photoprism/pkg/txt/float.go

97 lines
1.6 KiB
Go

package txt
import (
"errors"
"strconv"
"strings"
)
// IsFloat checks if the string represents a floating point number.
func IsFloat(s string) bool {
if s == "" {
return false
}
s = strings.TrimSpace(s)
for _, r := range s {
if r != '.' && r != ',' && (r < '0' || r > '9') {
return false
}
}
return true
}
// Float converts a string to a 64-bit floating point number or 0 if invalid.
func Float(s string) float64 {
if s == "" {
return 0
}
f, err := strconv.ParseFloat(Numeric(s), 64)
if err != nil {
return 0
}
return f
}
// Float32 converts a string to a 32-bit floating point number or 0 if invalid.
func Float32(s string) float32 {
return float32(Float(s))
}
// FloatRange parses a string as floating point number range and returns an error if it's not a valid range.
func FloatRange(s string, min, max float64) (start float64, end float64, err error) {
if s == "" || len(s) > 40 {
return start, end, errors.New("invalid range")
}
valid := false
p := 0
v := [][]byte{make([]byte, 0, 20), make([]byte, 0, 20)}
for i, r := range s {
if r == 45 {
if i == 0 || p == 1 {
v[p] = append(v[p], byte(r))
} else if p == 0 {
p = 1
}
}
if r == 46 || r >= 48 && r <= 57 {
valid = true
v[p] = append(v[p], byte(r))
}
}
if !valid {
return start, end, errors.New("invalid range")
}
if p == 0 {
start = Float(string(v[0]))
end = start
} else {
start = Float(string(v[0]))
end = Float(string(v[1]))
}
if start > max {
start = max
} else if start < min {
start = min
}
if end > max {
end = max
} else if end < min {
end = min
}
return start, end, nil
}