Source code for bw2calc.least_squares

import warnings

import numpy as np
from scipy.sparse.linalg import lsmr

from bw2calc.errors import EfficiencyWarning, NoSolutionFound
from bw2calc.lca import LCA




class LeastSquaresLCA(LCA):
    """Solve overdetermined technosphere matrix with more products than activities using
    least-squares approximation.

    See also:

    * `Multioutput processes in LCA <http://chris.mutel.org/multioutput.html>`_
    * `LSMR in SciPy <http://docs.scipy.org/doc/scipy/reference/generated/scipy.sparse.linalg.lsmr.html#scipy.sparse.linalg.lsmr>`_  # noqa: E501
    * `Another least-squares algorithm in SciPy <http://docs.scipy.org/doc/scipy/reference/generated/scipy.sparse.linalg.lsqr.html#scipy.sparse.linalg.lsqr>`_  # noqa: E501

    """



    def load_lci_data(self) -> None:
        super().load_lci_data(nonsquare_ok=True)




    def solve_linear_system(self, solver=lsmr) -> np.ndarray:
        if self.technosphere_matrix.shape[0] == self.technosphere_matrix.shape[1]:
            warnings.warn("Don't use LeastSquaresLCA for square matrices", EfficiencyWarning)
        self.solver_results = solver(self.technosphere_matrix, self.demand_array)
        if self.solver_results[1] not in {1, 2}:
            warnings.warn(
                "No suitable solution found - supply array is probably nonsense",
                NoSolutionFound,
            )
        return self.solver_results[0]




    def decompose_technosphere(self) -> None:
        raise NotImplementedError("Can't decompose rectangular technosphere")