Initial commit

2016-02-03 18:52:05 +00:00
commit d40505e161
507 changed files with 91383 additions and 0 deletions
@@ -0,0 +1,64 @@
+      SUBROUTINE mnbrak(ax,bx,cx,fa,fb,fc,func)
+      REAL ax,bx,cx,fa,fb,fc,func,GOLD,GLIMIT,TINY
+      EXTERNAL func
+      PARAMETER (GOLD=1.618034, GLIMIT=100., TINY=1.e-20)
+      REAL dum,fu,q,r,u,ulim
+      fa=func(ax)
+      fb=func(bx)
+      if(fb.gt.fa)then
+        dum=ax
+        ax=bx
+        bx=dum
+        dum=fb
+        fb=fa
+        fa=dum
+      endif
+      cx=bx+GOLD*(bx-ax)
+      fc=func(cx)
+1     if(fb.ge.fc)then
+        r=(bx-ax)*(fb-fc)
+        q=(bx-cx)*(fb-fa)
+        u=bx-((bx-cx)*q-(bx-ax)*r)/(2.*sign(max(abs(q-r),TINY),q-r))
+        ulim=bx+GLIMIT*(cx-bx)
+        if((bx-u)*(u-cx).gt.0.)then
+          fu=func(u)
+          if(fu.lt.fc)then
+            ax=bx
+            fa=fb
+            bx=u
+            fb=fu
+            return
+          else if(fu.gt.fb)then
+            cx=u
+            fc=fu
+            return
+          endif
+          u=cx+GOLD*(cx-bx)
+          fu=func(u)
+        else if((cx-u)*(u-ulim).gt.0.)then
+          fu=func(u)
+          if(fu.lt.fc)then
+            bx=cx
+            cx=u
+            u=cx+GOLD*(cx-bx)
+            fb=fc
+            fc=fu
+            fu=func(u)
+          endif
+        else if((u-ulim)*(ulim-cx).ge.0.)then
+          u=ulim
+          fu=func(u)
+        else
+          u=cx+GOLD*(cx-bx)
+          fu=func(u)
+        endif
+        ax=bx
+        bx=cx
+        cx=u
+        fa=fb
+        fb=fc
+        fc=fu
+        goto 1
+      endif
+      return
+      END