X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;ds=sidebyside;f=help%2Fhtml%2Fcalculations%2Fpca.html;h=2e5c16b33b0db72d068af81edc2717007d748c39;hb=91cb798a47b512b0ac3792fd3a84f2c5bd3c7218;hp=e824d7d41e45154b3e11b477f2f50af2148ec370;hpb=998ae297436877c6086f657e0a02c376cb5eb4dd;p=jalview.git diff --git a/help/html/calculations/pca.html b/help/html/calculations/pca.html index e824d7d..2e5c16b 100755 --- a/help/html/calculations/pca.html +++ b/help/html/calculations/pca.html @@ -11,12 +11,12 @@ sequences tend to lie near each other in the space.
usually because the JVM has run out of memory. The next release of Jalview release will execute this calculation through a web service.Principal components analysis is a technique for examining the -structure of complex datasets. The components are a set of dimensions -formed from the measured values in the dataset, and the principle +structure of complex data sets. The components are a set of dimensions +formed from the measured values in the data set, and the principle component is the one with the greatest magnitude, or length. The sets of measurements that differ the most should lie at either end of this principle axis, and the other axes correspond to less extreme -patterns of variation in the dataset. +patterns of variation in the data set.
In this case, the components are generated by an eigenvector @@ -25,25 +25,24 @@ each aligned position between each pair of sequences. The basic method is described in the paper by G. Casari, C. Sander and A. Valencia. Structural Biology volume 2, no. 2, February 1995 (pubmed) - and implemented at the SeqSpace server (http://industry.ebi.ac.uk/SeqSpace) at the EBI. + and implemented at the SeqSpace server at the EBI.
-The PCA Viewer
+The PCA Viewer
This is an interactive display of the sequences positioned within the similarity space. The colour of each sequence point is the same - as the sequence group coloring, white if no colour has been + as the sequence group colours, white if no colour has been defined for the sequence, and green if the sequence is part of a the currently selected group.
The 3d view can be rotated by dragging the mouse with the left mouse button pressed. The view can also be zoomed in and out with the up and down arrow - keys.
+ keys.A tool tip gives the sequence ID corresponding to a point in the space, and clicking a point toggles the selection of the - corresponding sequence in the alignment window. Rectanglar region - based selection is also possible, by holding the 's' key whilst + corresponding sequence in the alignment window. Rectangular region + based selection is also possible, by holding the 'S' key whilst left-clicking and dragging the mouse over the display.
Initially, the display shows the first three components of the