Confused by DATA

[seagullsarebeautiful]

Hi,

I am translation some Fortran to Java and would appreciate some help to understand what the DATA below means.


DOUBLE PRECISION FUNCTION BESFJ1(X)

DOUBLE PRECISION X
DOUBLE PRECISION SRNAME

DATA SRNAME /8H BESFJ1 /

Is there now some equivalence between BESFJ1 and SRNAME ? what does the 8H signify ?

thanks
David

 

[FJacq]

Today, a Fortran programmer would write :

CHARACTER(8) :: SRNAME=' BESFJ1 '

! please notice the spaces at first and last positions...

8H means that 8 characters (Hollerith form). But this is a very old form (Fortran 66 => 50 years ago), when Fortran did not have character variables, i.e. when it was "normal" to store characters within real or integer values.

François Jacq

 

[seagullsarebeautiful]

Thank you François,

I might never have guessed that it was a String being loaded into the storage of a double.

On reflection the identifier SRNAME was a good hint that something stringy was going on but I was thrown by the type DOUBLE PRECISION and was convinced that something strangely numerical was happening with the function address.

This old fortran is full of stuff I will try to google but more questions are inevitable so please stay tuned.

David

 

[xwb]

Using doubles to store characters is a very old style of programming - you've probably gotten it from a Fortran IV (F66) program from a 16-bit mini. The later versions of Fortran (since F77) have character handling. It would be better if you used the character handling features.