Average Error: 0.1 → 0.1
Time: 3.2s
Precision: binary64
\[\frac{{q}^{\left(n + 1\right)} - 1}{q - 1}\]
↓
\[\frac{{q}^{\left(n + 1\right)} - 1}{q - 1}\]
\frac{{q}^{\left(n + 1\right)} - 1}{q - 1}
↓
\frac{{q}^{\left(n + 1\right)} - 1}{q - 1}
double code(double q, double n) {
	return ((double) (((double) (((double) pow(q, ((double) (n + 1.0)))) - 1.0)) / ((double) (q - 1.0))));
}
↓
double code(double q, double n) {
	return ((double) (((double) (((double) pow(q, ((double) (n + 1.0)))) - 1.0)) / ((double) (q - 1.0))));
}

Error

Bits error versus q

Bits error versus n

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 0.1

    \[\frac{{q}^{\left(n + 1\right)} - 1}{q - 1}\]

  2. Final simplification0.1

    \[\leadsto \frac{{q}^{\left(n + 1\right)} - 1}{q - 1}\]

Reproduce

herbie shell --seed 2020152 
(FPCore (q n)
  :name "(/ (- (pow q (+ n 1)) 1) (- q 1))"
  :precision binary64
  (/ (- (pow q (+ n 1.0)) 1.0) (- q 1.0)))