diff options
Diffstat (limited to 'vendor/github.com/json-iterator/go/stream_float.go')
-rw-r--r-- | vendor/github.com/json-iterator/go/stream_float.go | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/vendor/github.com/json-iterator/go/stream_float.go b/vendor/github.com/json-iterator/go/stream_float.go new file mode 100644 index 00000000..826aa594 --- /dev/null +++ b/vendor/github.com/json-iterator/go/stream_float.go @@ -0,0 +1,111 @@ +package jsoniter + +import ( + "fmt" + "math" + "strconv" +) + +var pow10 []uint64 + +func init() { + pow10 = []uint64{1, 10, 100, 1000, 10000, 100000, 1000000} +} + +// WriteFloat32 write float32 to stream +func (stream *Stream) WriteFloat32(val float32) { + if math.IsInf(float64(val), 0) || math.IsNaN(float64(val)) { + stream.Error = fmt.Errorf("unsupported value: %f", val) + return + } + abs := math.Abs(float64(val)) + fmt := byte('f') + // Note: Must use float32 comparisons for underlying float32 value to get precise cutoffs right. + if abs != 0 { + if float32(abs) < 1e-6 || float32(abs) >= 1e21 { + fmt = 'e' + } + } + stream.buf = strconv.AppendFloat(stream.buf, float64(val), fmt, -1, 32) +} + +// WriteFloat32Lossy write float32 to stream with ONLY 6 digits precision although much much faster +func (stream *Stream) WriteFloat32Lossy(val float32) { + if math.IsInf(float64(val), 0) || math.IsNaN(float64(val)) { + stream.Error = fmt.Errorf("unsupported value: %f", val) + return + } + if val < 0 { + stream.writeByte('-') + val = -val + } + if val > 0x4ffffff { + stream.WriteFloat32(val) + return + } + precision := 6 + exp := uint64(1000000) // 6 + lval := uint64(float64(val)*float64(exp) + 0.5) + stream.WriteUint64(lval / exp) + fval := lval % exp + if fval == 0 { + return + } + stream.writeByte('.') + for p := precision - 1; p > 0 && fval < pow10[p]; p-- { + stream.writeByte('0') + } + stream.WriteUint64(fval) + for stream.buf[len(stream.buf)-1] == '0' { + stream.buf = stream.buf[:len(stream.buf)-1] + } +} + +// WriteFloat64 write float64 to stream +func (stream *Stream) WriteFloat64(val float64) { + if math.IsInf(val, 0) || math.IsNaN(val) { + stream.Error = fmt.Errorf("unsupported value: %f", val) + return + } + abs := math.Abs(val) + fmt := byte('f') + // Note: Must use float32 comparisons for underlying float32 value to get precise cutoffs right. + if abs != 0 { + if abs < 1e-6 || abs >= 1e21 { + fmt = 'e' + } + } + stream.buf = strconv.AppendFloat(stream.buf, float64(val), fmt, -1, 64) +} + +// WriteFloat64Lossy write float64 to stream with ONLY 6 digits precision although much much faster +func (stream *Stream) WriteFloat64Lossy(val float64) { + if math.IsInf(val, 0) || math.IsNaN(val) { + stream.Error = fmt.Errorf("unsupported value: %f", val) + return + } + if val < 0 { + stream.writeByte('-') + val = -val + } + if val > 0x4ffffff { + stream.WriteFloat64(val) + return + } + precision := 6 + exp := uint64(1000000) // 6 + lval := uint64(val*float64(exp) + 0.5) + stream.WriteUint64(lval / exp) + fval := lval % exp + if fval == 0 { + return + } + stream.writeByte('.') + for p := precision - 1; p > 0 && fval < pow10[p]; p-- { + stream.writeByte('0') + } + stream.WriteUint64(fval) + for stream.buf[len(stream.buf)-1] == '0' { + stream.buf = stream.buf[:len(stream.buf)-1] + } +} |