1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193
|
;;; SIMPLEX -- Simplex algorithm.
(library (r6rs-benchmarks simplex)
(export main)
(import (r6rs) (r6rs arithmetic flonums) (r6rs-benchmarks))
(define (matrix-rows a) (vector-length a))
(define (matrix-columns a) (vector-length (vector-ref a 0)))
(define (matrix-ref a i j) (vector-ref (vector-ref a i) j))
(define (matrix-set! a i j x) (vector-set! (vector-ref a i) j x))
(define (fuck-up)
(fatal-error "This shouldn't happen"))
(define (simplex a m1 m2 m3)
;(define *epsilon* 1e-6)
(define *epsilon* 0.000001)
(if (not (and (>= m1 0)
(>= m2 0)
(>= m3 0)
(= (matrix-rows a) (+ m1 m2 m3 2))))
(fuck-up))
(let* ((m12 (+ m1 m2 1))
(m (- (matrix-rows a) 2))
(n (- (matrix-columns a) 1))
(l1 (make-vector n))
(l2 (make-vector m))
(l3 (make-vector m2))
(nl1 n)
(iposv (make-vector m))
(izrov (make-vector n))
(ip 0)
(kp 0)
(bmax 0.0)
(one? #f)
(pass2? #t))
(define (simp1 mm abs?)
(set! kp (vector-ref l1 0))
(set! bmax (matrix-ref a mm kp))
(do ((k 1 (+ k 1))) ((>= k nl1))
(if (flpositive?
(if abs?
(fl- (flabs (matrix-ref a mm (vector-ref l1 k)))
(flabs bmax))
(fl- (matrix-ref a mm (vector-ref l1 k)) bmax)))
(begin
(set! kp (vector-ref l1 k))
(set! bmax (matrix-ref a mm (vector-ref l1 k)))))))
(define (simp2)
(set! ip 0)
(let ((q1 0.0)
(flag? #f))
(do ((i 0 (+ i 1))) ((= i m))
(if flag?
(if (fl<? (matrix-ref a (vector-ref l2 i) kp) (fl- *epsilon*))
(begin
(let ((q (fl/ (fl- (matrix-ref a (vector-ref l2 i) 0))
(matrix-ref a (vector-ref l2 i) kp))))
(cond
((fl<? q q1)
(set! ip (vector-ref l2 i))
(set! q1 q))
((fl=? q q1)
(let ((qp 0.0)
(q0 0.0))
(let loop ((k 1))
(if (<= k n)
(begin
(set! qp (fl/ (fl- (matrix-ref a ip k))
(matrix-ref a ip kp)))
(set! q0 (fl/ (fl-
(matrix-ref a (vector-ref l2 i) k))
(matrix-ref a (vector-ref l2 i) kp)))
(if (fl=? q0 qp)
(loop (+ k 1))))))
(if (fl<? q0 qp)
(set! ip (vector-ref l2 i)))))))))
(if (fl<? (matrix-ref a (vector-ref l2 i) kp) (fl- *epsilon*))
(begin
(set! q1 (fl/ (fl- (matrix-ref a (vector-ref l2 i) 0))
(matrix-ref a (vector-ref l2 i) kp)))
(set! ip (vector-ref l2 i))
(set! flag? #t)))))))
(define (simp3 one?)
