Initial commit

2016-02-03 18:52:05 +00:00
commit d40505e161
507 changed files with 91383 additions and 0 deletions
@@ -0,0 +1,44 @@
+      SUBROUTINE ratint(xa,ya,n,x,y,dy)
+      INTEGER n,NMAX
+      REAL dy,x,y,xa(n),ya(n),TINY
+      PARAMETER (NMAX=10,TINY=1.e-25)
+      INTEGER i,m,ns
+      REAL dd,h,hh,t,w,c(NMAX),d(NMAX)
+      ns=1
+      hh=abs(x-xa(1))
+      do 11 i=1,n
+        h=abs(x-xa(i))
+        if (h.eq.0.)then
+          y=ya(i)
+          dy=0.0
+          return
+        else if (h.lt.hh) then
+          ns=i
+          hh=h
+        endif
+        c(i)=ya(i)
+        d(i)=ya(i)+TINY
+11    continue
+      y=ya(ns)
+      ns=ns-1
+      do 13 m=1,n-1
+        do 12 i=1,n-m
+          w=c(i+1)-d(i)
+          h=xa(i+m)-x
+          t=(xa(i)-x)*d(i)/h
+          dd=t-c(i+1)
+          if(dd.eq.0.)pause 'failure in ratint'
+          dd=w/dd
+          d(i)=c(i+1)*dd
+          c(i)=t*dd
+12      continue
+        if (2*ns.lt.n-m)then
+          dy=c(ns+1)
+        else
+          dy=d(ns)
+          ns=ns-1
+        endif
+        y=y+dy
+13    continue
+      return
+      END