Re: [matplotlib-devel] Adding upper and lower limits to errorbar

[Paul B. <peb...@gm...>]

On 10/7/05, John Hunter <jdh...@ac...> wrote:
>
> >>>>> "Paul" =3D=3D Paul Barrett <peb...@gm...> writes:
>
> Paul> I have data that has error bars and upper limits. (Actually
> Paul> they are lower limits, since the Y axis is in stellar
> Paul> magnitudes and is inverted.) My suggestion is use a negative
> Paul> error value to indicate a limit in which case an arrow would
> Paul> be drawn, instead of an error bar. This feature would only
> Paul> apply to the case of asymmetric error bars and not to the
> Paul> symmetric case. I can produce a patch if this suggestion is
> Paul> agreeable.
>
> I certainly don't have a problem with this and would be happy to
> include these extensions to the errorbar function. I wonder if the
> arrow is the best indicator for a limit, though I can't think of a
> better one at the moment. Also, does this handle limits in either
> direction (up or down) as well as left to right?
>

Yes, a negative value for the upper error bar will indicate an upper limit
and vice versa for the lower error bar value. The same goes for left and
right limits.

Note that this enhancement will only affect asymmetric error bars and not
symmetric ones, since the latter case doesn't make much sense to me.

-- Paul