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Logarithmic-Plot: semilogx() loglog() - Printable Version

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Logarithmic-Plot: semilogx() loglog() - lesterhedrick - 02-05-2014 07:28 PM

Hello there!

I would very much like to be able to plot graphs (transferfunctions) with doublelogarithmic or semilogarithmic axes (with matching Ticks, meaning I know about the "Parametric Plot"-App Wink )

Is there any way to do this right now? Do I/we have to wait for an HP-Update or (write) a custom-plot-function?
I hope iam not the only one missing/searching this function Wink

Cheers and thanks for any replies


RE: Logarithmic-Plot: semilogx() loglog() - Harold A Climer - 02-06-2014 04:04 PM

You can always transform your data as a workaround and use a linear graph, until the PRIME folks add this to the OS.


RE: Logarithmic-Plot: semilogx() loglog() - Francis Mathews - 03-26-2017 06:25 PM

You can write your formula in terms of 10^x. The plot will be in terms of "decades". For instance, when plotting the amplitude in decibels of a function like F(s)=10s/((s+100)(s+1000), where s = i.x (i is the imaginary unit, and x is the angular frequency in radians per second), something that led me to this thread, I entered in the HP-PRIME: F1(x) = 20*log(|10*((0,10^x))/(((0,10^x)+100)*((0,10^x)+1000))|), it is much easier to read on the HP-PRIME screen. The plot versus x, which is actually the common logarithm of your original variable is just what I wanted.
To see the plot, I went to [shift] setup/plot and entered as the horizontal range for the plot x between -2 and 5, and y between -100 and -50. I have included a screen shot or three of the process below, click on it. Good luck on your journey!