fixed the overflow problem of powermod(x::Integer, p::Integer, m::T) #48192
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This isn't a great solution since it is type unstable and probably pretty slow. A better approach would probably be to compute |
I don't really see the type stability issue. |
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Good point. I forgot that the type of the exponent of |
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@oscardssmith @KristofferC Thanks! Maybe the BigInt can work, but I still think the fast exponentiation has higher performance and is more "elegant". I will revise it |
oscardssmith
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Jan 9, 2023
| @@ -267,6 +267,9 @@ end | |||
| @test powermod(2, -2, 5) == 4 | |||
| @test powermod(2, -1, -5) == -2 | |||
| @test powermod(2, -2, -5) == -1 | |||
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| @test powermod(2, typemin(Int128), 5) == 1 | |||
| @test powermod(2, typemin(Int128), -5) == -4 | |||
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add a test for BigInt power to make sure this still works for types without typemin.
Co-authored-by: Oscar Smith <oscardssmith@gmail.com>
oscardssmith
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Jan 11, 2023
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Thanks for the PR! |
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Fixed #48166