Re: Floating Point Question

[bmorris@xxxxxxxxxx]

Nelson, do you mean you have an alpha field with a value like "3.5E7"
or "12.345"?  If so, try the 'atof' function (A).  If you mean that you
have 8 bytes containing an actual floating point value, use a based 8F
variable, and set its basing pointer to the address of the char field (B).

----------------------------- A -----------------------------
H bnddir('QC2LE')
D float           s              8f
D atof            pr             8f   extproc('atof')
D   alpha                         *   value options(*string)
D charfld         s             10a   inz('.31416E1')

C                   eval      float = atof('123.45')
C                   eval      float = atof('4.5E72')
C                   eval      float = atof('73')
C                   eval      float = atof(%trim(charfld))
C                   seton

Debug session output after each eval:
  > EVAL float
    FLOAT =   1.234500000000E+002
  > EVAL float
    FLOAT =   4.500000000000E+072
  > EVAL float
    FLOAT =   7.300000000000E+001
  > EVAL float
    FLOAT =   3.141600000000E+000

----------------------------- B -----------------------------
If you mean that you have 8 bytes containing an actual floating point
value, use a based 8F variable, and set its basing pointer to the address
of the char field.

D floatVal        s              8f
D basedFloat      s              8f   based(pFloat)
D rec             s           1000a

 * Get the floating point value at offset "off" in field "rec"
 * into the float field "floatVal"
C                   eval     pFloat = %addr(rec) + off
C                   eval     floatVal = basedFloat
C                   seton

I'm guessing the second case is correct.  If so, I'd use this technique for
all the types, using a based data structure with a subfield starting at
position 1 for each possible type.  Set your basing pointer to the address
of the record + the offset, then just assign from one of the based subfields.

Barbara Morris

>Date: Wed, 11 Aug 1999 21:01:57 -0400
>From: "Nelson C. Smith" <ncsmith@gate.net>
>Subject: Re: Floating Point Question
>
>I have a procedure that substrings bytes out of file records based on =
>field types, sizes, location, etc defined in the system catalog.  The =
>target of the substring is a char field, of course.  With other fields, =
>I can do a movel into the proper data type, but Floating point is not =
>allowed on the movel opcode. How can I get the data in the alpha field =
>into a floating point field? Is there any way to "cast" the subst =
>results into something other than an alpha field?


+---
| This is the Midrange System Mailing List!
| To submit a new message, send your mail to MIDRANGE-L@midrange.com.
| To subscribe to this list send email to MIDRANGE-L-SUB@midrange.com.
| To unsubscribe from this list send email to MIDRANGE-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---