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Ocean/Calculator expressions and their units

MicheleA

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

Parents

  • Hi Andrew,

     thanks for the SKILL code! I will try and see how it works but since I am not SKILL-ed I decided to tackle the side topic first.

    I did add my small script as a measurement, as you suggested, and basically it works!. However, I have a couple of comments on this I'd like to share, namely:

     

    • the so created definition file does not get reloaded by ADE XL, neither when you tick/untick its plot enable box (as it happens for other expression that you can have available just by enabling them in the Outputs Setup pane and then going to the Results pane and click the curve button), nor if you re-run the simulation. I think this is quite dangerous. I actually had a bug in the first version of the script, which I solved, but it kept giving me errors until I found out that the software wasn't using the newer version on the disk...I use gedit as text editor and I also observed that the edit function doesn't necessarily lead to correct refresh of the file...But maybe I'm doing something unintended? The only sure fire way I've found to force a reload is to give the file path again...Tedious :)
    • As you pointed, I had to use axlAddOutputs() and axlOutputResult()...However I find the concept a little awkward, probably because I'm looking from the wrong perspective? The way I understood the workings of this is
      • start w/ axlAddOutputs() and create a list of labels
      • define my own expressions...and for this I also use "labels", like in vtank=VF(" /node")...vtank is a label, right?
      • finish w/ axlOutputResult() where I join my expressions with the list of labels given to axlAddOutputs()

    Now, this procedure looks like I have to come up with two names for everything I want to calculate AND to output so it is not exactly efficient in my view...Am I just doing it wrong?

     

    I look forward to testing your function and really thanks for your fast response!

    Regards,

    Michele 

Reply

  • Hi Andrew,

     thanks for the SKILL code! I will try and see how it works but since I am not SKILL-ed I decided to tackle the side topic first.

    I did add my small script as a measurement, as you suggested, and basically it works!. However, I have a couple of comments on this I'd like to share, namely:

     

    • the so created definition file does not get reloaded by ADE XL, neither when you tick/untick its plot enable box (as it happens for other expression that you can have available just by enabling them in the Outputs Setup pane and then going to the Results pane and click the curve button), nor if you re-run the simulation. I think this is quite dangerous. I actually had a bug in the first version of the script, which I solved, but it kept giving me errors until I found out that the software wasn't using the newer version on the disk...I use gedit as text editor and I also observed that the edit function doesn't necessarily lead to correct refresh of the file...But maybe I'm doing something unintended? The only sure fire way I've found to force a reload is to give the file path again...Tedious :)
    • As you pointed, I had to use axlAddOutputs() and axlOutputResult()...However I find the concept a little awkward, probably because I'm looking from the wrong perspective? The way I understood the workings of this is
      • start w/ axlAddOutputs() and create a list of labels
      • define my own expressions...and for this I also use "labels", like in vtank=VF(" /node")...vtank is a label, right?
      • finish w/ axlOutputResult() where I join my expressions with the list of labels given to axlAddOutputs()

    Now, this procedure looks like I have to come up with two names for everything I want to calculate AND to output so it is not exactly efficient in my view...Am I just doing it wrong?

     

    I look forward to testing your function and really thanks for your fast response!

    Regards,

    Michele 

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