Re: [TRNSYS-users] Float error on squaring

[David Bradley <bradley@tess-inc.com>]

Henk,
 I tried to reproduce this error in both TRNSYS 15 and TRNSYS 16 using:

EQUATIONS 3
Var1 = TIME
Var2 = 24-TIME
Error = (Var1-Var2)^2

and was not able to get the floating point error that you report. Could you 
please send me an example in which the floating point occurs?
Thanks
  David


At 03:25 2/15/2006, henkwitte wrote:
> Hello,
>
> When I try to calculate in an equation the square of a difference of two 
> variables in TRNSYS 15 like:
>
> (value_var_1 - value_var_2)^2
>
> A floating point error is generated when the difference is or becomes zero.
>
> (value_var_1 - value_var_2) * (value_var_1 - value_var_2) does work 
> without problems
>
> Is this a known problem?
>
> If I just create an static equation with 0^2 it does not generate the 
> error, so it could be an underflow problem on the variables.
> Is there a round or MIN function in the equation of TRNSYS?
>
> Thanks
>
> Henk WItte
>
>
> Groenholland b.v.
> Valschermkade 26
> 1059 CD Amsterdam
> The Netherlands
>
> Tel.: +31 (0)20 - 6159050
> Fax:+31 (0)20 - 6177082
>
> mobiel: 0628176535
>
> http://www.groenholland.nl
>
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