HP 50g function plotting

[Cristi Neagu]

Hello,

Just joined to ask a specific question, because i can't seem to find an answer for it.

Say i have an arithmetic relation either on the stack or stored in a variable. Something like

Code:

'2X^3'

How can i plot it? As far as i can tell, going into the 2D/3D or the Y= "windows" i can only start writing a new one, but there seems to be no way for me to use an already defined function. Is there any easy way to plot an already defined function?

I can see that in the Y= window i can use an equation defined in the current folder, but not a simple function. I can also see that i can store that relation in the Eq variable and it will then show up. Is that the correct way of doing it? Storing functions in the Eq variable and then plotting? Seems more of a hack than anything else...

Thank you.

[franz.b]

User manual, chapter 12.

[Cristi Neagu]

(05-11-2020 02:29 PM)franz.b Wrote:  User manual, chapter 12.

Thank you for the reply.

Chapter 12 of the user manual refers to partial derivatives and multiple integrals, so i assume you meant chapter 12 of the user guide. I have already gone over that chapter and it mostly deals with writing equations directly in the "Y=" window or the "2D/3D" window. The only other input method i could find in that chapter is by using the "Choose" menu in the "Y=" window, but that does not work with equations on the stack or with algebraic objects stored in a variable. It only works with defined equations.

So the question remains. If i have "2X^3" on the stack, can i not input it in either the "Y=" or the "2D/3D" windows? Is the only way to do that by defining it as an equation?

Thank you.

[Carsen]

5 ways that I would use to accomplish this.

1. Use the PLOT command. Press SYMB -> GRAPH -> PLOT.
2. Store it in EQ, just like you said earlier.
3. When in the 2D/3D input form, press the HIST key, then ECHO, then ENTER. Then ENTER/OK.
4. Write a small program to take an equation & immediately plot it with default zoom settings.
5. PLOT soft menu. Accessed by: 81 MENU. Pretty cumbersome though. Useful for plotting commands in programming.

Useful tip in general
----------------------
Read the HP 48G/GX user's manuals. You'll find useful information for your 50g. Like how pressing STO in the PICTURE environment puts a GROB of the graph in the stack.

[Cristi Neagu]

(05-11-2020 06:18 PM)Carsen Wrote:  5 ways that I would use to accomplish this.

1. Use the PLOT command. Press SYMB -> GRAPH -> PLOT.
2. Store it in EQ, just like you said earlier.
3. When in the 2D/3D input form, press the HIST key, then ECHO, then ENTER. Then ENTER/OK.
4. Write a small program to take an equation & immediately plot it with default zoom settings.
5. PLOT soft menu. Accessed by: 81 MENU. Pretty cumbersome though. Useful for plotting commands in programming.

Useful tip in general
----------------------
Read the HP 48G/GX user's manuals. You'll find useful information for your 50g. Like how pressing STO in the PICTURE environment puts a GROB of the graph in the stack.

Thank you for the reply.

It's a bit weird that you can't just take an algebraic expression off the stack and just plot it, but i assume it has to do with the way the 6 function key apps (is that even the right word for them?) have to work together. In any case, that pretty much answers the question. Thank you.

[BruceH]

(05-10-2020 05:07 PM)Cristi Neagu Wrote:  Hello,

Just joined to ask a specific question, because i can't seem to find an answer for it.

Say i have an arithmetic relation either on the stack or stored in a variable. Something like

Code:

'2X^3'

How can i plot it? As far as i can tell, going into the 2D/3D or the Y= "windows" i can only start writing a new one, but there seems to be no way for me to use an already defined function. Is there any easy way to plot an already defined function?

I can see that in the Y= window i can use an equation defined in the current folder, but not a simple function. I can also see that i can store that relation in the Eq variable and it will then show up. Is that the correct way of doing it? Storing functions in the Eq variable and then plotting? Seems more of a hack than anything else...

Thank you.

In ALG mode, from a freshly reset calculator:

1. Type in '2X^3' and press Enter so that it is in the history level one
2. Press Y=
3. Press ADD
4. Press HIST
5. Press ECHO
6. Press Enter
7. Press DRAW
   

Same for RPN mode, except you have to hold right-shift and press Y= otherwise it tries to do whatever is right-shift assigned to the F1 menu position.

[Joe Horn]

(05-11-2020 06:27 PM)Cristi Neagu Wrote:  

(05-11-2020 06:18 PM)Carsen Wrote:  ...
5. PLOT soft menu. Accessed by: 81 MENU. Pretty cumbersome though. Useful for plotting commands in programming. ...

Thank you for the reply.

It's a bit weird that you can't just take an algebraic expression off the stack and just plot it...

Did you try Carsen's 81 MENU suggestion? I think it's exactly what you're looking for. If you assign << 81 MENU >> to a key, then it'll be available in one keystroke. Once menu 81 is showing, you have STEQ available right there (left-shift EQ) as well as ERASE (optional, to clear any previous plot), DRAX (optional, to draw the X & Y axes), and DRAW (creates the graph).

For your example, with '2*X^3' on the stack, just press STEQ DRAW to create the graph you desire. (Include ERASE and DRAX as desired). There's even a handy PPAR soft key in menu 81 which lets you check and set the graphing parameters. And a PTYPE soft key to set the plot type. Menu 81 is your friend.

[Cristi Neagu]

(05-12-2020 03:25 AM)Joe Horn Wrote:  

(05-11-2020 06:27 PM)Cristi Neagu Wrote:  Thank you for the reply.

It's a bit weird that you can't just take an algebraic expression off the stack and just plot it...

Did you try Carsen's 81 MENU suggestion? I think it's exactly what you're looking for. If you assign << 81 MENU >> to a key, then it'll be available in one keystroke. Once menu 81 is showing, you have STEQ available right there (left-shift EQ) as well as ERASE (optional, to clear any previous plot), DRAX (optional, to draw the X & Y axes), and DRAW (creates the graph).

For your example, with '2*X^3' on the stack, just press STEQ DRAW to create the graph you desire. (Include ERASE and DRAX as desired). There's even a handy PPAR soft key in menu 81 which lets you check and set the graphing parameters. And a PTYPE soft key to set the plot type. Menu 81 is your friend.

Like i said in my reply to Carsen, he did answer my question and his solutions obviously work. I was referring to the ability to do it "out of the box". It was just a remark, not a complaint. I could have been a bit clearer, to be honest.

Thank you.

[BruceH]

(05-11-2020 06:27 PM)Cristi Neagu Wrote:  It's a bit weird that you can't just take an algebraic expression off the stack and just plot it

Put your expression on the stack, right-shift CAT, scroll down to PLOT and press OK.

[Joe Horn]

(05-12-2020 12:27 PM)BruceH Wrote:  

(05-11-2020 06:27 PM)Cristi Neagu Wrote:  It's a bit weird that you can't just take an algebraic expression off the stack and just plot it

Put your expression on the stack, right-shift CAT, scroll down to PLOT and press OK.

Slightly more keystroke efficient: SYMB GRAPH PLOT, or CALC GRAPH PLOT.