domain error

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Summary:

i tryed writing this program to generate large primes, but i get a domain error. I tried "running" the code line by line on a calculator page, but no error showed up. Can anyone help?

domain error

ProgrAnton 16 Dec 2014 19:00

so i am trying to generate big primes, but the randint() function only works for number up to 10^13.
This way i am trying to generate primes of, say 100 digits in a resenable time for encription.

this is the code

Define findprime(dig)=
Func
loop
  dig:=round(((dig)/(10)),0)
  prime:=""
  For a,1,dig
    prime:=prime&string(randInt(10^(9),10^(10)-1))
  EndFor
  prime:=expr(prime)
  If isPrime(prime)=true Then
    Return prime
    Goto end
  EndIf
endloop
Lbl end
EndFunc

and this is the error i get

Domain error

An argument must be in a specified domain.

Re: domain error

Timtech 26 Dec 2014 12:27

68k:isprime

"TI-92 Plus and TI-89 family start the same way, except that they stop this trial division after trial divisor 1021". Although I have little experience with the NSpire, it would seem reasonable to me that if there is a limit of 10^13 for randint then there very well could be a similar limit for isPrime.