I am trying to write a function which has a scalar input but an array output.
My example is:
Ts(theta) = reshape((/ dcos(theta)**2.d0, dsin(theta)**2.d0, -dsin(2.d0*theta)/2.d0, &
dsin(theta)**2.d0, dcos(theta)**2.d0, dsin(2.d0*theta)/2.d0, &
dsin(2.d0*theta), -dsin(2.d0*theta), dcos(2.d0*theta) /), (/3,3/))
The Ts(theta) is read as a 1 dimensional array but I want an output as a 2 dimensional array.
Is this possible?
Of course
function Ts(theta)
real(rp) :: Ts(3,3)
real(rp),intent(in) :: theta
Ts = reshape((/ cos(theta)**2, sin(theta)**2, -sin(2*theta)/2, &
sin(theta)**2, cos(theta)**2, sin(2*theta)/2, &
sin(2*theta), -sin(2*theta), cos(2*theta) /), (/3,3/))
end function
where rp is the right kind constant for current real precision.
Remark: do not use specific functions as dsin and dcos, they are remnants of FORTRAN 66 and obsolete since FORTRAN 77.
Your syntax Ts(theta) = means you probably tried a statement function. They are obsolete also. I am not sure if they can be array-valued, you may try it.
contains section of the program. Second, you have to define rp if you want to use it. Say, integer,parameter :: rp = kind(1.d0)