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Enums & Coercion

The solver functions accept EProduct and EInv enum values to control which GA product is used and whether involutions (reverse, conjugate) are applied to operands. They also accept scalars and strings in place of MV instances.

EProduct — choosing the GA operation

from pytanga.enums import EProduct
Value Operation Description
EProduct.GP Geometric product (*) The full GA product
EProduct.IP Inner product (|) The contraction / inner product
EProduct.OP Outer product (^) The wedge / outer product

Solvers and matrix functions accept a product keyword:

from pytanga.solver.solve import solve

X = solve(A, Y, product='op', algebra=alg)

from pytanga.matrix.product import product_matrix
M = product_matrix(A, b_mask=b_mask, c_mask=c_mask, product=EProduct.IP)

The default is EProduct.GP.

EInv — operand involutions

from pytanga.enums import EInv
Value Sign pattern What it does
EInv.ID None Identity (default)
EInv.REV (-1)^(k(k-1)/2) Reverse: negates grades 2, 3 mod 4
EInv.CONJ (-1)^(k(k-1)/2 + r) Clifford conjugate: reverse + negative‑metric sign

EInv is a StrEnum, so EInv.REV == "rev" is True.

Both the solvers and product_matrix accept left_inv and right_inv:

from pytanga.enums import EInv
from pytanga.solver.solve import solve

# Solve rev(A) * X = C
X = solve(A, C, left_inv=EInv.REV, algebra=alg)

# Build product matrix with rev on A, conj on X
M = product_matrix(A, b_mask=b_mask, c_mask=c_mask,
                   left_inv=EInv.REV, right_inv=EInv.CONJ)

Default: both left_inv and right_inv default to EInv.ID.

Input coercion (MVLike)

Every solver function that expects a multivector also accepts:

Input type Behaviour
MV Used directly
int / float Coerced to the scalar MV
str Parsed with the same grammar as Algebra("...")
list[MV] Batch of MVs (for solve_lsq, product_matrix) 
solve(A, 1.0, algebra=alg)              # 1.0 → scalar MV
solve(A, "e1", algebra=alg)             # "e1" → MV with e1=1
solve(A, "2e1 - e2", algebra=alg)       # parsed expression