Incorrect floating-point numbers in sample model

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Robert Muetzelfeldt
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Joined: Sun Jan 08, 2012 7:20 pm
Location: Edinburgh, Scotland, UK
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Incorrect floating-point numbers in sample model

Post by Robert Muetzelfeldt » Tue Dec 15, 2015 4:11 pm

The XMILE spec states that floating-point numbers should conform to IEEE 754. This specifies that numbers should not begin with a leading decimal point.

However, the set of sample models for the spec includes one model ( lynx-hares.xml ) which has values which do begin with a leading decimal point, as shown in this extract:

Code: Select all

. . . . .
      <aux name="lynx_death_fraction">
        <eqn>hare_density</eqn>
        <gf>
          <xscale min="0" max="100" />
          <yscale min="0" max="1" />
          <ypts>.94,.66,.4,.35,.3,.25,.2,.15,.1,.07,.05</ypts>
        </gf>
      </aux>
. . . . .
This model validates OK, because the values are not represented individually, but rather are a single text value for the <ypts> element.

The immediate need is to fix values in the sample model, and any other models which include a lookup.

A better solution is to change the spec to list the values individually, so that they can be validated against the Schema, like:

Code: Select all

. . . . .
    <ypts>
         <ypt>0.94</ypt>
         <ypt>0.66</ypt>
         . . . . .
    </ypts>
. . . . . 
Robert

Karim Chichakly
Posts: 46
Joined: Fri Apr 10, 2009 11:52 am

Re: Incorrect floating-point numbers in sample model

Post by Karim Chichakly » Mon Dec 21, 2015 3:46 pm

The intention of IEEE 754 compatibility was for the behavior of operations, not the format of floating point numbers as text. The spec clearly shows the BNF for floating point numbers in Section 3.2.1, along with examples. Leading decimals are allowed.

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