Creating and editing a data set
1. Click on the working tab to activate the working data form.
File | Exit
is selected, if a data set has been altered in any way, but not
saved, you will be asked if you would like to save the data.
Maximum size of the data set and computation speed
In CAP 3.0 new array handling technology has been introduced to enable the
analysis of very large data sets.
Theoretically, the size of the input data matrix is unlimited although, in practice,
the memory resources of the PC is usually the limiting factor. In tests we have run
CAP with a data array of 5000 species x 5000 samples without difficulty.
Because of its unusual computational requirements, which involves the
generation of new data items in the form of pseudospecies, TWINSPAN is more
demanding in memory usage. The maximum size of the data set whilst running
TWINSPAN is therefore likely to be slightly smaller than for the other multivariate
methods. It should still easily be sufficient for most users needs, however.
Our new approach to data handling means that on a reasonably modern PC,
most of the computation, even on very large data sets, can be completed within a
few seconds. All computations with data sets of up to 100 samples by 100
species are usually almost instantaneous.
If you do run into speed problems with very large data sets, it will generally be
improved if there are no other Windows applications running at the time.
Copyright 2004, PISCES CONSERVATION LTD