comparison toolboxes/FullBNT-1.0.7/KPMtools/subv2indKPM.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function ndx = subv2indKPM(siz, subv)
+% SUBV2IND Like the built-in sub2ind, but the subscripts are given as row vectors.
+% ind = subv2ind(siz,subv)
+%
+% siz can be a row or column vector of size d.
+% subv should be a collection of N row vectors of size d.
+% ind will be of size N * 1.
+%
+% Example:
+% subv = [1 1 1;
+%         2 1 1;
+%         ...
+%         2 2 2];
+% subv2ind([2 2 2], subv) returns [1 2 ... 8]'
+% i.e., the leftmost digit toggles fastest.
+%
+% See also IND2SUBV.
+
+
+if isempty(subv)
+  ndx = [];
+  return;
+end
+
+if isempty(siz)
+  ndx = 1;
+  return;
+end
+
+[ncases ndims] = size(subv);
+
+%if length(siz) ~= ndims
+%  error('length of subscript vector and sizes must be equal');
+%end
+
+if all(siz==2)
+  %rbits = subv(:,end:-1:1)-1; % read from right to left, convert to 0s/1s
+  %ndx = bitv2dec(rbits)+1; 
+  twos = pow2(0:ndims-1);
+  ndx = ((subv-1) * twos(:)) + 1;
+  %ndx = sum((subv-1) .* twos(ones(ncases,1), :), 2) + 1; % equivalent to matrix * vector
+  %ndx = sum((subv-1) .* repmat(twos, ncases, 1), 2) + 1; % much slower than ones
+  %ndx = ndx(:)';
+else
+  %siz = siz(:)';
+  cp = [1 cumprod(siz(1:end-1))]';
+  %ndx = ones(ncases, 1);
+  %for i = 1:ndims
+  %  ndx = ndx + (subv(:,i)-1)*cp(i);
+  %end
+  ndx = (subv-1)*cp + 1;
+end
+
+%%%%%%%%%%%
+
+function d = bitv2dec(bits)
+% BITV2DEC Convert a bit vector to a decimal integer
+% d = butv2dec(bits)
+%
+% This is just like the built-in bin2dec, except the argument is a vector, not a string.
+% If bits is an array, each row will be converted.
+
+[m n] = size(bits);
+twos = pow2(n-1:-1:0);
+d = sum(bits .* twos(ones(m,1),:),2);
+