source: code/trunk/vendor/github.com/dustin/go-humanize/commaf.go@ 822

// +build go1.6

package humanize

import (
        "bytes"
        "math/big"
        "strings"
)

// BigCommaf produces a string form of the given big.Float in base 10
// with commas after every three orders of magnitude.
func BigCommaf(v *big.Float) string {
        buf := &bytes.Buffer{}
        if v.Sign() < 0 {
                buf.Write([]byte{'-'})
                v.Abs(v)
        }

        comma := []byte{','}

        parts := strings.Split(v.Text('f', -1), ".")
        pos := 0
        if len(parts[0])%3 != 0 {
                pos += len(parts[0]) % 3
                buf.WriteString(parts[0][:pos])
                buf.Write(comma)
        }
        for ; pos < len(parts[0]); pos += 3 {
                buf.WriteString(parts[0][pos : pos+3])
                buf.Write(comma)
        }
        buf.Truncate(buf.Len() - 1)

        if len(parts) > 1 {
                buf.Write([]byte{'.'})
                buf.WriteString(parts[1])
        }
        return buf.String()
}