Wireshark · Wireshark-dev: Re: [Wireshark-dev] Sorting floats?

["Maynard, Chris" <Christopher.Maynard@xxxxxxxxx>]

Title: Sorting floats?

Not knowing the test data which makes it fails, I can only suggest a couple of things:

 

First, why consider floats equal if their difference is less than some tolerance?  Why not just compare them and let the natural comparison dictate less than, equal or greater than?  i.e.,

 

if (f1 == f2)

    return 0;

if (f1 < f2)

    return -1;

return 1;

 

Also, is it possible that atof() is failing but that the error is not being detected and that is causing problems?  If so, try strtod() instead and add code to handle the errors?

 

- Chris

 

 

From: wireshark-dev-bounces@xxxxxxxxxxxxx [mailto:wireshark-dev-bounces@xxxxxxxxxxxxx] On Behalf Of Anders Broman
Sent: Tuesday, February 17, 2009 3:42 AM
To: Developer support list for Wireshark
Subject: [Wireshark-dev] Sorting floats?

 

Hi,
The following code in rtp_analysis.c
        case 4:
                f1=atof(text1);
                f2=atof(text2);
                if (fabs(f1-f2)<0.0000005)
                        return 0;
                if (f1<f2)
                        return -1;
                return 1;
Is used to sort floats but it seems not to give the right result. Does any one know how to fix it?

Regards
Anders

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