[For comparison only] Legendre-Fenchel conjugate, direct computation on {1,...,n}
Conj = pl_lft_direct_d(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).
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).
Warning: This function is provided only for comparison purposes and unit testing, use the more efficient pl_lft_llt_d for faster computation.
Wrap over for easier computation of distance transforms. The function calls pl_lft_direct(X,Y,S) with n=length(Y), X=(1:1:n)' and S=X. See pl_lft_direct for more information.
row = [1 2.5 5 8.5 13]'; conj_part = -1.*pl_lft_direct_d(row); b = isequal(conj_part, [0 -1.5 -4 -7.5 -12]'); | ![]() | ![]() |
Yves Lucet
, University of British Columbia, BC, Canada