Add math.Pow

Closes #7266
This commit is contained in:
Joe Mooring 2020-05-13 13:35:07 -04:00 committed by Bjørn Erik Pedersen
parent 558c09305e
commit 991934497e
4 changed files with 60 additions and 1 deletions

View file

@ -38,4 +38,4 @@ aliases: []
| `math.Round` | Returns the nearest integer, rounding half away from zero. | `{{math.Round 1.5}}` → `2` |
| `math.Log` | Returns the natural logarithm of the given number. | `{{math.Log 42}}` → `3.737` |
| `math.Sqrt` | Returns the square root of the given number. | `{{math.Sqrt 81}}` → `9` |
| `math.Pow` | Returns the first number raised to the power of the second number. | `{{math.Pow 2 3}}` → `8` |

View file

@ -92,6 +92,13 @@ func init() {
},
)
ns.AddMethodMapping(ctx.Pow,
[]string{"pow"},
[][2]string{
{"{{math.Pow 2 3}}", "8"},
},
)
ns.AddMethodMapping(ctx.Round,
nil,
[][2]string{

View file

@ -115,6 +115,18 @@ func (ns *Namespace) Mul(a, b interface{}) (interface{}, error) {
return _math.DoArithmetic(a, b, '*')
}
// Pow returns a raised to the power of b.
func (ns *Namespace) Pow(a, b interface{}) (float64, error) {
af, erra := cast.ToFloat64E(a)
bf, errb := cast.ToFloat64E(b)
if erra != nil || errb != nil {
return 0, errors.New("Pow operator can't be used with non-float value")
}
return math.Pow(af, bf), nil
}
// Round returns the nearest integer, rounding half away from zero.
func (ns *Namespace) Round(x interface{}) (float64, error) {
xf, err := cast.ToFloat64E(x)

View file

@ -318,3 +318,43 @@ func TestRound(t *testing.T) {
c.Assert(result, qt.Equals, test.expect)
}
}
func TestPow(t *testing.T) {
t.Parallel()
c := qt.New(t)
ns := New()
for _, test := range []struct {
a interface{}
b interface{}
expect interface{}
}{
{0, 0, float64(1)},
{2, 0, float64(1)},
{2, 3, float64(8)},
{-2, 3, float64(-8)},
{2, -3, float64(0.125)},
{-2, -3, float64(-0.125)},
{0.2, 3, float64(0.008)},
{2, 0.3, float64(1.2311)},
{0.2, 0.3, float64(0.617)},
{"aaa", "3", false},
{"2", "aaa", false},
} {
result, err := ns.Pow(test.a, test.b)
if b, ok := test.expect.(bool); ok && !b {
c.Assert(err, qt.Not(qt.IsNil))
continue
}
// we compare only 4 digits behind point if its a real float
// otherwise we usually get different float values on the last positions
result = float64(int(result*10000)) / 10000
c.Assert(err, qt.IsNil)
c.Assert(result, qt.Equals, test.expect)
}
}