Add missing operations for fmpz and fmpq #44
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| def __lshift__(self, other): | ||
| if typecheck(other, fmpz): | ||
| other = int(other) | ||
| if typecheck(other, int): | ||
| u = fmpz.__new__(fmpz) | ||
| fmpz_mul_2exp((<fmpz>u).val, self.val, other) | ||
| return u |
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Probably need to check if other is negative.
test/test.py
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| assert ltype(s) & rtype(t) == s & t | ||
| assert ~ltype(s) == ~s | ||
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| # XXX: Some sort of bug here means that the following fails | ||
| # for values of s and t bigger than the word size. | ||
| if abs(s) < 2**62 and abs(t) < 2**62: | ||
| assert ltype(s) | rtype(t) == s | t | ||
| else: | ||
| # This still works so somehow the internal representation | ||
| # of the fmpz made by fmpz_or is such that fmpz_equal | ||
| # returns false even though the values look the same. | ||
| assert str(ltype(s) | rtype(t)) == str(s | t) | ||
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| assert ltype(s) ^ rtype(t) == s ^ t |
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I'm not sure what is happening here but I think that the __or__ method here is correct so maybe this is a Flint bug. The __and__ and __xor__ methods have the same code and tests and they work fine.
It seems that somehow fmpz_or creates an fmpz that fmpz_equal considers different even though its string representation is the same:
>>> flint.fmpz(2**62) | -1
-1
>>> flint.fmpz(2**62) | -1 == -1
False
>>> flint.fmpz(2**62-1) | -1
-1
>>> flint.fmpz(2**62-1) | -1 == -1
TrueI'm not sure how to debug this via python-flint.
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Yeah, this is a bug in fmpz_or. Fixed now in flintlib/flint@9809014.
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Okay, this PR is complete now and represents all of the changes needed for python-flint to be usable by SymPy as the ground types plus a few more for completeness. It is basically just adding missing operators/methods that are usually supported by implementations of Z or Q so that fmpz and fmpq can work better as a drop-in replacement for int/Fraction or gmpy2's mpz/mpq. There are still some differences e.g.: In [1]: import gmpy2
In [2]: import flint
In [3]: flint.fmpz(3) / flint.fmpz(2)
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
Cell In[3], line 1
----> 1 flint.fmpz(3) / flint.fmpz(2)
TypeError: unsupported operand type(s) for /: 'flint._flint.fmpz' and 'flint._flint.fmpz'
In [4]: gmpy2.mpz(3) / gmpy2.mpz(2)
Out[4]: mpfr('1.5')
In [5]: gmpy2.mpz(3.0)
Out[5]: mpz(3)
In [6]: flint.fmpz(3.0)
---------------------------------------------------------------------------
TypeError Traceback (most recent call last)
Cell In[6], line 1
----> 1 flint.fmpz(3.0)
File src/flint/fmpz.pyx:92, in flint._flint.fmpz.__init__()
TypeError: cannot create fmpz from type <class 'float'>These lead to a couple of doctest failures in SymPy but I think that it is something that can be handled on SymPy's side. The doctest for division is just a doctest saying not to use I will add a temporary fix for the |
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Okay, this looks good. I'll merge this and open a new PR to prepare for release. |
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This is a companion to the SymPy PR adding flint for ground types:
sympy/sympy#25474
Various things are added:
numerator/denominatorforfmpzandfmpq.__int__and__floor__methods.&etc forfmpzpow(a, b, c)forfmpz.fmpq ** fmpz.