1! 2! CalculiX - A 3-dimensional finite element program 3! Copyright (C) 1998-2021 Guido Dhondt 4! 5! This program is free software; you can redistribute it and/or 6! modify it under the terms of the GNU General Public License as 7! published by the Free Software Foundation(version 2); 8! 9! 10! This program is distributed in the hope that it will be useful, 11! but WITHOUT ANY WARRANTY; without even the implied warranty of 12! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13! GNU General Public License for more details. 14! 15! You should have received a copy of the GNU General Public License 16! along with this program; if not, write to the Free Software 17! Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18! 19! d{K(X)}/dX 20! 21! author: Yannick Muller 22! 23 subroutine dKdX(x,u,uprime,rpar,ipar) 24! 25 implicit none 26 integer ipar 27 real*8 x,u(1),uprime(1),rpar(*),zk0,phi 28! 29! defining the parameters 30 phi=rpar(1) 31 zk0=rpar(3) 32 33 uprime(1)=datan(1.d0)*0.315d0/(phi)*x**1.6d0* 34 & ((zk0*u(1))**1.75d0- 35 & (dabs(1.d0-u(1)))**1.75d0*(1.d0-u(1))/dabs(1.d0-u(1))) 36 & -2.d0*u(1)/x 37! 38 return 39! 40 end 41! 42