exponential curve

Hi, could someone help me. How to model exponential curve in simulink. For example e^x where x is a variation which can be change. Which blocks should be used?

Thanks

Answer 1

[Paulo Silva]

From the User-Defined Functions use the MATLAB Fcn, the code you should put in that block is

exp(u(1))

Now for input try the Ramp block from Sources

Another block that does the e^x is on the Math Operations, it's the Math Function block.

[Jan]

thanks a lot,

and how about inverted function. The curve is not going to infinite in axis y but in axis x?

[Paulo Silva]

What's that inverted function?

[Paulo Silva]

is it 1/exp(u(1))?

[Jan]

i don't know exactly, the curve starts at zero and grows till it's constant on y axis so goes to infinite in x axis.

Sorry for complicated explanation, but I don't know how to say it :)

[Paulo Silva]

do you know the mathematical expression?

By your description it looks like a saturated signal

[Jan]

no i don't know the mathematical expresion.

Yes it could be saturated signal. I have done something with transfer fcn, but if I don't know coefficients how to reach it. I just want to change input signal or some parameters to gain the curve and it's changing.