fem_check_abc_la.f90 running
 solve a1(x,y) uxx(x,y) + b1(x,y) uxy(x,y) + c1(x,y) uyy(x,y) +
      d1(x,y) ux(x,y)  + e1(x,y) uy(x,y)  + f1(x,y) u(x,y) = c(x,y)
 boundary conditions computed using u(x)
 analytic solution may be given by u(x) ifcheck>0
 Gauss-Legendre integration used
  
 xmin=  -1.0000000000000000 , ymin =  -1.0000000000000000
 xmax=   1.0000000000000000 , ymax =   1.0000000000000000
 nx= 6 , ny = 5
 x grid and analytic solution, at ymin
 i= 1 , Ua(  -1.0000000000000000 )= -10.0000000000000000
 i= 2 , Ua(  -0.6000000000000000 )=  -5.2959999999999994
 i= 3 , Ua(  -0.2000000000000000 )=  -2.1280000000000001
 i= 4 , Ua(   0.2000000000000002 )=  -0.1119999999999983
 i= 5 , Ua(   0.6000000000000001 )=   1.1360000000000010
 i= 6 , Ua(   1.0000000000000000 )=   2.0000000000000000
  
 y grid and analytic solution, at xmin
 ii= 1 , Ua(  -1.0000000000000000 )= -10.0000000000000000
 ii= 2 , Ua(  -0.5000000000000000 )=  -2.7500000000000000
 ii= 3 , Ua(  0.0000000000000000E+000 )=   1.0000000000000000
 ii= 4 , Ua(   0.5000000000000000 )=   2.7500000000000000
 ii= 5 , Ua(   1.0000000000000000 )=   4.0000000000000000
  
