<Example Program>

Program sum_example
    Real a(2,3)
    a = Reshape( (/2.,3.,5.,-1.,4.,-3./), (/2,3/))
    Print *, Sum(a)
    Print *, Sum(a,Dim=1)
    Print *, Sum(a,Dim=2)
    Print *, Sum(a,Mask=a>0)
End Program

Execution Results

  10.0000000
   5.0000000   4.0000000   1.0000000
  11.0000000  -1.0000000
  14.0000000