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Plot won't evaluate unless a calculated function explictly defined

Einhorn
Newbie

Plot won't evaluate unless a calculated function explictly defined

Hello,

Please see the attached MCAD worksheet.

The function alpha (t) has a variable alpha max that is previously defined. Alpha max carries units with it and those units appear correct. In the sheet I can only get the plot for omega to work by manually setting Alpha max to a value with the correct units (1/s^2).

I cannot figure out why the program is doing this. If anybody can assist that would be greatly appreciated!

Thank you,

Mike

10 REPLIES 10

Re: Plot won't evaluate unless a calculated function explictly defined

The symbolic solver doesn't like units. I suggest you tackle the problem as in the attached.

Alan

Re: Plot won't evaluate unless a calculated function explictly defined

Thanks Alan. I see. I can get it to run if I do those substitions. I can also get it to run if I make it dependent on T. I would like to not have to do this so I can see the explicit values of the evaluated function without the variables in them.

Re: Plot won't evaluate unless a calculated function explictly defined

Michael Einhorn wrote:

Thanks Alan. I see. I can get it to run if I do those substitions. I can also get it to run if I make it dependent on T. I would like to not have to do this so I can see the explicit values of the evaluated function without the variables in them.

I guess Wayne is using M15 (M010). Looks like you will have to upgrade to that if you want to see the explicit values all the time!

Alan

Re: Plot won't evaluate unless a calculated function explictly defined

Yes, I am using M010

Re: Plot won't evaluate unless a calculated function explictly defined

Am I missing something?
It works for me (M15)

tmp9.gif

Re: Plot won't evaluate unless a calculated function explictly defined

Hello Wayne,

I am running M14...I wonder if that is the issue?

Re: Plot won't evaluate unless a calculated function explictly defined

Interesting! This is what I get in M15 (F000):

Org.PNG

There is a small difference in the way the solution is expressed. My modified approach gives:

Mod.PNG

Looks like the only difference in the graph is due to the different range for t.

Alan

Re: Plot won't evaluate unless a calculated function explictly defined

I get the same, I just changed the range because the prior graph started at t=0. But I could plot -10 to 10 as well.

Attached sheet with active graph and a picture of the graph I get?

Re: Plot won't evaluate unless a calculated function explictly defined

Wayne Reid wrote:

I get the same, I just changed the range because the prior graph started at t=0. But I could plot -10 to 10 as well.

Attached sheet with active graph and a picture of the graph I get?

Your sheet gives the error in my version of M15 also. You must be using the updated version.

Alan

Re: Plot won't evaluate unless a calculated function explictly defined

All, I just installed M15 Date code M010 and that fixed the issue.


Thanks!

Mike

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