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Pulse function using Heaviside Step Function

Cornel
18-Opal

Pulse function using Heaviside Step Function

Hi,

How can I make this pulse like function in more compact way but still following this variant from below?

Cornel_0-1717487481144.png

Cornel_1-1717487492107.png

1 ACCEPTED SOLUTION

Accepted Solutions
Werner_E
24-Ruby V
(To:Cornel)

Looks like "laplace" can't deal with "mod", floor" and similar functions and so it can't give you a result for the piecewise and periodic function.

Werner_E_0-1717500610032.png

 

"laplace" can deal with a finite number of pulses, but even then it can't deal with the number of pulses being a variable and not a constant.

Werner_E_1-1717500786669.png

 

I guess that unless PTC implements some kind of rect(t) or SquareWave(t) function and tells the symbolics its laplace transform, we can't talk Prime into returning the result

Werner_E_0-1717501906874.png

which you may expect for your square wave.

-> LaplaceTransform (1/2*SquareWave(t/4)+1/2) - Wolfram|Alpha

-> [Solved] The Laplace transform of the causal periodic square wave of

-> integration - Laplace transform of a square wave function - Mathematics Stack Exchange

View solution in original post

11 REPLIES 11

Something like this?

Steps.png

 

Alan

Hm, its a good variant also your variant. Idea is with the above variant we can do:

1. Laplace:

Cornel_0-1717488845317.png

Cornel_1-1717488854203.png

Cornel_2-1717488884057.png

 

 

2. Then I will want to extend (if possible) to such waveforms, but still using heaviside step function (and also those waveforms needs to have laplace transform counterpart:

Cornel_3-1717488940860.png

 

I do not know how my variant could look like, maybe something like this:

Cornel_5-1717489191469.png

or maybe splitted in 2 parts, do not know:

Cornel_0-1717489652893.png

 

Unfortunately, I only have the Express version of Prime, in which there are no symbolics (hence no Laplace), so I'm unable to help you further, I'm afraid.

 

Alan 

Werner_E
24-Ruby V
(To:Cornel)

Looks like "laplace" can't deal with "mod", floor" and similar functions and so it can't give you a result for the piecewise and periodic function.

Werner_E_0-1717500610032.png

 

"laplace" can deal with a finite number of pulses, but even then it can't deal with the number of pulses being a variable and not a constant.

Werner_E_1-1717500786669.png

 

I guess that unless PTC implements some kind of rect(t) or SquareWave(t) function and tells the symbolics its laplace transform, we can't talk Prime into returning the result

Werner_E_0-1717501906874.png

which you may expect for your square wave.

-> LaplaceTransform (1/2*SquareWave(t/4)+1/2) - Wolfram|Alpha

-> [Solved] The Laplace transform of the causal periodic square wave of

-> integration - Laplace transform of a square wave function - Mathematics Stack Exchange

Ok, its good also like this with finite number at this moment :

Cornel_0-1717502197815.png


Now, how to make something like above f(t,n) for these kind of waveforms but using only heaviside step function:

Cornel_1-1717502255835.png

 

Werner_E
24-Ruby V
(To:Cornel)


Now, how to make something like above f(t,n) for these kind of waveforms but using only heaviside step function:

Maybe that way:

Werner_E_0-1717506374694.png

 

There is this ramp function:

Cornel_0-1717509477812.png

Cornel_1-1717509496990.png

 

But this function cannot be laplace transform evaluated:

Cornel_2-1717509506084.png

 

I am wondering if this ramp function can be made in another way and in such a way that laplace transform could be caluculated for it?


EDIT: ok, I found how to do it

Cornel_0-1717509971504.png

Werner_E
24-Ruby V
(To:Cornel)

Laplace assumes f(t)=0 for t<0 anyway, so you could achieve the result easier with

Werner_E_0-1717511787201.png

But your picture (red plot)  doesn't show an infinite ramp but rather a triangle impulse ...

Werner_E_1-1717511842257.png

 

How to make f2(t) to have more numbers of triangles?

Werner_E
24-Ruby V
(To:Cornel)


@Cornel wrote:

How to make f2(t) to have more numbers of triangles?


Use the function I posted here
Solved: Re: Pulse function using Heaviside Step Function

with T/2 as second argument (see the second, blue plot).

 

Werner_E_0-1717513664744.png

 

ttokoro
20-Turquoise
(To:Cornel)

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