solution at i=1, x=-1.000, ii=1, y=-1.000 is -10.000
solution at i=1, x=-1.000, ii=2, y=-0.500 is  -2.750
solution at i=1, x=-1.000, ii=3, y= 0.000 is   1.000
solution at i=1, x=-1.000, ii=4, y= 0.500 is   2.750
solution at i=1, x=-1.000, ii=5, y= 1.000 is   4.000
solution at i=2, x=-0.600, ii=1, y=-1.000 is  -5.296
solution at i=2, x=-0.600, ii=2, y=-0.500 is   0.794
solution at i=2, x=-0.600, ii=3, y= 0.000 is   4.184
solution at i=2, x=-0.600, ii=4, y= 0.500 is   6.374
solution at i=2, x=-0.600, ii=5, y= 1.000 is   8.864
solution at i=3, x=-0.200, ii=1, y=-1.000 is  -2.128
solution at i=3, x=-0.200, ii=2, y=-0.500 is   3.282
solution at i=3, x=-0.200, ii=3, y= 0.000 is   6.792
solution at i=3, x=-0.200, ii=4, y= 0.500 is   9.902
solution at i=3, x=-0.200, ii=5, y= 1.000 is  14.112
solution at i=4, x= 0.200, ii=1, y=-1.000 is  -0.112
solution at i=4, x= 0.200, ii=2, y=-0.500 is   5.098
solution at i=4, x= 0.200, ii=3, y= 0.000 is   9.208
solution at i=4, x= 0.200, ii=4, y= 0.500 is  13.718
solution at i=4, x= 0.200, ii=5, y= 1.000 is  20.128
solution at i=5, x= 0.600, ii=1, y=-1.000 is   1.136
solution at i=5, x= 0.600, ii=2, y=-0.500 is   6.626
solution at i=5, x= 0.600, ii=3, y= 0.000 is  11.816
solution at i=5, x= 0.600, ii=4, y= 0.500 is  18.206
solution at i=5, x= 0.600, ii=5, y= 1.000 is  27.296
solution at i=6, x= 1.000, ii=1, y=-1.000 is   2.000
solution at i=6, x= 1.000, ii=2, y=-0.500 is   8.250
solution at i=6, x= 1.000, ii=3, y= 0.000 is  15.000
solution at i=6, x= 1.000, ii=4, y= 0.500 is  23.750
solution at i=6, x= 1.000, ii=5, y= 1.000 is  36.000
boundary i=1, x=-1.000, ii=1, y=-1.000 is  -10.00000
boundary i=1, x=-1.000, ii=5, y= 1.000 is    4.00000
boundary i=2, x=-0.600, ii=1, y=-1.000 is   -5.29600
boundary i=2, x=-0.600, ii=5, y= 1.000 is    8.86400
boundary i=3, x=-0.200, ii=1, y=-1.000 is   -2.12800
boundary i=3, x=-0.200, ii=5, y= 1.000 is   14.11200
boundary i=4, x= 0.200, ii=1, y=-1.000 is   -0.11200
boundary i=4, x= 0.200, ii=5, y= 1.000 is   20.12800
boundary i=5, x= 0.600, ii=1, y=-1.000 is    1.13600
boundary i=5, x= 0.600, ii=5, y= 1.000 is   27.29600
boundary i=6, x= 1.000, ii=1, y=-1.000 is    2.00000
boundary i=6, x= 1.000, ii=5, y= 1.000 is   36.00000
boundary i=1, x=-1.000, ii=1, y=-1.000 is  -10.00000
boundary i=6, x= 1.000, ii=1, y=-1.000 is    2.00000
boundary i=1, x=-1.000, ii=2, y=-0.500 is   -2.75000
boundary i=6, x= 1.000, ii=2, y=-0.500 is    8.25000
boundary i=1, x=-1.000, ii=3, y= 0.000 is    1.00000
boundary i=6, x= 1.000, ii=3, y= 0.000 is   15.00000
boundary i=1, x=-1.000, ii=4, y= 0.500 is    2.75000
boundary i=6, x= 1.000, ii=4, y= 0.500 is   23.75000
boundary i=1, x=-1.000, ii=5, y= 1.000 is    4.00000
boundary i=6, x= 1.000, ii=5, y= 1.000 is   36.00000
 calling gaulegf npx= 48
 calling gaulegf npy= 48
 compute stiffness matrix
 ug computed Galerkin, Ua analytic, error
ug(1,1)=*******, Ua=*******, err= -0.1421085E-13
ug(1,2)=-2.7500, Ua=-2.7500, err=  0.1776357E-14
ug(1,3)= 1.0000, Ua= 1.0000, err=  0.1154632E-13
ug(1,4)= 2.7500, Ua= 2.7500, err=  0.0000000E+00
ug(1,5)= 4.0000, Ua= 4.0000, err=  0.0000000E+00
ug(2,1)=-5.2960, Ua=-5.2960, err=  0.5329071E-14
ug(2,2)= 0.7940, Ua= 0.7940, err=  0.4640732E-13
ug(2,3)= 4.1840, Ua= 4.1840, err=  0.5773160E-13
ug(2,4)= 6.3740, Ua= 6.3740, err=  0.4263256E-13
ug(2,5)= 8.8640, Ua= 8.8640, err=  0.5329071E-14
ug(3,1)=-2.1280, Ua=-2.1280, err= -0.7993606E-14
ug(3,2)= 3.2820, Ua= 3.2820, err=  0.9681145E-13
ug(3,3)= 6.7920, Ua= 6.7920, err=  0.1669775E-12
ug(3,4)= 9.9020, Ua= 9.9020, err=  0.1438849E-12
ug(3,5)=14.1120, Ua=14.1120, err= -0.5329071E-14
ug(4,1)=-0.1120, Ua=-0.1120, err=  0.0000000E+00
ug(4,2)= 5.0980, Ua= 5.0980, err=  0.3730349E-13
ug(4,3)= 9.2080, Ua= 9.2080, err=  0.1261213E-12
ug(4,4)=13.7180, Ua=13.7180, err=  0.1101341E-12
ug(4,5)=20.1280, Ua=20.1280, err=  0.7105427E-14
ug(5,1)= 1.1360, Ua= 1.1360, err= -0.8881784E-15
ug(5,2)= 6.6260, Ua= 6.6260, err= -0.2664535E-14
ug(5,3)=11.8160, Ua=11.8160, err= -0.1243450E-13
ug(5,4)=18.2060, Ua=18.2060, err= -0.2131628E-13
ug(5,5)=27.2960, Ua=27.2960, err=  0.0000000E+00
ug(6,1)= 2.0000, Ua= 2.0000, err=  0.0000000E+00
ug(6,2)= 8.2500, Ua= 8.2500, err=  0.0000000E+00
ug(6,3)=15.0000, Ua=15.0000, err=  0.0000000E+00
ug(6,4)=23.7500, Ua=23.7500, err=  0.0000000E+00
ug(6,5)=36.0000, Ua=36.0000, err=  0.0000000E+00
            maxerr=   1.6697754290362354E-13 , avgerr=   3.0797586703101840E-14
 end fem_check_abc_la.f90