Refactor lcp & bimatrix initialization

[nataliemes]

• payoffmatrix and bimatrix classes' redundant __init__() definitions (that were commented out) were removed.

• Previously, lcp's __init__() method behaved differently based on the type of the argument:

  • for an integer, it created an lcp instance of that dimension with all entries set to 0;
  • for a string, it created an lcp instance after parsing a file with that name.

  Now _init__() accepts 3 arguments: M, q, d. Reading from a file is done by a class method from_file, which accepts a string argument for a filename and returns the parsed lcp object.

• bimatrix's __init__() was refactored in the same way: it accepts A, B payoff matrices directly and a class method from_file builds a bimatrix object after parsing a file.

Note

These __init__() methods should have error checking (for example, to verify that given vectors/matrices have the right dimensions) – this will be done later in a separate PR that updates error handling.

[Copilot]

Pull request overview

This PR refactors object construction for the core LCP (lcp) and bimatrix game (bimatrix) data structures by separating “parse from file” behavior into explicit from_file(...) class methods, while making __init__ accept the underlying data directly. This clarifies the APIs and removes type-dependent constructor behavior.

Changes:

• Refactor lcp.__init__ to accept (M, q, d) directly and add lcp.from_file(...) for parsing.
• Refactor bimatrix.__init__ to accept (A, B) directly and add bimatrix.from_file(...) for parsing.
• Update tests and helpers to use the new constructors / from_file entrypoints.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/test_lemke.py	Updates LCP parsing tests to use lcp.from_file and introduces a helper for constructing empty LCPs under the new API.
tests/test_lcp.py	Migrates fixture-based LCP construction from lcp(path) to lcp.from_file(path).
tests/test_bimatrix.py	Migrates fixture-based bimatrix construction from bimatrix(path) to bimatrix.from_file(path).
tests/sequence_form_helper.py	Updates helper to construct lcp(M, q, d) directly rather than creating then mutating an empty instance.
src/lemke/lemke.py	Implements new lcp(M, q, d) + lcp.from_file(...) API and updates CLI entry to use from_file.
src/lemke/bimatrix.py	Implements new bimatrix(A, B) + bimatrix.from_file(...) API and updates LCP creation to build (M, q, d) directly.

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[rahulsavani]

Looks good to me.