A better scalar Preisach algorithm

A Preisach hysteresis model for the case in which Everett´s function, E(H₁, H₂), has been defined from measurements of the magnetization change from a turning point H₁ to the field H₂. E(H₁, H ₂) is the integral of the Preisach density function, whose symmetry imposes the relation E(H₁, H ₂)=E(-H₁, -H₂ ). This is inconsistent with measured first-order curves. The source of the inconsistency is that magnetization changes depend on the state of the medium, not just the most recent turning point as Preisach assumes. A Preisach-like algorithm is proposed that is consistently defined by first-order curves and that predicts magnetization changes based on the state of the medium. The algorithm maintains a turning-point history and predicts closed minor loops, like the traditional model, but also predicts noncongruent minor loops and nonzero initial susceptibility