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Problem with passing scalars from a field to an array

Dear Foamers,

I have this bug that I can't figure out! Three scalar fields are read from a dictionary:

Code:

// Override the Ux and Uy Gains

        OverrideFreq        

        (0.1   0.2    0.3    0.4     0.5);

        GainUx

        (5 5 6 7  8);

        GainUy

        (6 6 6 9 3);

Then values of scalars from the field are passed to a dynamic array using:

Code:

        Info << "Freq =  "<<filterFreqs_[i] << endl;

        forAll(OverrideFreq, fi)

          {

            Info << (OverrideFreq[fi])<< endl ;

            if (double(OverrideFreq[fi]) == double(filterFreqs_ [i]))

              {

                realGainUx_[i] = GainUx[fi];

                realGainUy_[i] = GainUy[fi]; 

                Info << " Condition Met : " << GainUx[fi] << "     " << GainUy[fi] << endl;

              }

          }     

        Info << "Real Gain Ux  =  " << realGainUx_[i] << "    Freq = " <<  filterFreqs_[i] << endl;

I get the result:

Code:

Freq =  0.1

0.1

 Condition Met : 5     6

0.2

0.3

0.4

0.5

Real Gain Ux  =  5    Freq = 0.1

Freq =  0.2

0.1

0.2

 Condition Met : 5     6

0.3

0.4

0.5

Real Gain Ux  =  5    Freq = 0.2

Freq =  0.3

0.1

0.2

0.3

0.4

0.5

Real Gain Ux  =  0    Freq = 0.3

Freq =  0.4

0.1

0.2

0.3

0.4

 Condition Met : 7     9

0.5

Real Gain Ux  =  7    Freq = 0.4

Freq =  0.5

0.1

0.2

0.3

0.4

0.5

 Condition Met : 8     3

Real Gain Ux  =  8    Freq = 0.5

For some reason, the 0.3 frequency is not recognized as a condition met!!!!
I fail to see what may be the problem!

Best regards,
Hisham

Info is probably formatting away the extra decimals. You are comparing double precision float numbers and you want an exact match? Try instead to take a difference:

Code:

// instead of:

if (double(OverrideFreq[fi]) == double(filterFreqs_ [i]))

// use:

if

(

    (double(OverrideFreq[fi]) - double(filterFreqs_[i]))

  < SMALL // or something even smaller - but not VSMALL

)

Hi David,

This solved it. Thanks a lot.

just to complete the picture:

Code:

if (abs(value-value)<tolerance)

{ // code.....}

Regards,
Hisham

Right... forgot about the absolute value. I'd suggest using OpenFOAM's built-in mag() function instead of abs()... just because I think it is more "type-safe"...