Is There a Way to Rationalize a Decimal in Pari/GP?

[Rick Regan <exploringbinary@gmail.com>]

I'm looking for an automated way to turn a decimal value into a
fraction in the PARI/GP calculator (gp). For example, I want to turn
0.759765625 into 389/512. I know I can do this manually by typing in
'759765625/10^9', but I'd like an easier way, like
'rationalize(0.759765625);' would work in Maxima.

If it can't do this directly, maybe there's a function to count the
number of decimal places? Then I could raise 10 to the result of that
function. (The function would have to count leading decimal places of
0s to be useful.)

Thanks.

Rick Regan

-- 
“There are 10 types of people ... those who understand binary and
those who don't” -- http://www.exploringbinary.com