[Bug] using SumS on a ushort[] throws System.InvalidCastException

Question

[Bug] using SumS on a ushort[] throws System.InvalidCastException

Smurf-IV opened this issue 5 years ago · comments

Code:

                    ushort[] pRowArrayClip = samePool.Rent(countClip);
                    Array.Copy(pRowArrayFull, pRowArrayClip, countClip);
                    double average = pRowArrayClip.SumS();

Exception:

                   System.InvalidCastException : Specified cast is not valid.
                       at JM.LinqFaster.SIMD.LinqFasterSIMD.SumS[T](T[] source)
                       at #########

Simon Coghlan · Answer 1 · Fri Jul 19 2019 22:47:04 GMT+0800 (China Standard Time)

Should ushort not be supported

Jack Mott · Answer 2 · Fri Jul 19 2019 23:05:15 GMT+0800 (China Standard Time)

not sure, it looks like it should work, I'll investigate

Simon Coghlan · Answer 3 · Fri Jul 19 2019 23:10:57 GMT+0800 (China Standard Time)

ushort[].Sum() from normal linq does not appear to be supported (And also not in SumF)

Simon Coghlan · Answer 4 · Fri Jul 19 2019 23:11:26 GMT+0800 (China Standard Time)

What would the expected result be a Double ? Decimal ????

Jack Mott · Answer 5 · Fri Jul 19 2019 23:13:16 GMT+0800 (China Standard Time)

the result of a sum on ushort should be a ushort, the way it is currently implemented.

which, won't typically be useful!

probably why linq doesn't support it.

Jack Mott · Answer 6 · Fri Jul 19 2019 23:22:11 GMT+0800 (China Standard Time)

ok the problem is that a ushort + a ushort = an int32.
So, this could be supported if instead of using a generic sum method, we made one for each type, and ushort returned an int32 for the sum.

that's a bunch of grunt work though.

Jack Mott · Answer 7 · Fri Jul 19 2019 23:32:22 GMT+0800 (China Standard Time)

output type always the same as input type currently, same as linq.

…

On Fri, Jul 19, 2019 at 10:11 AM Simon Coghlan ***@***.***> wrote: What would the expected result be a Double ? Decimal ???? — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#18?email_source=notifications&email_token=ABD3XZR4UZSJLSUCKOXOQ6DQAHKR7A5CNFSM4IFGOQQ2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOD2L5IKI#issuecomment-513266729>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABD3XZQONZFFV4QNGDBSTNDQAHKR7ANCNFSM4IFGOQQQ> .

Simon Coghlan · Answer 8 · Sun Jul 21 2019 14:42:23 GMT+0800 (China Standard Time)

probably why linq doesn't support it.
So this should mean that this implementation not allow it to be used for ushort's, and not allow it to compile (As per linq)

Simon Coghlan · Answer 9 · Sat Aug 03 2019 15:36:59 GMT+0800 (China Standard Time)

ok the problem is that a ushort + a ushort = an int32.
So, this could be supported if instead of using a generic sum method, we made one for each type, and ushort returned an int32 for the sum.

that's a bunch of grunt work though.

Work done in the pending #20

Convert SumF function into a generic function
Add new managed types (sbyte, byte, short, ushort, int, uint, long, ulong)
Add tests for some of the new types
Add new Benchmark tests