(let ((piv (fl/ (matrix-ref a ip kp))))
(do ((ii 0 (+ ii 1))) ((= ii (+ m (if one? 2 1))))
(if (not (= ii ip))
(begin
(matrix-set! a ii kp (fl* piv (matrix-ref a ii kp)))
(do ((kk 0 (+ kk 1))) ((= kk (+ n 1)))
(if (not (= kk kp))
(matrix-set! a ii kk (fl- (matrix-ref a ii kk)
(fl* (matrix-ref a ip kk)
(matrix-ref a ii kp)))))))))
(do ((kk 0 (+ kk 1))) ((= kk (+ n 1)))
(if (not (= kk kp))
(matrix-set! a ip kk (fl* (fl- piv) (matrix-ref a ip kk)))))
(matrix-set! a ip kp piv)))
(do ((k 0 (+ k 1))) ((= k n))
(vector-set! l1 k (+ k 1))
(vector-set! izrov k k))
(do ((i 0 (+ i 1))) ((= i m))
(if (flnegative? (matrix-ref a (+ i 1) 0))
(fuck-up))
(vector-set! l2 i (+ i 1))
(vector-set! iposv i (+ n i)))
(do ((i 0 (+ i 1))) ((= i m2)) (vector-set! l3 i #t))
(if (positive? (+ m2 m3))
(begin
(do ((k 0 (+ k 1))) ((= k (+ n 1)))
(do ((i (+ m1 1) (+ i 1)) (sum 0.0 (fl+ sum (matrix-ref a i k))))
((> i m) (matrix-set! a (+ m 1) k (fl- sum)))))
(let loop ()
(simp1 (+ m 1) #f)
(cond
((fl<=? bmax *epsilon*)
(cond ((fl<? (matrix-ref a (+ m 1) 0) (fl- *epsilon*))
(set! pass2? #f))
((fl<=? (matrix-ref a (+ m 1) 0) *epsilon*)
(let loop ((ip1 m12))
(if (<= ip1 m)
(cond ((= (vector-ref iposv (- ip1 1)) (+ ip n -1))
(simp1 ip1 #t)
(cond ((flpositive? bmax)
(set! ip ip1)
(set! one? #t))
(else
(loop (+ ip1 1)))))
(else
(loop (+ ip1 1))))
(do ((i (+ m1 1) (+ i 1))) ((>= i m12))
(if (vector-ref l3 (- i (+ m1 1)))
(do ((k 0 (+ k 1))) ((= k (+ n 1)))
(matrix-set! a i k (fl- (matrix-ref a i k)))))))))
(else (simp2) (if (zero? ip) (set! pass2? #f) (set! one? #t)))))
(else (simp2) (if (zero? ip) (set! pass2? #f) (set! one? #t))))
(if one?
(begin
(set! one? #f)
(simp3 #t)
(cond
((>= (vector-ref iposv (- ip 1)) (+ n m12 -1))
(let loop ((k 0))
(cond
((and (< k nl1) (not (= kp (vector-ref l1 k))))
(loop (+ k 1)))
(else
(set! nl1 (- nl1 1))
(do ((is k (+ is 1))) ((>= is nl1))
(vector-set! l1 is (vector-ref l1 (+ is 1))))
(matrix-set! a (+ m 1) kp (fl+ (matrix-ref a (+ m 1) kp) 1.0))
(do ((i 0 (+ i 1))) ((= i (+ m 2)))
(matrix-set! a i kp (fl- (matrix-ref a i kp))))))))
((and (>= (vector-ref iposv (- ip 1)) (+ n m1))
(vector-ref l3 (- (vector-ref iposv (- ip 1)) (+ m1 n))))
(vector-set! l3 (- (vector-ref iposv (- ip 1)) (+ m1 n)) #f)
(matrix-set! a (+ m 1) kp (fl+ (matrix-ref a (+ m 1) kp) 1.0))
(do ((i 0 (+ i 1))) ((= i (+ m 2)))
(matrix-set! a i kp (fl- (matrix-ref a i kp))))))
(let ((t (vector-ref izrov (- kp 1))))
(vector-set! izrov (- kp 1) (vector-ref iposv (- ip 1)))
(vector-set! iposv (- ip 1) t))
(loop))))))
(and pass2?
(let loop ()
(simp1 0 #f)
(cond
((flpositive? bmax)
(simp2)
(cond ((zero? ip) #t)
(else (simp3 #f)
(let ((t (vector-ref izrov (- kp 1))))
(vector-set! izrov (- kp 1) (vector-ref iposv (- ip 1)))
(vector-set! iposv (- ip 1) t))
(loop))))
(else (list iposv izrov)))))))
(define (test)
(simplex (vector (vector 0.0 1.0 1.0 3.0 -0.5)
(vector 740.0 -1.0 0.0 -2.0 0.0)
(vector 0.0 0.0 -2.0 0.0 7.0)
(vector 0.5 0.0 -1.0 1.0 -2.0)
(vector 9.0 -1.0 -1.0 -1.0 -1.0)
(vector 0.0 0.0 0.0 0.0 0.0))
2 1 1))
(define (main . args)
(run-benchmark
"simplex"
simplex-iters
(lambda (result)
(equal? result '(#(4 1 3 2) #(0 5 7 6))))
(lambda () (lambda () (test))))))
|