[Octave-bug-tracker] [bug #41461] cast to integer type incorrect

[Mike Sander]

URL:
  <http://savannah.gnu.org/bugs/?41461>

                 Summary: cast to integer type incorrect
                 Project: GNU Octave
            Submitted by: msander
            Submitted on: Wed 05 Feb 2014 02:44:26 AM GMT
                Category: Octave Function
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Incorrect Result
                  Status: None
             Assigned to: None
         Originator Name: mike sander
        Originator Email: 
             Open/Closed: Open
         Discussion Lock: Any
                 Release: dev
        Operating System: Any

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Details:


octave:1> x=int8(-128)
x = -128
octave:2> z=char(x)
warning: range error for conversion to character value
error: value on right hand side of assignment is undefined


I believe this should return 0.   This assumes char maps to unsigned 8 bit
type.



octave:2> x=256
x =  256
octave:3> z=char(x)
warning: range error for conversion to character value
z = 
octave:4> single(z)  # to show value
ans = 0


this should return 255.

The attached patch (cast_integer01.diff) has a proposed fix for integer types.
 I am open to comments/suggestions.   Specifically is use of
std::numeric_limits appropriate in this context?

NB. bug #38956 is related, but only considers +ve portion, not the undefined
value.



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File Attachments:


-------------------------------------------------------
Date: Wed 05 Feb 2014 02:44:26 AM GMT  Name: cast_integer01.diff  Size: 1kB  
By: msander

<http://savannah.gnu.org/bugs/download.php?file_id=30460>

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