Arrays in tiBasic?

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Summary:

I don't know how to make arrays in tiBasic

Arrays in tiBasic?

noob69 31 Oct 2008 03:19

I want to make a single dimensional array of integers for a prime generating program that I would like to create. My calculator is a ti84. If you could please explain to me how to declare and access arrays in tibasic. Thanks for helping. :)

In c# it would look like this:
int[] primes;
primes = new int[1000]
primes[0] = 2;

Re: Arrays in tiBasic?

Edward H 31 Oct 2008 03:36

What you're looking for is lists.

You would do that bit of C# code like this in TIBasic:

:SetUpEditor PRMS
:1000→dim(∟PRMS
:2→∟PRMS(1

However, keep in mind several differences between TIBasic and more sophisticated languages like C#. First, you can't declare integer lists. There is only one kind of list: floating point. So a 1000-element list would take up an obscene amount of memory on a calculator. Also, the list index starts at 1, not 0. There is also no undefined or null element: only numbers can go in lists. Also, the size of a list can change; so there's no need to initialize the list with 1000 elements (unless you were doing something like a Sieve of Erasasdfjkl). You can simply store the next value to the next unused list index: 3→∟PRMS(2

Anyway, welcome to this site! If you'd like to learn more about TI-Basic, just ask! And of course, you can always look through the wiki, which has many useful resources for beginners. :D

Last edited on 31 Oct 2008 03:36 by Edward H Show more

Re: Arrays in tiBasic?

thornahawk 31 Oct 2008 15:23

You do know about the "999 elements" limitation for lists?

I had a nice Eratosthenes sieve a while back…

PROGRAM:SIEVE
Prompt N
int(N/2)→M
M→dim(∟T)
Fill(1,∟T)
2→P:3→K
While K²≤N
For(J,P+K,M,K)
0→∟T(J)
End
Repeat ∟T(P)
P+1→P
End
2P–1→K
End
{2}→P:2→J
For(P,2,M)
∟T(P)→H
If H
2P–1→∟P(J)
J+H→J
End
DelVar ∟T
∟P

which returns your list of primes in ∟P . You might find it useful.

thornahawk