Structures · Algebra
Field
A Field is a CommRing with multiplicative inverses for nonzero elements.
An instance of Field K includes maps ratCast : ℚ → K and qsmul : ℚ → K → K.
Those two fields are needed to implement the DivisionRing K → Algebra ℚ K instance since we need
to control the specific definitions for some special cases of K (in particular K = ℚ itself).
See also note [forgetful inheritance].
If the field has positive characteristic p, our division by zero convention forces
ratCast (1 / p) = 1 / 0 = 0.
- Defined in
- Mathlib.Algebra.Field.Defs
- Shape
- One type argument · adds div_eq_mul_inv, zpow_zero', zpow_succ', zpow_neg', mul_inv_cancel, inv_zero, nnratCast_def, nnqsmul, nnqsmul_def, ratCast_def, qsmul, qsmul_def
Extends2
Extended by1
Forgetful instances
Every Field is also a
Concrete types that are instances41
- Real
- Rat
- Complex
- ZMod
- Filter.Germ
- Padic
- CommRingCat.carrier
- RatFunc
- UniformSpace.Completion
- IsDedekindDomain.HeightOneSpectrum.adicCompletion
- FractionRing
- WithVal
- HahnSeries
- QuadraticAlgebra
- Hyperreal
- ArchimedeanClass.FiniteResidueField
- DirectLimit
- IsLocalRing.ResidueField
- Polynomial.SplittingField
- RatFunc.CompletionAtInfty
- AbstractCompletion.space
- GaloisField
- FiniteField.Extension
- CauSeq.Completion.Cauchy
- AlgebraicClosure
- PerfectClosure
- AdjoinRoot
- OreLocalization
- CyclotomicField
- Polynomial.SplittingFieldAux
- AdjoinPthRoots
- Tilt
- AlgebraicGeometry.ValuativeCommSq.K
- Subtype
- OrderDual
- ULift
- MulOpposite
- Lex
- AddOpposite
- Shrink
- WithAbs
How is a type an instance?
Loading the hierarchy index…
Assumed by9,076
- NumberField.InfinitePlace
- NumberField.RingOfIntegers
- IntermediateField.adjoin
- NumberField.InfinitePlace.IsReal
- NumberField.InfinitePlace.IsComplex
- NumberField.mixedEmbedding.mixedSpace
- CauSeq
- slope
- IntermediateField.toSubalgebra
- IsDedekindDomain.HeightOneSpectrum.valuation
- NumberField.InfinitePlace.mult
- IsCauSeq
- NumberField.mixedEmbedding.realSpace
- IntermediateField.LinearDisjoint
- NumberField.InfinitePlace.embedding
- NumberField.RingOfIntegers.val
- IsPrimitiveRoot.toInteger
- NumberField.Units.dirichletUnitTheorem.w₀
- NumberField.place
- FormalMultilinearSeries.ofScalars
- NormedSpace.expSeries
- IntermediateField.restrictScalars
- Height.mulHeight
- IntermediateField.map
- CauSeq.Completion.Cauchy
- IntermediateField.subset_adjoin
- RatFunc.denom
- CauSeq.const
- AlgHom.fieldRange
- Valuation.valuationSubring
- IntermediateField.AdjoinSimple.gen
- separableClosure
- NumberField.InfinitePlace.comap
- WeierstrassCurve.Affine.slope
- Polynomial.natSepDegree
- NumberField.discr
- NumberField.Units.torsion
- AlgebraicClosure
- NumberField.mixedEmbedding
- NumberField.InfinitePlace.nrComplexPlaces
- RatFunc.num
- Finset.centerMass
- NumberField.mixedEmbedding.norm
- CauSeq.LimZero
- NumberField.Units.dirichletUnitTheorem.logSpace
- NumberField.Units.rank
- IntermediateField.relrank
- NumberField.mixedEmbedding.normAtPlace
- FractionRing.liftAlgebra
- Polynomial.SplittingField
Ancestors118
- Add
- AddAction
- AddCancelCommMonoid
- AddCancelMonoid
- AddCommGroup
- AddCommGroupWithOne
- AddCommMagma
- AddCommMonoid
- AddCommMonoidWithOne
- AddCommSemigroup
- AddGroup
- AddGroupWithOne
- AddLeftCancelMonoid
- AddLeftCancelSemigroup
- AddMonoid
- AddMonoidWithOne
- AddRightCancelMonoid
- AddRightCancelSemigroup
- AddSemigroup
- AddSemigroupAction
- AddTorsor
- AddZero
- AddZeroClass
- Bracket
- CommGroupWithZero
- CommMagma
- CommMonoid
- CommMonoidWithZero
- CommRing
- CommSemigroup
- CommSemiring
- Distrib
- Div
- DivInvMonoid
- DivInvOneMonoid
- DivisionCommMonoid
- DivisionMonoid
- DivisionRing
- DivisionSemiring
- Dvd
- EuclideanDomain
- GroupWithZero
- HAdd
- HDiv
- HMod
- HMul
- HSMul
- HSub
- HVAdd
- Ideal.FiniteHeight
- IntCast
- Inv
- InvOneClass
- InvolutiveInv
- InvolutiveNeg
- IsJacobsonRing
- IsLeftCancelAdd
- IsRightCancelAdd
- IsSemiprimaryRing
- Lean.Grind.AddCommGroup
- Lean.Grind.AddCommMonoid
- Lean.Grind.CommRing
- Lean.Grind.CommSemiring
- Lean.Grind.Field
- Lean.Grind.IntModule
- Lean.Grind.NatModule
- Lean.Grind.Ring
- Lean.Grind.Semiring
- Mod
- Monoid
- MonoidWithZero
- Mul
- MulAction
- MulOne
- MulOneClass
- MulZeroClass
- MulZeroOneClass
- NNRatCast
- NPow
- NSMul
- NatCast
- Neg
- NegZeroClass
- NonAssocCommRing
- NonAssocCommSemiring
- NonAssocRing
- NonAssocSemiring
- NonUnitalCommRing
- NonUnitalCommSemiring
- NonUnitalNonAssocCommRing
- NonUnitalNonAssocCommSemiring
- NonUnitalNonAssocRing
- NonUnitalNonAssocSemiring
- NonUnitalRing
- NonUnitalSemiring
- Nonempty
- Nontrivial
- OfNat
- OfScientific
- One
- RatCast
- Ring
- SMul
- Semifield
- Semigroup
- SemigroupAction
- SemigroupWithZero
- Semiring
- Sub
- SubNegMonoid
- SubNegZeroMonoid
- SubtractionCommMonoid
- SubtractionMonoid
- VAdd
- VSub
- ZPow
- ZSMul
- Zero