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Plot new curve basis a function of Y

Posted: Tue May 30, 2006 5:37 pm
by Greg
First off, this is a great program!

I thought my question would fall under a scaling function but I struck out in my search for an answer. I am probably not looking in the right area of the program.

Here is my example, I have velocity (Y) plotted versus time (X). I want to plot another curve on the same graph for flow on the Y axis versus time (X) using a linear equation with velocity as a variable, for this system the equation is; flow = 92.5(.7+velocity/428*.3)

The help menu is great but "somehow I got stuck" (older Warren Zevon tune)

Thanks for the help!

Greg Scott, PE
South Portland, ME

Posted: Tue May 30, 2006 6:55 pm
by jsc
Greg,

It looks like "Generate> Y=Poly(Y)" should work if you turn your equation into y=C0+C1*Y+C2*Y^2...etc.

Posted: Wed May 31, 2006 6:07 am
by Greg
I'll give that a try. Thanks for the help

Posted: Wed May 31, 2006 9:34 am
by DPlotAdmin
Jon,
Thanks for the assist.

Greg,
In addition to Jon's solution you can also make a copy of your curve (Edit>Copy>Data Values; Edit>Paste), then use Edit>Operate on Y with

Y=92.5*(0.7+Y/428*0.3)

Posted: Wed May 31, 2006 10:59 am
by Greg
Jon & David,

I will try both ways.

Thanks again!

Greg