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  3. Ocean/Calculator expressions and their units

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Ocean/Calculator expressions and their units

MicheleA
MicheleA over 13 years ago

Hi all,

I know it's not advised to put more than one questions per post, however I hope I'll structure this such that there won't be no confusion.

Main Topic

I am defining some expressions I would like to assess in my designs. To this end, I use the calculator in conjunction with some "ocean" script...Actually I just write expressions and define variables on a plain text file, but the idea is to expand on that with plotting functions and maybe output to file.

So let's say I have an AC sim. I then define some curves as follows:

 

twoPi = 44.0/7.0

vtank = VF("/tank_pos")-VF("/tank_neg")

itank = IF("/Vgen/MINUS")

icap = IF("/Cprobe/PLUS")

icapfix = IF("/Cfprobe/PLUS")

iind = IF("/Lprobe/PLUS")

runfreq = xval(vtank)

Ytank = itank/vtank

Zcap = vtank/icap

Zcapfix = vtank/icapfix

Zind = vtank/iind

cap = 1/(-twoPi*runfreq*imag(Zcap))

 

Now, it all works good if I copy/paste these definitions in the CIW, then ask --> plot(cap)

The issue I have with this is that now the Y-axis shows "freq" units...

cap value in femtohertz?

I observed that runfreq, defined as xval, is still correct. But if I do 1/runfreq, what I get is something with units of 1/(1/Hz), instead of s.

So probably here's where it loses it. Anyways, I see two possibilities here:

 

  1. I am doing it wrong
  2. I am doing it right

 

If 1 holds, then what's the right approach for something like this?

If 2 holds, do I have a way of "forcing" units onto expressions?

--------------------------------------------------------------------------------------------- END ----------------------------------------------------------------------------------------- 

Side Topic

 I find it more comfortable to write my expressions in the text editor rather than inputting them in the output definition box of ADE or ADE-XL. Is there a way of having the environment read my definitions as a file, and then just output the final expressions? In the (simple) case at hand, I would have defined all expressions as above, and plot them either from the CIW or directly from the file...

 

Thanks for your help!!

 Michele

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  • MicheleA
    MicheleA over 13 years ago

    Hi Andrew,

     I think you were paying attention, the main thing was about the measurement units.

    I tended to ignore that little "freq" myself, in the beginning, and turned to it only when the other issue was solved.

    I tried however to use drSetWaveformYVec but it says "error eval: undefined function" both if I use the CIW and writing it on the OCEAN script...

    I will submit the test case I posted at beginning to the customer support later next week, I guess :)

     Michele

     

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  • MicheleA
    MicheleA over 13 years ago

    Hi Andrew,

     I think you were paying attention, the main thing was about the measurement units.

    I tended to ignore that little "freq" myself, in the beginning, and turned to it only when the other issue was solved.

    I tried however to use drSetWaveformYVec but it says "error eval: undefined function" both if I use the CIW and writing it on the OCEAN script...

    I will submit the test case I posted at beginning to the customer support later next week, I guess :)

     Michele

     

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