Comparison

Developer notes for include/stratax/ops/Comparison.hpp.

Purpose

Implements generic equality and inequality for Stratax array containers.

Main API

Array Comparison

• operator==
• operator!=

Invariants

• Equality never mutates either operand.
• Size or shape mismatch means arrays are not equal.
• Equal arrays must have the same flat element values in storage order.
• operator!= is always the logical negation of operator==.
• Comparison returns false for mismatched arrays instead of throwing.

Validation Notes

• Size or shape mismatch is checked with core::validation::same_shape() and returns false.
• Comparison does not throw for mismatched size or shape.
• Element comparison assumes both containers expose flat iteration in logical order.

Implementation Notes

• Equality checks size and shape first.
• Values are compared using iterators.
• Inequality delegates to equality.
• Works with vectors, matrices, and tensors.
• Shape compatibility comparison should stay routed through Validation.hpp.

Time Complexity

• Best case for mismatched size is O(1).
• Shape comparison is O(r).
• Equality is O(r + n) in the worst case.
• Inequality has the same complexity as equality.

Future Work

• Add approximate equality for floating-point containers.
• Add element-wise comparison arrays.
• Add tolerance controls.
• Add SIMD comparison paths.