Substitude variables on a array of equations...  Hewlett Packard
This is a discussion on Substitude variables on a array of equations...  Hewlett Packard ; Hi all!
I have a function that retuns me a array with two equations...
Something like this:
[x^2+y X^22y]
Is there any way that i can use to substitute X and Y by real numbers,
like;
x=2 and y=1
And ...

Substitude variables on a array of equations...
Hi all!
I have a function that retuns me a array with two equations...
Something like this:
[x^2+y X^22y]
Is there any way that i can use to substitute X and Y by real numbers,
like;
x=2 and y=1
And get an array with the responses:
[5 2]
Thanks a lot!!!

Re: Substitude variables on a array of equations...
I'm not a big expert but I would use two mechanisms (in RPN):
1) Give values to variabile (for aproximate result)
[X^2+Y X22Y] using Matrix Writer (remember quote ' to input algebric
construct)
2
'X'
STO
1
'Y'
STO
>NUM
3) Use symbolic substitutions (SUBST command in ALG menu)
[X^2+Y X22Y] using Matrix Writer
'X=2'
SUBST
'Y=1'
SUBST
EXPAND
There is a  (where) construct but I'm not very able in using it. Pheraps
some newsgroup "gurus" can help us.
MS

Re: Substitude variables on a array of equations...
On Apr 18, 10:12 am, Regis Daniel
wrote:
> Hi all!
>
> I have a function that retuns me a array with two equations...
> Something like this:
>
> [x^2+y X^22y]
>
> Is there any way that i can use to substitute X and Y by real numbers,
> like;
> x=2 and y=1
>
> And get an array with the responses:
> [5 2]
>
> Thanks a lot!!!
HI!
It's very simple.
Create an array with the matrix writer [white button  O (between N
and P)], then press [orange button O (between N and P] to create an
equation within the array, then press x^2+y, ENTER. Then repeat for
the next equation, then ENTER to place the array on the stack. Your
matrix should look like this:
[ 'x^2+y' 'x^22*y'] in level 1. Then start a new array (see above),
start equation writer within the array and enter x=2 Enter, eq writer,
y=1, ENTER ENTER.
The stack will now show (if things were done right):
2: ['x^2+y' 'x^22*y]
1: [x=2 y=1]
now press: orange4 (the ALG menu), NXT (to go to page two), press
SUBST, and voila! X and Y will be substituted with the appropriate
values. You will have to edit each element and press EVAL to reduce,
but minor point.
Please note: I assume you are using a 50g. If you don't have one, I
hope you will give serious consideration getting one.
I hope this helps!