From Gerhard.Thallinger at tugraz.at  Sat May 13 12:54:10 2006
From: Gerhard.Thallinger at tugraz.at (Gerhard Thallinger)
Date: Sat, 13 May 2006 12:54:10 +0200
Subject: [Rd] str() with attr(*,
	"names") is extremely slow for long vectors
Message-ID: <000201c6767b$918bc8b0$0400a8c0@mobilix>

>>>>> "HenrikB" == Henrik Bengtsson (max 7Mb) <hb at stat.berkeley.edu> 
>>>>> on Fri, 5 May 2006 11:58:19 -0700 writes: 

  HenrikB> Hi,
  HenrikB> I noticed some time ago that, for instance, named vectors 
  HenrikB> that are really makes str() really slow when displaying the
  HenrikB> names attribute.

  HenrikB> I don't know exactly when this started, but it wasn't the   
  HenrikB> case say 1-2 years ago. Example (on a WinXP 1.8GHz): 

It got slower with R 2.3.0. Comparing str() for a big exprSet object
from the "Biobase" package I got the following numbers 
(system.time(str(anaexp)) on WinXP 1.8 GHz):

  R 2.2.0

    1. 14.64  0.13 14.90    NA    NA
    2.  4.33  0.09  4.43    NA    NA
    3.  4.20  0.15  4.38    NA    NA

  R 2.3.0

    1. 65.36  0.18 66.12    NA    NA
    2. 51.75  0.21 52.55    NA    NA
    3. 51.79  0.17 52.45    NA    NA


One can notice a considerable speed-up in the 2nd & 3rd call to str() 
in R 2.2.0, which is much less pronounced in R 2.3.0.
  
Hth 

Gerhard

------------------------------------------------------------------------
DI Gerhard Thallinger              E-mail:  Gerhard.Thallinger at tugraz.at
Institute for Genomics and Bioinformatics   Web: http://genome.tugraz.at
Graz University of Technology               Tel:        +43 316 873 5343
Petersgasse 14/V                            Fax:        +43 316 873 5340
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[Rd] str() with attr(*, "names") is extremely slow for long vectors
Gerhard Thallinger