algorithms about primality in pari/gp

[aaa120]

I want to know several algorithms about primality in pari/gp.
the function name is “ispseudoprime”。
who can describe the algorithms which are used in ispseudoprime?
the more detailed the better! Is there anyone who can provide me
with the source code which are used in "ispseudoprime"?

Until now ,Which algorithm is the best to test a given number is
prime or not ?
As we know ,before you factorize a given number ,you must test
the given number is prime or not !

[jasonp]

Next time, try this before asking...

[Jens K Andersen]

If you have PARI/GP then just type "?ispseudoprime" to get:

ispseudoprime(x,{n}): true(1) if x is a strong pseudoprime, false(0) if not.
If n is 0 or omitted, use BPSW test, otherwise use strong Rabin-Miller test
for n randomly chosen bases.

PARI/GP is open source. The source simply calls another function depending on the second parameter:

long
ispseudoprime(GEN x, long flag)
{
if (flag == 0) return BSW_psp(x);
return millerrabin(x, flag);
}

[aaa120]

Originally Posted by Jens K Andersen

If you have PARI/GP then just type "?ispseudoprime" to get:

ispseudoprime(x,{n}): true(1) if x is a strong pseudoprime, false(0) if not.
If n is 0 or omitted, use BPSW test, otherwise use strong Rabin-Miller test
for n randomly chosen bases.

PARI/GP is open source. The source simply calls another function depending on the second parameter:

long
ispseudoprime(GEN x, long flag)
{
if (flag == 0) return BSW_psp(x);
return millerrabin(x, flag);
}

My native language is not English ,I cannot understand your words
very well.

[aaa120]

The source simply calls another function depending on the second parameter:

long
ispseudoprime(GEN x, long flag)
{
if (flag == 0) return BSW_psp(x);
return millerrabin(x, flag);
}[/quote]

I have installed pari/gp and type" long
ispseudoprime(GEN x, long flag)" in gp,but I cannot ger any source code !

[Jens K Andersen]

Originally Posted by aaa120

I have installed pari/gp and type" long
ispseudoprime(GEN x, long flag)" in gp,but I cannot ger any source code !

You can type a question mark before a function name to get a short description of that function. Typing "?ispseudoprime" outputs:

ispseudoprime(x,{n}): true(1) if x is a strong pseudoprime, false(0) if not.
If n is 0 or omitted, use BPSW test, otherwise use strong Rabin-Miller test
for n randomly chosen bases.

The source code is not output by a question mark. I downloaded the source code and manually inspected it to find this:

long
ispseudoprime(GEN x, long flag)
{
  if (flag == 0) return BSW_psp(x);
  return millerrabin(x, flag);
}