DEA的Matlab程序

function [zmax,xbasic,ibasic]=PPL(A,b,c); % % A forma de escrever a funçao eh: PPL(A,b,c) % a funçao retorna 3 valores, em ordem: zmax - valor maximizado da F.O. (eficiencia), xbasic - valores das soluçoes basicas, % ibasic - indice das soluçoes basicas % % Esta funçao nao explica os valores, serve apenas de modulo para o DEASolver. Para conseguir soluçoes de PPL, % usar o linprog original % % Usa o metodo Simplex Generalizado, de 2 fases, aceitando restriçoes >=, <= ou =, desde que as matrizes sejam inseridas % sempre na forma Max cx tal que Ax=b. % % Baseado no codigo linprog referenciado abaixo % Written by Jeff Stuart, Department of Mathematics, % University of Southern Mississippi, Hattiesburg, MS 39406. % December, 1993. Revised, October, 1997. % jeffrey.stuart@usm.edu % [m,n]=size(A); % verificando dimensoes b X A if max(size(b) ~=[m 1]); disp('The dimensions of b do not match the dimensions of A.') break end % Positividade de b if min(b) < 0; disp('The RHS vector b must be nonnegative.') break end % Verificando dimensoes c X A if max(size(c) ~=[1 n]); disp('The dimensions of c do not match the dimensions of A.') break end if rank(A) ~=m; disp('A does not have full row rank.') break end t=cputime; PHIiter=0; PHIIiter=0; tol=0.0000000001; xbasic=zeros(1,n); % Roda a fase I [wmax,ibasic,PHIiter]=phasei(A,b); if wmax < -tol ; t=cputime -t; disp('The original LP is infeasible. Infeasibility was') disp('detected during Phase I. The total number of phase') disp('one iterations performed was: '), disp(PHIiter) else; % roda a fase 2 [zmax,xbasic,ibasic,ienter,PHIIiter,PCOL,OPTEST,CYCTEST]=phaseii(A,b,c,ibasic); xbasic=xbasic'; t=cputime -t; if CYCTEST==1; break end if OPTEST == 0; disp('The orginal LP is unbounded. An unbounded ray was') disp('detected during Phase II. The output objective') disp('value is for the last basic solution found.') disp('The number of Phase II iterations was: '),disp(PHIIiter) disp('Last objective value is '),disp(zmax) disp('The last basic solution, xbasic is '),disp(xbasic) disp('The column indices for the last basis: '),disp(ibasic) disp('The index of the unbounded entering variable: '),disp(ienter) disp('The unbounded ray column is: '),disp(PCOL) disp('The required cpu time was: '),disp(t) end end