error on UMAT with--> implicit real*8(a-h,o-z)

[nazman]

hi everyone, i try to simulate the UMAT subroutine in Abaqus 6.4-1 and the codes was written in Compaq Visual fortran. However, i keep on receiving this message when i submitted the job;

ABAQUS JOB Nazman3_umat8Jan08
ABAQUS version 6.4-1
Begin Compiling ABAQUS/Standard User Subroutines
1/9/2008 12:19:33 PM
Subroutine remodelling2.for
Subroutine remodelling2.for(29) : Error: The same letter must not appear as a single letter or be included in a range of letters more than once in all IMPLICIT statements in a scoping unit.
Implicit real*8(a-h,o-z)
--------^
ABAQUS Error: Problem during compilation - C:\abaqusjob\Nazman\Test UMAT 1\Subroutine remodelling2.for
ABAQUS/Analysis exited with errors


Can anyone help me on this? what is the real problem when i write Implicit real*8(a-h,o-z) ?
Thanx for your cooperation.

Regards,
Nazman, Malaysia.

[Jorgen]

Do you already include:
INCLUDE 'ABA_PARAM.INC'

or
include 'vaba_param.inc'

Then those files already have an IMPLICIT statement.

- Jorgen

[nazman]

thanx Dr, actually i already put those statement in my codes, then i put also implicit real*8(a-h,o-z).....when i erase implicit real*8(a-h,o-z) from the codes, error because of linking will appear. really need your help. thank Dr.

nazman

[Jorgen]

I think you have two choices:

(1) Use the "include 'aba_param.inc'" statement, and do not write your own "implicit" statement.

(2) Do not use either of those statements, and instead declare all your variables.

I much prefer the second option! See this write-up (http://polymerfem.com/forums/showthread.php?t=582).

- Jorgen