[Octave-bug-tracker] [bug #50278] Incorrect comparison due to numerical precision

[anonymous]

URL:
  <http://savannah.gnu.org/bugs/?50278>

                 Summary: Incorrect comparison due to numerical precision
                 Project: GNU Octave
            Submitted by: None
            Submitted on: Fri 10 Feb 2017 11:17:09 PM UTC
                Category: None
                Severity: 3 - Normal
                Priority: 5 - Normal
              Item Group: Incorrect Result
                  Status: None
             Assigned to: None
         Originator Name: 
        Originator Email: address@hidden
             Open/Closed: Open
         Discussion Lock: Any
                 Release: 4.2.0
        Operating System: Microsoft Windows

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Details:

The simple script below results in an error.  When k=4, t(4) = 0.3 but is not
<= 0.3 due to numerical precision. 


for k = 1:7
    t(k)=(k-1)*0.1; 
    if t(k) <= 0.3
        M(k) = 0;
    else
        M(k) = 2;
    end
end


Gives result:

>>t
t = 0.00000   0.10000   0.20000   0.30000   0.40000   0.50000   0.60000
>>M
M = 0   0   0   2   2   2   2
>>t(4) - 0.3
ans =   5.5511e-017


Octave 4.2.0 is configured for "x86_64-w64-minw32" running on Windows 10 Home,
Intel Core 17-7500U




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