gcc/testsuite/gfortran.dg/bessel_6.f90

   1 ! { dg-add-options ieee }
   2 !
   3 ! PR fortran/36158
   4 ! PR fortran/33197
   5 !
   6 ! Run-time tests for transformations BESSEL_JN
   7 !
   8 implicit none
   9 real,parameter :: values(*) = [0.0, 0.5, 1.0, 0.9, 1.8,2.0,3.0,4.0,4.25,8.0,34.53, 475.78]
  10 real,parameter :: myeps(size(values)) = epsilon(0.0) &
  11                   * [2, 7, 5, 6, 9, 12, 12, 7, 7, 8, 98, 15 ]
  12 ! The following is sufficient for me - the values above are a bit
  13 ! more tolerant
  14 !                  * [0, 5, 3, 4, 6, 7, 7, 5, 5, 6, 66, 4 ]
  15 integer,parameter :: mymax(size(values)) =  &
  16                  [100, 17, 23, 21, 27, 28, 32, 35, 31, 41, 47, 37 ]
  17 integer, parameter :: Nmax = 100
  18 real :: rec(0:Nmax), lib(0:Nmax)
  19 integer :: i
  20
  21 do i = 1, ubound(values,dim=1)
  22   call compare(mymax(i), values(i), myeps(i))
  23 end do
  24
  25 contains
  26
  27 subroutine compare(mymax, X, myeps)
  28
  29 integer :: i, nit, mymax
  30 real X, myeps, myeps2
  31
  32 rec(0:mymax) = BESSEL_JN(0, mymax, X)
  33 lib(0:mymax) = [ (BESSEL_JN(i, X), i=0,mymax) ]
  34
  35 !print *, 'YN for X = ', X, ' -- Epsilon = ',epsilon(x)
  36 do i = 0, mymax
  37 !  print '(i2,2e17.9,e12.2,f18.10,2l3)', i, rec(i), lib(i), &
  38 !        rec(i)-lib(i),           ((rec(i)-lib(i))/rec(i))/epsilon(x), &
  39 !        rec(i) == lib(i), abs((rec(i)-lib(i))/rec(i)) < myeps
  40 if (rec(i) == lib(i)) CYCLE
  41 if (abs((rec(i)-lib(i))/rec(i)) > myeps) &
  42   STOP 1
  43 end do
  44
  45 end
  46 end