Index exceeds array dimensions when inputting time = 0

I don't understand why I get this error, what does it mean that my array range is [1-1]?

Warning:Discontinuities detected within algebraic loop(s), may have trouble solving

Error:An error occurred while running the simulation and the simulation was terminated

Caused by:

Index exceeds array dimensions. Index value 0 exceeds valid range [1-1] of array u.

Error in 'DCDC/Pbase' (line 3)

y = u(1-exp(-t/0.001));

[Sindar]

What is 'u'? Matlab seems to think it is a 1x1 array (with a valid range of indices from 1 to 1). So, if you pass [1-exp(-t/0.001) = 0] to it, you are trying to access the zeroth element, which does not exist

Answer 1

[Ameer Hamza]

From the description of the error message, it appears that you are trying to solve an ODE in Simulink. In that case, my guess is that you are trying to multiply u with the exponential term. Correct it like this

y = u*(1-exp(-t/0.001));

On the off-chance that 'u' is the unit step function, you can use heaviside function(): https://www.mathworks.com/help/releases/R2020a/symbolic/heaviside.html

[JACOB SHELDRAKE]

All these years and it still gets me, thanks man.

[Ameer Hamza]

I am glad to be of help.