diff options
Diffstat (limited to 'vendor/github.com/json-iterator/go/feature_stream_float.go')
-rw-r--r-- | vendor/github.com/json-iterator/go/feature_stream_float.go | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/vendor/github.com/json-iterator/go/feature_stream_float.go b/vendor/github.com/json-iterator/go/feature_stream_float.go new file mode 100644 index 000000000..9a404e11d --- /dev/null +++ b/vendor/github.com/json-iterator/go/feature_stream_float.go @@ -0,0 +1,96 @@ +package jsoniter + +import ( + "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) { + 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.WriteRaw(strconv.FormatFloat(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 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('.') + stream.ensure(10) + for p := precision - 1; p > 0 && fval < pow10[p]; p-- { + stream.writeByte('0') + } + stream.WriteUint64(fval) + for stream.buf[stream.n-1] == '0' { + stream.n-- + } +} + +// WriteFloat64 write float64 to stream +func (stream *Stream) WriteFloat64(val float64) { + 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.WriteRaw(strconv.FormatFloat(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 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('.') + stream.ensure(10) + for p := precision - 1; p > 0 && fval < pow10[p]; p-- { + stream.writeByte('0') + } + stream.WriteUint64(fval) + for stream.buf[stream.n-1] == '0' { + stream.n-- + } +} |