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Cleaned up + rustfmt'ed

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This commit is contained in:
Rahul Butani
2018-07-23 02:54:53 -05:00
committed by Alex Crichton
parent 5dddb9b523
commit b814861c6d
1 changed files with 44 additions and 41 deletions
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src/math/pow.rs
+44 -41
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@@ -409,24 +409,14 @@ pub fn pow(x: f64, y: f64) -> f64 {
return s * z;
}
/// Special cases:
/// 20. (anything) ** 1 is (anything)
/// 21. (anything) ** -1 is 1/(anything)
/// 22. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
/// 23. (-anything except 0 and inf) ** (non-integer) is NAN
#[cfg(test)]
mod tests {
// #[macro_use]
extern crate std;
use self::std::f64::consts::{E, PI};
use self::std::f64::{EPSILON, INFINITY, MAX, MIN, MIN_POSITIVE, NAN, NEG_INFINITY};
use super::pow;
// const TESTCASES: &[f64] = &[1.0, 0.0, PI, -PI, E, -E, MIN, MAX, MIN_POSITIVE, NAN, INFINITY, NEG_INFINITY];
const POS_ZERO: &[f64] = &[0.0];
const NEG_ZERO: &[f64] = &[-0.0];
const POS_ONE: &[f64] = &[1.0];
@@ -440,21 +430,43 @@ mod tests {
const POS_ODDS: &[f64] = &[3.0, 7.0];
const NEG_ODDS: &[f64] = &[-7.0, -3.0];
const NANS: &[f64] = &[NAN];
// const EDGES: &[f64] = &[MIN, MAX, MIN_POSITIVE, EPSILON];
const POS_INF: &[f64] = &[INFINITY];
const NEG_INF: &[f64] = &[NEG_INFINITY];
const ALL: &[&[f64]] = &[
POS_ZERO, NEG_ZERO, NANS, NEG_SMALL_FLOATS, POS_SMALL_FLOATS, NEG_FLOATS, POS_FLOATS, NEG_EVENS, POS_EVENS, NEG_ODDS, POS_ODDS,
NEG_INF, POS_INF, NEG_ONE, POS_ONE,
POS_ZERO,
NEG_ZERO,
NANS,
NEG_SMALL_FLOATS,
POS_SMALL_FLOATS,
NEG_FLOATS,
POS_FLOATS,
NEG_EVENS,
POS_EVENS,
NEG_ODDS,
POS_ODDS,
NEG_INF,
POS_INF,
NEG_ONE,
POS_ONE,
];
const POS: &[&[f64]] = &[POS_ZERO, POS_ODDS, POS_ONE, POS_FLOATS, POS_EVENS, POS_INF];
const NEG: &[&[f64]] = &[NEG_ZERO, NEG_ODDS, NEG_ONE, NEG_FLOATS, NEG_EVENS, NEG_INF];
fn pow_test(base: f64, exponent: f64, expected: f64) {
let res = pow(base, exponent);
assert!(if expected.is_nan() {res.is_nan()} else {pow(base, exponent) == expected},
"{} ** {} was {} instead of {}", base, exponent, res, expected);
assert!(
if expected.is_nan() {
res.is_nan()
} else {
pow(base, exponent) == expected
},
"{} ** {} was {} instead of {}",
base,
exponent,
res,
expected
);
}
fn test_sets_as_base(sets: &[&[f64]], exponent: f64, expected: f64) {
@@ -468,31 +480,37 @@ mod tests {
}
fn test_sets(sets: &[&[f64]], computed: &Fn(f64) -> f64, expected: &Fn(f64) -> f64) {
sets.iter()
.for_each(|s| s.iter().for_each(|val| {
sets.iter().for_each(|s| {
s.iter().for_each(|val| {
let exp = expected(*val);
let res = computed(*val);
assert!(if exp.is_nan() {res.is_nan()} else {exp == res},
"test for {} was {} instead of {}", val, res, exp);
}));
assert!(
if exp.is_nan() {
res.is_nan()
} else {
exp == res
},
"test for {} was {} instead of {}",
val,
res,
exp
);
})
});
}
/// 1. (anything) ** 0 is 1
#[test]
fn zero_as_exponent() {
test_sets_as_base(ALL, 0.0, 1.0);
test_sets_as_base(ALL, -0.0, 1.0);
}
/// 2. 1 ** (anything) is 1
#[test]
fn one_as_base() {
test_sets_as_exponent(1.0, ALL, 1.0);
}
/// 3. (anything except 1) ** NAN is NAN
/// 4. NAN ** (anything except 0) is NAN
#[test]
fn nan_inputs() {
// NAN as the base:
@@ -504,10 +522,6 @@ mod tests {
test_sets_as_base(&ALL[..(ALL.len() - 2)], NAN, NAN);
}
/// 16. +INF ** (+anything except 0,NAN) is +INF
/// 17. +INF ** (-anything except 0,NAN) is +0
/// 18. -INF ** (+odd integer) is -INF
/// 19. -INF ** (anything) = -0 ** (-anything), (anything except odd integer)
#[test]
fn infinity_as_base() {
// Positive Infinity as the base:
@@ -527,11 +541,6 @@ mod tests {
test_sets(ALL, &|v: f64| pow(NEG_INFINITY, v), &|v: f64| pow(-0.0, -v));
}
/// 5. +-(|x| > 1) ** +INF is +INF
/// 6. +-(|x| > 1) ** -INF is +0
/// 7. +-(|x| < 1) ** +INF is +0
/// 8. +-(|x| < 1) ** -INF is +INF
/// 9. -1 ** +-INF is 1
#[test]
fn infinity_as_exponent() {
// Positive/Negative base greater than 1:
@@ -539,7 +548,7 @@ mod tests {
test_sets_as_base(&ALL[5..(ALL.len() - 2)], INFINITY, INFINITY);
// (pos/neg > 1 ^ -Infinity should be 0.0)
test_sets_as_base(&ALL[5..(ALL.len() - 2)], NEG_INFINITY, 0.0);
test_sets_as_base(&ALL[5..ALL.len() - 2], NEG_INFINITY, 0.0);
// Positive/Negative base less than 1:
let base_below_one = &[POS_ZERO, NEG_ZERO, NEG_SMALL_FLOATS, POS_SMALL_FLOATS];
@@ -558,12 +567,6 @@ mod tests {
test_sets_as_base(&[NEG_ONE, POS_ONE], NEG_INFINITY, 1.0);
}
/// 10. +0 ** (+anything except 0, NAN) is +0
/// 11. -0 ** (+anything except 0, NAN, odd integer) is +0
/// 12. +0 ** (-anything except 0, NAN) is +INF, raise divbyzero
/// 13. -0 ** (-anything except 0, NAN, odd integer) is +INF, raise divbyzero
/// 14. -0 ** (+odd integer) is -0
/// 15. -0 ** (-odd integer) is -INF, raise divbyzero
#[test]
fn zero_as_base() {
// Positive Zero as the base:
@@ -576,7 +579,7 @@ mod tests {
// Negative Zero as the base:
// (-0 ^ anything positive but 0, NAN, and odd ints should be +0)
test_sets_as_exponent(-0.0, &POS[3..], 0.0);
test_sets_as_exponent(-0.0, &POS[3..], 0.0);
// (-0 ^ anything negative but 0, NAN, and odd ints should be Infinity)
// (should panic because of divide by zero)