diff toolboxes/FullBNT-1.0.7/docs/cellarray.html @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
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+++ b/toolboxes/FullBNT-1.0.7/docs/cellarray.html	Tue Feb 10 15:05:51 2015 +0000
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+Cell arrays are a little tricky in Matlab.
+Consider this example.
+
+C=num2cell(rand(2,3))
+C = 
+    [0.4565]    [0.8214]    [0.6154]
+    [0.0185]    [0.4447]    [0.7919]
+
+C{1,2}  % this is the contents of this cell (could be a vector or a string)
+ans =
+    0.8214
+
+C{1:2,2} % this is the contents of these cells - returns multiple
+answers!
+ans =
+    0.8214
+ans =
+    0.4447
+
+A = C(1:2,2)  % this is a slice of the cell array
+ans = 
+    [0.8214]
+    [0.4447]
+
+A{1}  % A is itself a cell array
+ans =
+    0.8214
+
+
+
+>> C(1:2,2)=0 % can't assign a scalar to a cell array
+C(1:2,2)=0
+??? Conversion to cell from double is not possible.
+
+
+>> C(1:2,2)={0;0} % can assign a cell array to a cell array
+C(1:2,2)={0;0}
+C = 
+    [0.4565]    [0]    [0.6154]
+    [0.0185]    [0]    [0.7919]
+
+
+BTW, I use cell arrays for evidence for 2 reasons:
+
+1. [] indicates missing values
+2. it can easily represent vector-valued nodes
+
+The following example  makes this clear
+
+C{1,1} = []
+C{2,1} = rand(3,1)
+
+C = 
+              []    [0]    [0.6154]
+    [3x1 double]    [0]    [0.7919]
+
+
+Hope this helps,
+Kevin