unable to plot UTPN

[stroran]

Hi,

Plotting the function

<< -> X << 0 1 X LN UTPN >> >>

leads to an error message: "UTPN Error: Bad Argument Type". Any suggestions as to why this is happening?

When I store the function above in a variable V and enter it in the command line, it evaluates to a number just fine, e.g., V(1) EVAL leads to 0.5 as expected. But when I use V(X) as the function to be plotted it complains as described above.

This issue is related to having the function LN(X) as the argument to UTPN. Do I need an extra step to make sure LN(X) evaluates to whatever datatype UTPN takes?

Thank you very much for your time.

[Tim Wessman]

If you are in approximate mode, then you should be fine. If not, add in a ->NUM right before the UTPN.

TW

[stroran]

Thanks Tim.

Unfortunately, I can't still get it to plot even with ->NUM. The funny thing is that

<< -> X << 0 1 X COS ->NUM UTPN >> >>
or
<< -> X << 0 1 X EXP ->NUM UTPN >> >>

plot as expected. However,

<< -> X << 0 1 X LN ->NUM UTPN >> >>
or
<< -> X << 0 1 X LOG ->NUM UTPN >> >>

refuse to plot giving "UTPN Error: Bad Argument Type". Do log functions need to be treated differently? I have an HP50g.

[Kiyoshi Akima]

What's your plot range? Can x be negative? Then ln(x) is complex, and UTPN doesn't like complex numbers.