HP49g+ plotting multiple functions

[MathAssassin]

How do I plot multiple functions simultaneously?

I would like to make two plots at once. For example: in polar r = cos theta, r = sin theta. Or in cartesian y = x and y = 2x. For example, to find intersections.

I searched the user's manual, user's guide, and the advanced user's guide to the best of my abilities (I am legally blind and must use a video magnifier). If one can help me and tell me which page in the documentation I can refer to, I would be grateful.

[Brad Barton]

Plot the first equation, then go back to the equation entry window and enter the second equation. Plot the 2nd one without erasing the first. That should do it.

[MathAssassin]

Thank you. That worked.

Another question if you don't mind. I am following this guide to convert between polar and rectangular coordinates. However, when attempting to enter a polar coordinate to the stack, I am not able to enter an angle in radians in the form of an expression of pi.

For example, in MODE I have Radians angle measurement and Polar for coordinate system. In the stack I attempt to input () 1 ALPHA Right-Shift 6 Left-Shift SPC
to try to enter (1,pi) ... but I get "invalid syntax". I tried to use '' as well to no avail.

[Joe Horn]

(08-14-2014 03:18 PM)MathAssassin Wrote:  Another question if you don't mind. I am following this guide to convert between polar and rectangular coordinates. However, when attempting to enter a polar coordinate to the stack, I am not able to enter an angle in radians in the form of an expression of pi.

For example, in MODE I have Radians angle measurement and Polar for coordinate system. In the stack I attempt to input () 1 ALPHA Right-Shift 6 Left-Shift SPC
to try to enter (1,pi) ... but I get "invalid syntax". I tried to use '' as well to no avail.

Can't do that (as you discovered). The angle symbol is only a direct numeric entry method; it can't be mixed with calculations. It's like trying to enter 1.23 EEX (2^4) to get 1.23E16. That doesn't work because EEX only allows digits, not calculations. Same with the angle symbol while entering polar angles.

Suggestion #1: Leave your calculator in polar display mode, but create the point using the ->V2 function (in the MTH VECTR menu) instead of the angle symbol. Make sure flag -19 is set (that forces the ->V2 function to create a complex number instead of a vector). Example:

To create the polar point (7.8 angle pi/6), type 7.8 pi 6 / ->V2.

To see the angle in terms of pi, use ARG ->Qpi.

Suggestion #2: Use degrees. They're neater.

[dizzy]

(08-14-2014 12:54 AM)MathAssassin Wrote:  How do I plot multiple functions simultaneously?

I would like to make two plots at once. For example: in polar r = cos theta, r = sin theta. Or in cartesian y = x and y = 2x. For example, to find intersections.

I searched the user's manual, user's guide, and the advanced user's guide to the best of my abilities (I am legally blind and must use a video magnifier). If one can help me and tell me which page in the documentation I can refer to, I would be grateful.

You can supply a list of functions to the plotter, and each will be plotted in turn. The equation editor can't edit lists though, so it's easier to do this:

{'x', '2*x'} STEQ

... and then revisit the "2D/3D" screen.