[Kst] [Bug 87018] New: fits to curves with different length X and Y vectors is incorrect.

[netterfield at astro.utoronto.ca]

------- You are receiving this mail because: -------
You are the assignee for the bug, or are watching the assignee.
      
http://bugs.kde.org/show_bug.cgi?id=87018      
           Summary: fits to curves with different length X and Y vectors is
                    incorrect.
           Product: kst
           Version: unspecified
          Platform: unspecified
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: NOR
         Component: general
        AssignedTo: kst kde org
        ReportedBy: netterfield astro utoronto ca


Version:           0.99-devel (using KDE 3.2 BRANCH >= 20040204, Mandrake Linux Cooker i586 - Cooker)
Compiler:          gcc version 3.3.2 (Mandrake Linux 10.0 3.3.2-6mdk)
OS:                Linux (i686) release 2.6.2-3mdk

-Create a curve where the X-vector length is different from the Y vector length
(eg, 5 frames of INDEX vs cos from dirfile_maker) and plot it.

select plot->rmb->fit-><curvename>

from the plot dialog, select a fit (eg, fit polynomial degree 3).

The fit is incorrect.

This is because the fits do not assume the curve rule that X[0]->Y[0] and X[xlen-1]->Y[ylen-1], and interpolate inbetween.