annotate general/funutils/fold.m @ 4:e44f49929e56
Adding reorganised general toolbox, now in several subdirectories.
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samer |
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Sat, 12 Jan 2013 19:21:22 +0000 |
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45aaf9b2d7b0 |
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1 function X=fold(fn,args)
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2 % fold - Fold combinator from functional programming
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3 %
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4 % This function applies an associative operator to a list of arguments,
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5 % as if the list was written out with the operator between consecutive
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6 % elements, eg fold(@plus,{1,2,3,4}) = 1+2+3+4.
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7 %
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8 % fold ::
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9 % (X,X->X) ~'associative binary operator',
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10 % {[N]->X} ~'list (cell array) of arguments (at least 2 elements)'
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11 % -> X.
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12
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13 if isempty(args), X=[]; else X=foldl(fn,args{1},args(2:end)); end
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