lft_direct_d - [For comparison only] Legendre-Fenchel conjugate, direct computation on {1,...,n}

Calling Sequence

Conj = lft_direct_d(Y)

Parameters

• Y : column vector. The value of the function on the grid {1,...,n}: usually Y(i)=f(i) for some function f, with 1 <= i <= n and n=length(Y).
• Conj : column vector. Contains the value of the conjugate f* of the function f evaluated at the points j. In other words: Conj(j) = Max(j * i - Y(i) | over all indexes i).

Description

Warning: This function is provided only for comparison purposes and unit testing, use the more efficient lft_llt_d for faster computation.

Wrap over for easier computation of distance transforms. The function calls lft_direct(X,Y,S) with n=length(Y), X=(1:1:n)' and S=X. See lft_direct for more information.

Examples

        row = [1 2.5 5 8.5 13]';
        conj_part = -1.*lft_direct_d(row);
        b = isequal(conj_part, [0 -1.5 -4 -7.5 -12]');
  

See Also

lft_direct,  lft_llt_d,  

Author

Yves Lucet, University of British Columbia, BC, Canada

Used Function