felipecrv commented on code in PR #38426:
URL: https://github.com/apache/arrow/pull/38426#discussion_r1370568357
##########
go/arrow/decimal128/decimal128.go:
##########
@@ -266,23 +266,36 @@ func FromString(v string, prec, scale int32) (n Num, err
error) {
return
}
- // Since we're going to truncate this to get an integer, we need to
round
- // the value instead because of edge cases so that we match how other
implementations
- // (e.g. C++) handles Decimal values. So if we're negative we'll
subtract 0.5 and if
- // we're positive we'll add 0.5.
- out.Mul(out, big.NewFloat(math.Pow10(int(scale)))).SetPrec(precInBits)
- if out.Signbit() {
- out.Sub(out, pt5)
+ if scale < 0 {
+ var tmp big.Int
+ val, _ := out.Int(&tmp)
+ if val.BitLen() > 127 {
+ return Num{}, errors.New("bitlen too large for
decimal128")
+ }
+ n = FromBigInt(val)
+ n, _ = n.Div(scaleMultipliers[-scale])
} else {
- out.Add(out, pt5)
- }
- var tmp big.Int
- val, _ := out.Int(&tmp)
- if val.BitLen() > 127 {
- return Num{}, errors.New("bitlen too large for decimal128")
+ // Since we're going to truncate this to get an integer, we
need to round
+ // the value instead because of edge cases so that we match how
other implementations
+ // (e.g. C++) handles Decimal values. So if we're negative
we'll subtract 0.5 and if
+ // we're positive we'll add 0.5.
+ p := (&big.Float{}).SetFloat64(float64PowersOfTen[scale+38])
Review Comment:
Saw the fix on the next commit.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
