D.14.7 mpfr functions with miscellaneous calling conventions

Some functions listed below don't conform to any of the previously mentioned calling conventions.

eq

This is a ternary operator taking a triple (prec,(x,y)), where prec is a natural number and x and y are mpfr numbers. It returns a result of (nil,nil) (i.e., true) if the numbers agree up to the specified precision measured in bits, and returns nil otherwise.¹

urandomb

This function takes a natural number specifying a precision and returns a uniformly distributed pseudo-random number of that precision between 0 and 1.

prec

This function takes an mpfr number and returns a natural number as a result, which is the precision of the argument in bits.

sin_cos

This function takes an mpfr number z as an argument and returns a pair of mpfr numbers (x,y) as a result, where x is the sine of z and y is the cosine. The precisions of the results are the same as the precision of the argument.