Problems with Inverse laplace and step function

[Roschee]

Hello,

I make an calculation of an antenna circuit. For this I have to use the step function. When I want to

make the inverselaplace function to my equation, it will not be work.

I think this will not be work, because I think that matcad will calculate values from t<0. But I want to

analyse only values which are t >= 0.

Can I give mathcad the information, that it calculate only with values t>0

Please look to the matcad file, where I have made also a lot of comments on page 4.

The pages before is normally not relevant for you.

Thanks a lot

Regards

Roger

[AlvaroDíaz · Accepted solution]

Please see attached.

Regards. Alvaro.

[Roschee]

Hello Alvaro,

I have openend your mathcad file and I can see that you have created an graph, but I don't see an curve.
Also the invlaplace

current_1(s):=CURRENT_1(s) invlaplace, s

ist colored in red.

Is it working at your home ?

I use mathcad 14

Regards

Roger

[RichardJ]

I use mathcad 14

which version of 14?

[Roschee]

Mathcad 14.0 M020 (14.0.2.5)

[RichardJ]

There have been lots of problems with Laplace transforms in MC14. I guess this is one where it's broken in M020, but they have since fixed it.

[AlvaroDíaz]

At work, in mc15, the image of the answer. There are a lot of problems with laplace and invlaplace with mupad.

Regards. Alvaro.

[Roschee]

Can I give mathcad some help ( t>=0 ), that he can calculate it.

Or can I split the function, that it would be easier to calculate it for

mathcad.

Regards

Roger