dKdt.f File Reference

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Functions/Subroutines
subroutine	dkdt (x, u, uprime, rpar, ipar)

Function/Subroutine Documentation

dkdt()

subroutine dkdt	(	real*8	x,
		real*8, dimension(1)	u,
		real*8, dimension(1)	uprime,
		real*8, dimension(*)	rpar,
		integer	ipar
	)

!     
      implicit none
      integer ipar
      real*8 x,u(1),uprime(1),rpar(*),zk0,phi,tup,
     &     xflow,pup,f1_x,k_x,lambda1,df1dk,rurd,f_k,kup
!
      external f_k
!
!     defining the parameters
      phi=rpar(1)
      lambda1=rpar(2)
      zk0=rpar(3)
      pup=rpar(4)
      tup=rpar(5)
      rurd=rpar(6)
      xflow=rpar(7)
      kup=rpar(8)
!     
!     find K(X) for the given x

      k_x=f_k(x,phi,lambda1,zk0,pup,tup,rurd,xflow,kup)
!
      k_x=dsqrt(k_x/x)
!
!     f1_x
      f1_x= (zk0*k_x)**(7.d0/4.d0)
     &     -(1-k_x)/dabs(1-k_x)*dabs(1-k_x)**(7d0*4d0)
!     
!     df1dK
      df1dk=7d0/4d0*zk0**(7d0/4d0)*k_x**(3.d0/4.d0)
     &     +7d0/4d0*dabs(1-k_x)**(3.d0/4.d0)
!     
!     
      uprime(1)=-0.8d0*x**1.6d0*lambda1*pup**(0.8d0)
     &     /(xflow*tup**1.8d0)*f1_x+u(1)
     &     *(lambda1*x**1.6d0*pup**0.8d0/(xflow*tup**0.8d0)
     &     *df1dk-2/x)
!     
      return
!