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FloatApprox

approx. of rational number of the form M*10^E

Syntax
FloatApprox(X:RAT, RelErr:RAT):RAT

Description
This function computes an approximation of the form M*10^E to a rational number X and to within a maximum specified relative error. RelErr says indirectly how many decimal digits to include in the mantissa. Compare with MantissaAndExponent .

Example
/**/  FloatApprox(1/3, 10^(-2));
333/1000

/**/  FloatApprox(1000000/3, 10^(-2));
333000

/**/  FloatApprox(1/3, 10^(-9));
3333333333/10000000000

See Also