Mercurial > hg > octave-lojdl
changeset 3486:9493fe321888
[project @ 2000-01-28 05:05:41 by jwe]
author | jwe |
---|---|
date | Fri, 28 Jan 2000 05:05:42 +0000 |
parents | e5d5848370c9 |
children | 8a72d9e400da |
files | scripts/ChangeLog scripts/general/reshape.m scripts/image/ind2gray.m scripts/image/ind2rgb.m scripts/image/rgb2ind.m scripts/signal/sinc.m |
diffstat | 6 files changed, 34 insertions(+), 86 deletions(-) [+] |
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--- a/scripts/ChangeLog +++ b/scripts/ChangeLog @@ -1,3 +1,13 @@ +2000-01-27 John W. Eaton <jwe@bevo.che.wisc.edu> + + * signal/sinc.m: Avoid reshaping. + + * image/rgb2ind.m: No longer needs to reset do_fortran_indexing. + * image/ind2rgb.m: Ditto. + * image/ind2gray.m: Ditto. + * general/reshape.m: Ditto. Also no longer needs to reset + implicit_str_to_num_ok. + 2000-01-26 John W. Eaton <jwe@bevo.che.wisc.edu> * miscellaneous/popen2.m: Deal with the fact that pipe now returns
--- a/scripts/general/reshape.m +++ b/scripts/general/reshape.m @@ -64,20 +64,11 @@ if (nargin == 3) [nr, nc] = size (a); if (nr * nc == m * n) - dfi = do_fortran_indexing; - istno = implicit_str_to_num_ok; - unwind_protect - do_fortran_indexing = 1; - implicit_str_to_num_ok = 1; - retval = zeros (m, n); - retval (:) = a; - if (isstr (a)) - retval = setstr (retval); - endif - unwind_protect_cleanup - do_fortran_indexing = dfi; - implicit_str_to_num_ok = istno; - end_unwind_protect + retval = zeros (m, n); + if (isstr (a)) + retval = setstr (retval); + endif + retval(:) = a; else error ("reshape: sizes must match"); endif
--- a/scripts/image/ind2gray.m +++ b/scripts/image/ind2gray.m @@ -37,29 +37,14 @@ map = colormap (); endif - ## Convert colormap to intensity values. - - yiq = rgb2ntsc (map); - y = yiq(:,1); - - ## We need Fortran indexing capability, but be sure to save the user's - ## preference. - - pref = do_fortran_indexing; - - unwind_protect + [rows, cols] = size (X); - do_fortran_indexing = 1; - - ## Replace indices in the input matrix with indexed values in the output - ## matrix. + ## Convert colormap to intensity values (the first column of the + ## result of the call to rgb2ntsc) and then replace indices in + ## the input matrix with indexed values in the output matrix (indexed + ## values are the result of indexing the the intensity values by the + ## elements of X(:)). - [rows, cols] = size (X); - Y = y(X(:)); - Y = reshape (Y, rows, cols); - - unwind_protect_cleanup - do_fortran_indexing = pref; - end_unwind_protect + Y = reshape (((rgb2ntsc (map))(:,1))(X(:)), rows, cols); endfunction
--- a/scripts/image/ind2rgb.m +++ b/scripts/image/ind2rgb.m @@ -40,22 +40,8 @@ ## XXX FIXME XXX -- we should check size of X and map. - pref = do_fortran_indexing; - - unwind_protect - - do_fortran_indexing = 1; - - R = map (X(:), 1); - G = map (X(:), 2); - B = map (X(:), 3); - - R = reshape (R, hi, wi); - G = reshape (G, hi, wi); - B = reshape (B, hi, wi); - - unwind_protect_cleanup - do_fortran_indexing = pref; - end_unwind_protect + R = reshape (map (X(:), 1), hi, wi); + G = reshape (map (X(:), 2), hi, wi); + B = reshape (map (X(:), 3), hi, wi); endfunction
--- a/scripts/image/rgb2ind.m +++ b/scripts/image/rgb2ind.m @@ -45,20 +45,10 @@ map = zeros (hi*wi, 3); - pref = do_fortran_indexing; - - unwind_protect - - do_fortran_indexing = 1; + map(:,1) = R(:); + map(:,2) = G(:); + map(:,3) = B(:); - map(:,1) = R(:); - map(:,2) = G(:); - map(:,3) = B(:); - - X(:) = 1:(hi*wi); - - unwind_protect_cleanup - do_fortran_indexing = pref; - end_unwind_protect + X(:) = 1:(hi*wi); endfunction
--- a/scripts/signal/sinc.m +++ b/scripts/signal/sinc.m @@ -34,27 +34,13 @@ function result = sinc (x) - ## We either need to set the do_fortran_indexing variable to "true" - ## or use reshape to convert the input matrix to a vector, so that - ## we can use find to determine the elements of x that equal zero. - ## I prefer reshaping. + result = ones (size (x)); - [nr, nc] = size(x); - - nels = nr*nc; + i = (x != 0); - x = reshape(x,nels,1); - - ## Set result to all ones initially. - result = ones(nels,1); - - ## Find non-zero elements in the input matrix. - i = find(x); - - if (!isempty(i)) - result(i) = sin(pi*x(i))./(pi*x(i)); + if (any (i)) + t = pi * x(i); + result(i) = sin (t) ./ t; endif - result = reshape(result,nr,nc); - endfunction