Initial commit

2016-02-03 18:52:05 +00:00
commit d40505e161
507 changed files with 91383 additions and 0 deletions
@@ -0,0 +1,38 @@
+      FUNCTION rtflsp(func,x1,x2,xacc)
+      INTEGER MAXIT
+      REAL rtflsp,x1,x2,xacc,func
+      EXTERNAL func
+      PARAMETER (MAXIT=30)
+      INTEGER j
+      REAL del,dx,f,fh,fl,swap,xh,xl
+      fl=func(x1)
+      fh=func(x2)
+      if(fl*fh.gt.0.) pause 'root must be bracketed in rtflsp'
+      if(fl.lt.0.)then
+        xl=x1
+        xh=x2
+      else
+        xl=x2
+        xh=x1
+        swap=fl
+        fl=fh
+        fh=swap
+      endif
+      dx=xh-xl
+      do 11 j=1,MAXIT
+        rtflsp=xl+dx*fl/(fl-fh)
+        f=func(rtflsp)
+        if(f.lt.0.) then
+          del=xl-rtflsp
+          xl=rtflsp
+          fl=f
+        else
+          del=xh-rtflsp
+          xh=rtflsp
+          fh=f
+        endif
+        dx=xh-xl
+        if(abs(del).lt.xacc.or.f.eq.0.)return
+11    continue
+      pause 'rtflsp exceed maximum iterations'
+      END