petsc4py.typing.NormTypeSpec#

petsc4py.typing.NormTypeSpec = petsc4py.PETSc.NormType | None#

Norm type specification.

Possible values include:

NormType.NORM_1 The 1-norm: Σₙ abs(xₙ) for vectors, maxₙ (Σᵢ abs(xₙᵢ)) for matrices.
NormType.NORM_2 The 2-norm: √(Σₙ xₙ²) for vectors, largest singular values for matrices.
NormType.NORM_INFINITY The ∞-norm: maxₙ abs(xₙ) for vectors, maxᵢ (Σₙ abs(xₙᵢ)) for matrices.
NormType.NORM_FROBENIUS The Frobenius norm: same as 2-norm for vectors, √(Σₙᵢ xₙᵢ²) for matrices.
NormType.NORM_1_AND_2 Compute both NormType.NORM_1 and NormType.NORM_2.
None as NormType.NORM_2 for vectors, NormType.NORM_FROBENIUS for matrices.