Re: problem with fltk

[marco atzeri]

On 12/15/2011 11:45 AM, Michael Goffioul wrote:
> 2011/12/15 jacques.beilin<address@hidden>:
> > Hi,
> >
> > Here are the scripts. The script compare_fltk_gnuplot.m loads the data and
> > creates the plots using the 2 backends.
> >
> > The columns in deltaXYZ.txt are : column 1 : Modified Julian Date, Columns
> > 2,3,4 : X,Y,Z
> >
> > I suppose I am doing something wrong but I cannot see what !
>
> I don't think you are. My first idea would be that the problem is due
> to rounding errors in OpenGL (which internally uses single floats, not
> double).
>
> Michael.

it is a rounding error.
all the data on the first column are very near

 5.51300201e+04 -2.02548504e-02 1.06003433e-02 2.65523735e-02
 5.51300208e+04 -2.34114490e-02 1.00998580e-02 3.53220068e-02
...
 5.51300889e+04 -6.01677597e-03 -5.80356270e-03 3.66309634e-02
 5.51300896e+04 -7.13784248e-03 -5.65697253e-03 3.21426634e-02


Jaques,
if from the original data you remove 55130, you will see the expected shape.

Regards
Marco