JAEA-Data/Code 2007-004 - Welcome to Research Group for ...

Record format of all members is common, although their contents differ. For example, the structure of
a member ‘TEST0000’ which has 100 real numbers and 50 integers is as follows.
LENG A(1) A(2) . . . . . . . . A(100) N(1) N(2) . . . . . . . . N(50)
Here, ‘LENG’ is the total data length in word unit (one word = 4 byte), thus LENG=150 in this case.
Data of the member TEST0000 can be read by the following Fortran program.
C----------------------------------------------------------
DIMENSION A(100),N(50),WORK(200),IWORK(200)
EQUIVALENCE (WORK(1),IWORK(1))
OPEN(UNIT=1,FILE='TEST0000',FORM='UNFORMATTED,ACCESS=SEQUENTIAL)
READ(1) LENG, (WORK(I),I=1,LENG)
DO I=1,100
A(I)=WORK(I)
END DO
DO I=1,50
N(I)=IWORK(I+100)
END DO
CLOSE(UNIT=1)
C----------------------------------------------------------
Since the SRAC code treats so many members, frequent opening and closing of members causes
much execution time. To reduce it, virtual PDS files on the core memory are used during the execution.
The members once read by the SRAC code are kept in the virtual PDS files, and after that, the data
access to the members is done on the memory. When the total amount of data exceeds the memory
capacity secured for the virtual PDS, the data access via virtual PDS is automatically switched to the
direct access to the actual PDS. Details on the contents of each member in PDS files and the rule of
member name in the SRAC code are described in Sect.3.1.
1.5 Definition of Energy Range
The processing of making the Public Library is dependent on neutron energy range. In the
SRAC calculation, the shape of the asymptotic spectrum to collapse the cross-sections of the Public
Library into those of the User Library depends on the energy range. Moreover, spatial sub-division for
the flux distribution is, in general, changeable by the energy range. Here, the energy range is defined
as follows.
10