50g

After entering an equation with the equation writer, with one variable
such a 'x', how do you evaluate 'x' for the equation?
It seems like using the equation writer might be easier than
programming. For programming, do you start with << >> button, and
finish with the left arrow prg button?
My old HP15c was simple to program; an example would be:
g prg
f prgm
f LBL A
STO 0
SIN
1/x
STO1
RCL 0
g x^2
3
/
RCL 1
X
g RTN
g PRG

if x = 3, then f(x) = 21.26 (using radians)
Could this be programmed easier with the HP50G?
Thanks

I can't follow the code you gave, never used a 15c.
But if you want to evaluate a function for values you
enter individually, one of the many ways is to
"define" a softkey for it. Say the function is
f(x)=sin(1/x). Enter it as 'f(x)=sin(1/x)' by pressing
the '' key first then typing in the function followed
by enter. Then press the def key (left shift 2 on the
49g, probably the same on the 50g) and you should see
a soft key labeled f. Now to evaluate the function at
3 just press 3 and then the f soft key.

To enter a program press the <<>> key and enter the
program between those delimiters. Press enter and the
program will be on the stack which you can then store
under a variable name of your choice. You'll really
need to RTFM to learn programming.


--- alanthegringo <alanthegringo@...> wrote:

> After entering an equation with the equation writer,
> with one variable
> such a 'x', how do you evaluate 'x' for the
> equation?
> It seems like using the equation writer might be
> easier than
> programming. For programming, do you start with <<
> >> button, and
> finish with the left arrow prg button?
> My old HP15c was simple to program; an example
> would be:
> g prg
> f prgm
> f LBL A
> STO 0
> SIN
> 1/x
> STO1
> RCL 0
> g x^2
> 3
> /
> RCL 1
> X
> g RTN
> g PRG
>
> if x = 3, then f(x) = 21.26 (using radians)
> Could this be programmed easier with the HP50G?
> Thanks
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>
>

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--- Don Hart <ddhart1@...> wrote:

> I can't follow the code you gave, never used a 15c.
> But if you want to evaluate a function for values
> you
> enter individually, one of the many ways is to
> "define" a softkey for it. Say the function is
> f(x)=sin(1/x). Enter it as 'f(x)=sin(1/x)' by
> pressing
> the '' key first then typing in the function
> followed
> by enter. Then press the def key (left shift 2 on
> the
> 49g, probably the same on the 50g) and you should
> see
> a soft key labeled f. Now to evaluate the function
> at
> 3 just press 3 and then the f soft key.
>...

The soft key with the label of f, sorry.


____________________________________________________________________________________
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Alan   text message attached below  --  try it    Ed

alanthegringo <alanthegringo@...> wrote:

After entering an equation with the equation writer, with one variable
such a 'x', how do you evaluate 'x' for the equation?
It seems like using the equation writer might be easier than
programming. For programming, do you start with << >> button, and
finish with the left arrow prg button?
My old HP15c was simple to program; an example would be:
g prg
f prgm
f LBL A
STO 0
SIN
1/x
STO1
RCL 0
g x^2
3
/
RCL 1
X
g RTN
g PRG

if x = 3, then f(x) = 21.26 (using radians)
Could this be programmed easier with the HP50G?
Thanks

between 0000-00-00 and 9999-99-99  

--- In 50g@yahoogroups.com, "alanthegringo" <alanthegringo@...> wrote:

>
> After entering an equation with the equation writer, with one

variable

> such a 'x', how do you evaluate 'x' for the equation?
> It seems like using the equation writer might be easier than
> programming. For programming, do you start with << >> button, and
> finish with the left arrow prg button?
> My old HP15c was simple to program; an example would be:
> g prg
> f prgm
> f LBL A
> STO 0
> SIN
> 1/x
> STO1
> RCL 0
> g x^2
> 3
> /
> RCL 1
> X
> g RTN
> g PRG
>
> if x = 3, then f(x) = 21.26 (using radians)
> Could this be programmed easier with the HP50G?
> Thanks
>

Here is one of the possible equivalent in HP50:

<< -> a << a SIN INV a SQ 3 / * >> >>

where "<<" is the double caret program delimiter, and "->" is the
little assignement arrow.

Save that program by entering a variable name on the stack,
say "Demo", and pressing STO>. This will add a soft key labelled
Demo, and using the program is only a matter of entering the "x"
walue you want to use (actually, it is called "a" in the program...)
and pressing the soft button corresponding to Demo.

One thing to remember is that the HP50 does not use explicit memory
reference (STO 1; RCL 0) to access data; it does so symbolically,
hence the assignement to "a" at the beginning of the program, which
takes whatever value is on the stack and puts it into "a". From then
on, anytime it sees "a", the calculator will bring back the current
value of "a".

In your program, you are saving the result of 1/SIN(x) into memory 1
(STO 1); in the case of the program above, I just leave that value on
the stack, something you could also have done with your HP15; but if
retaining that value is significant in a more elaborate program, it
could have been put in another local variable by adding the statements

-> b

and then using "b" instead of "RCL 1". Just remember that having a
value assigned with the -> function calls for using anotehr layer
of "<< >>" delimiter, as the local variable applies to that sub-
function.



CBVG

--- In 50g@yahoogroups.com, "vincentgoudreault" <vgoudreault@...> wrote:

>
>
>
> Here is one of the possible equivalent in HP50:
>
> << -> a << a SIN INV a SQ 3 / * >> >>
>

One last thing to remember: since this program uses local variables,
the value of "a" as it stands is not retained at the conclusion of the
program. That is what the "<< >>" delimit: the scope of that variable.


CBVG

 

Hello Alan, In order to evaluate that function you have two options (I suppose you are in RPN):

1. You can use DEF.

'FUNC(X)=SQ(X)/(3*SIN(X))' [ENTER] [leftShift] DEF

DEF is associated to key [2]

to run press [3] [VAR] FUNC and you get 21.258502...

2. If you want, you can evaluate the function as a program, you don't need variables for a small function, just manipulate the stack.

«  DUP SQ SWAP SIN / 3 /  »  'FUNC' [STO]

again, to run press [3] [VAR] FUNC and you get 21.258502...

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 To delete a variable put the name of the variable enclosed with single quotes like 'FUNC' press [ENTER] and then [TOOL] and PURGE (associated to [F6]) if you press [VAR] it is not there anymore).  If you realize that you didn't want to delete the variable, right after you execute the command PURGE, you still can recover it with this procedure:

• firsrt, press [leftShift] ANS (associated with [ENTER]) and you get the object that was stored in the variable in level 2: and the variable name in level 1:
• second, at this point just press [STO], your variable is back in the directory.

Don't worry too much about using variable names predefined for special purposes, its very unlikely. I try not to work in the HOME directory, create your own directory.

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