hugo/tpl/math/math.go
2020-12-03 13:12:58 +01:00

141 lines
3.8 KiB
Go

// Copyright 2017 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package math provides template functions for mathmatical operations.
package math
import (
"errors"
"math"
_math "github.com/gohugoio/hugo/common/math"
"github.com/spf13/cast"
)
// New returns a new instance of the math-namespaced template functions.
func New() *Namespace {
return &Namespace{}
}
// Namespace provides template functions for the "math" namespace.
type Namespace struct{}
// Add adds two numbers.
func (ns *Namespace) Add(a, b interface{}) (interface{}, error) {
return _math.DoArithmetic(a, b, '+')
}
// Ceil returns the least integer value greater than or equal to x.
func (ns *Namespace) Ceil(x interface{}) (float64, error) {
xf, err := cast.ToFloat64E(x)
if err != nil {
return 0, errors.New("Ceil operator can't be used with non-float value")
}
return math.Ceil(xf), nil
}
// Div divides two numbers.
func (ns *Namespace) Div(a, b interface{}) (interface{}, error) {
return _math.DoArithmetic(a, b, '/')
}
// Floor returns the greatest integer value less than or equal to x.
func (ns *Namespace) Floor(x interface{}) (float64, error) {
xf, err := cast.ToFloat64E(x)
if err != nil {
return 0, errors.New("Floor operator can't be used with non-float value")
}
return math.Floor(xf), nil
}
// Log returns the natural logarithm of a number.
func (ns *Namespace) Log(a interface{}) (float64, error) {
af, err := cast.ToFloat64E(a)
if err != nil {
return 0, errors.New("Log operator can't be used with non integer or float value")
}
return math.Log(af), nil
}
// Sqrt returns the square root of a number.
// NOTE: will return for NaN for negative values of a
func (ns *Namespace) Sqrt(a interface{}) (float64, error) {
af, err := cast.ToFloat64E(a)
if err != nil {
return 0, errors.New("Sqrt operator can't be used with non integer or float value")
}
return math.Sqrt(af), nil
}
// Mod returns a % b.
func (ns *Namespace) Mod(a, b interface{}) (int64, error) {
ai, erra := cast.ToInt64E(a)
bi, errb := cast.ToInt64E(b)
if erra != nil || errb != nil {
return 0, errors.New("modulo operator can't be used with non integer value")
}
if bi == 0 {
return 0, errors.New("the number can't be divided by zero at modulo operation")
}
return ai % bi, nil
}
// ModBool returns the boolean of a % b. If a % b == 0, return true.
func (ns *Namespace) ModBool(a, b interface{}) (bool, error) {
res, err := ns.Mod(a, b)
if err != nil {
return false, err
}
return res == int64(0), nil
}
// Mul multiplies two numbers.
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)
if err != nil {
return 0, errors.New("Round operator can't be used with non-float value")
}
return _round(xf), nil
}
// Sub subtracts two numbers.
func (ns *Namespace) Sub(a, b interface{}) (interface{}, error) {
return _math.DoArithmetic(a, b, '-')
}