********>Bugfix 21:
Author: Dave Case, (originally from Ilyas)

Date:   June 2, 2009

Programs: molsurf

Description: A buried atom assertion can be triggered by numerical noise; this
             patch avoids that

Use this patch to update amber10/src/mm_pbsa/molsurf.c

------------------------------------------------------------------------------
*** molsurf.c	2 Jun 2008 22:15:47 -0000	10.1
--- molsurf.c	17 Sep 2008 10:47:50 -0000	10.2
***************
*** 1030,1036 ****
    POINT t_ij, t_ik, t_diff;
    REAL_T b_factor, h_ijk, xtest;
    REAL_T w_ijk, w_sin, r_pk2;
!   REAL_T sarg1, sarg2;
    POINT b_ijk, r_ib;
    void cross ();
    int i;
--- 1030,1036 ----
    POINT t_ij, t_ik, t_diff;
    REAL_T b_factor, h_ijk, xtest;
    REAL_T w_ijk, w_sin, r_pk2;
!   REAL_T sarg1, sarg2, check1, check2, check3, check4;
    POINT b_ijk, r_ib;
    void cross ();
    int i;
***************
*** 1050,1056 ****
    }
  
    sarg1 = (ai->rad + aj->rad + probe_diam) * (ai->rad + aj->rad +
! 		probe_diam) - d_ij * d_ij;
    sarg2 = d_ij * d_ij - (ai->rad - aj->rad) * (ai->rad - aj->rad);
    assert( sarg1 >= 0.0 );
    assert( sarg2 >= 0.0 );
--- 1050,1065 ----
    }
  
    sarg1 = (ai->rad + aj->rad + probe_diam) * (ai->rad + aj->rad +
!     probe_diam) - d_ij * d_ij;
!      /* For rounding to 6 decimal points in case sarg1 < 0 */
!   if(sarg1 < 0){
!      check1 = sarg1;
!      check2 = 0;
!      check3 = fabs(modf( check1 * 1000000, &check2));
!      check4 = (floor(check1 * 1000000) + (check3 < 0.5 ? 1 : 0 ))/1000000;
!      sarg1 = check4;
!   }
! 
    sarg2 = d_ij * d_ij - (ai->rad - aj->rad) * (ai->rad - aj->rad);
    assert( sarg1 >= 0.0 );
    assert( sarg2 >= 0.0 );
------------------------------------------------------------------------------
Temporary Workarounds: None