Re: [find_orb] Find_Orb Wish List

Bill J Gray Apr 25, 2011

Hi Andrew,

> 1. Any chance that you could add the "uncertainty parameter" as defined
> by the MPC to the orbital solution?

Some small chance, at least. I've long thought Find_Orb should
provide uncertainties for orbital elements and ephemerides. With the
Monte Carlo and statistical ranging methods in place, it can look at
the distribution of those data and compute sigmas... which leads to the
U parameter without much trouble.

A few months ago, I also dug into the issues of computing uncertainties
from the covariance matrix, and have made at least a little progress on
that front.

> 2. Under "Make Ephemeris", would it be possible to have today's date in
> the "Start" window as the default, or at least have a push button to add
> today's date to the window with one click?

I've just implemented the latter. The version already posted already
allow one to enter, for example, "+0" to get the current time, or "-18h"
for eighteen hours ago, and so on; clicking on the new "Now" button will
just set the start time to "+0".

One slight issue with this is that "+0" means _right now_, not the
nearest or previous midnight. I've also just added a "round to nearest
step" checkbox. Click on that button, and an ephemeris run at
2011 April 25 16:44:13 UT would begin on 2011 April 25 00:00 UT (for a
one-day step size), or at 16:00 on that day (for a one-hour step size),
or at 16:44 (for a one-minute step size).

> 3. On the main page, is it possible to define a fixed-width font so that
> the display of the elements "line up" properly?

I tackled this quite a while ago, without success. But since then,
I've made the ephemerides box fixed-width... and it turns out that the same
trick works with the orbital elements box.

That's the good news. Bad news is that with a fixed-width font, the
elements are too wide to fit in the box. I may have to rearrange the main
Find_Orb dialog to accommodate a wider element display... which isn't a
bad idea; that dialog has "just grown" with new options, and a total
rearrangement is overdue anyway.

-- Bill