Re: Slow performance gathering property data from fitted
- To: mathgroup at smc.vnet.net
- Subject: [mg101022] Re: [mg101013] Slow performance gathering property data from fitted
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Sun, 21 Jun 2009 07:05:22 -0400 (EDT)
- References: <200906200803.EAA16775@smc.vnet.net>
- Reply-to: drmajorbob at bigfoot.com
Did you do something equivalent to this?
data := Table[{3 + i + RandomReal[{-3, 7}],
i + RandomReal[{-2, 5}]}, {i, 1, 20}]
Timing[models = Array[LinearModelFit[data, x, x] &, 70000];]
{90.2283, Null}
Timing[rsquares = Through[models@"RSquared"];]
{40.3059, Null}
ListPlot@rsquares
Notice, the RSquare values came out faster than the model fitting.
Bobby
On Sat, 20 Jun 2009 03:03:15 -0500, Todd Allen <genesplicer28 at yahoo.com>
wrote:
>
> Hi All,
>
> During some recent research I asked Mathematica to calculate 70,000
> simple linear regression fits to 70,000 small datasets. This worked
> well and resulted in a list of 70,000 fitted model objects being
> finished in under 5 minutes.
>
> My next step was to collect the RSquared property for each of the
> 70,000 fits contained in the list, and Mathematica took over 3 hours to
> accomplish this. This seems horrendously slow simply to gather values
> from a list. Has anyone ran into a similar problem? Any suggestions
> how I might be able to significantly speed the gathering of properties
> from large lists of fitted model objects?
>
>
> The snippet of code I was using to gather the RSquared values is below:
>
> piedlrRsquared =
> Table[piedlrmodels[[i]]["RSquared"], {i, 1, Length[piedlrmodels]}] //
> Timing;
>
>
> Thanks for any advice you might have!
>
> Todd
>
>
>
--
DrMajorBob at bigfoot.com
- References:
- Slow performance gathering property data from fitted objects
- From: Todd Allen <genesplicer28@yahoo.com>
- Slow performance gathering property data from fitted objects