refer to the MATLAB code snippet below to do so:
out = sim("randomNumberBlock.slx");
variance = var(out.simout.Data);
For more information on the Simulink blocks and MATLAB functions, please refer to the MathWorks documentation linked below:
- Random Number Block: https://www.mathworks.com/help/simulink/slref/randomnumber.html
- To Workspace Block: https://www.mathworks.com/help/simulink/slref/toworkspace.html
- sim: https://www.mathworks.com/help/simulink/slref/sim.html
I hope this is helpful!
