Mercurial > octave-nkf
view doc/interpreter/splineimages.m @ 20651:e54ecb33727e
lo-array-gripes.cc: Remove FIXME's related to buffer size.
* lo-array-gripes.cc: Remove FIXME's related to buffer size. Shorten sprintf
buffers from 100 to 64 characters (still well more than 19 required).
Use 'const' decorator on constant value for clarity. Remove extra space
between variable and array bracket.
author | Rik <rik@octave.org> |
---|---|
date | Mon, 12 Oct 2015 21:13:47 -0700 |
parents | b439ccc9a162 |
children |
line wrap: on
line source
## Copyright (C) 2012-2015 Ben Abbott, Jonas Lundgren ## ## This file is part of Octave. ## ## Octave is free software; you can redistribute it and/or modify it ## under the terms of the GNU General Public License as published by ## the Free Software Foundation; either version 3 of the License, or (at ## your option) any later version. ## ## Octave is distributed in the hope that it will be useful, but ## WITHOUT ANY WARRANTY; without even the implied warranty of ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ## General Public License for more details. ## ## You should have received a copy of the GNU General Public License ## along with Octave; see the file COPYING. If not, see ## <http://www.gnu.org/licenses/>. function splineimages (d, nm, typ) set_graphics_toolkit (); set_print_size (); hide_output (); outfile = fullfile (d, [nm "." typ]); if (strcmp (typ, "png")) set (0, "defaulttextfontname", "*"); endif if (strcmp (typ, "eps")) d_typ = "-depsc2"; else d_typ = ["-d" typ]; endif if (strcmp (typ, "txt")) image_as_txt (d, nm); elseif (strcmp (nm, "splinefit1")) ## Breaks and Pieces x = 2 * pi * rand (1, 200); y = sin (x) + sin (2 * x) + 0.2 * randn (size (x)); ## Uniform breaks breaks = linspace (0, 2 * pi, 41); ## 41 breaks, 40 pieces pp1 = splinefit (x, y, breaks); ## Breaks interpolated from data pp2 = splinefit (x, y, 10); ## 11 breaks, 10 pieces ## Plot xx = linspace (0, 2 * pi, 400); y1 = ppval (pp1, xx); y2 = ppval (pp2, xx); plot (x, y, ".", xx, [y1; y2]); axis tight; ylim ([-2.5 2.5]); legend ("data", "41 breaks, 40 pieces", "11 breaks, 10 pieces"); print (outfile, d_typ); elseif (strcmp (nm, "splinefit2")) ## Spline orders ## Data (200 points) x = 2 * pi * rand (1, 200); y = sin (x) + sin (2 * x) + 0.1 * randn (size (x)); ## Splines pp1 = splinefit (x, y, 8, "order", 0); ## Piecewise constant pp2 = splinefit (x, y, 8, "order", 1); ## Piecewise linear pp3 = splinefit (x, y, 8, "order", 2); ## Piecewise quadratic pp4 = splinefit (x, y, 8, "order", 3); ## Piecewise cubic pp5 = splinefit (x, y, 8, "order", 4); ## Etc. ## Plot xx = linspace (0, 2 * pi, 400); y1 = ppval (pp1, xx); y2 = ppval (pp2, xx); y3 = ppval (pp3, xx); y4 = ppval (pp4, xx); y5 = ppval (pp5, xx); plot (x, y, ".", xx, [y1; y2; y3; y4; y5]); axis tight; ylim ([-2.5 2.5]); legend ({"data", "order 0", "order 1", "order 2", "order 3", "order 4"}); print (outfile, d_typ); elseif (strcmp (nm, "splinefit3")) ## Data (100 points) x = 2 * pi * [0, (rand (1, 98)), 1]; y = sin (x) - cos (2 * x) + 0.2 * randn (size (x)); ## No constraints pp1 = splinefit (x, y, 10, "order", 5); ## Periodic boundaries pp2 = splinefit (x, y, 10, "order", 5, "periodic", true); ## Plot xx = linspace (0, 2 * pi, 400); y1 = ppval (pp1, xx); y2 = ppval (pp2, xx); plot (x, y, ".", xx, [y1; y2]); axis tight; ylim ([-2 3]); legend ({"data", "no constraints", "periodic"}); print (outfile, d_typ); elseif (strcmp (nm, "splinefit4")) ## Data (200 points) x = 2 * pi * rand (1, 200); y = sin (2 * x) + 0.1 * randn (size (x)); ## Breaks breaks = linspace (0, 2 * pi, 10); ## Clamped endpoints, y = y" = 0 xc = [0, 0, 2*pi, 2*pi]; cc = [(eye (2)), (eye (2))]; con = struct ("xc", xc, "cc", cc); pp1 = splinefit (x, y, breaks, "constraints", con); ## Hinged periodic endpoints, y = 0 con = struct ("xc", 0); pp2 = splinefit (x, y, breaks, "constraints", con, "periodic", true); ## Plot xx = linspace (0, 2 * pi, 400); y1 = ppval (pp1, xx); y2 = ppval (pp2, xx); plot (x, y, ".", xx, [y1; y2]); axis tight; ylim ([-1.5 1.5]); legend ({"data", "clamped", "hinged periodic"}); print (outfile, d_typ); elseif (strcmp (nm, "splinefit5")) ## Truncated data x = [0, 1, 2, 4, 8, 16, 24, 40, 56, 72, 80] / 80; y = [0, 28, 39, 53, 70, 86, 90, 79, 55, 22, 2] / 1000; xy = [x; y]; ## Curve length parameter ds = sqrt (diff (x).^2 + diff (y).^2); s = [0, cumsum(ds)]; ## Constraints at s = 0: (x,y) = (0,0), (dx/ds,dy/ds) = (0,1) con = struct ("xc", [0 0], "yc", [0 0; 0 1], "cc", eye (2)); ## Fit a spline with 4 pieces pp = splinefit (s, xy, 4, "constraints", con); ## Plot ss = linspace (0, s(end), 400); xyfit = ppval (pp, ss); xyb = ppval (pp, pp.breaks); plot (x, y, ".", xyfit(1,:), xyfit(2,:), "r", xyb(1,:), xyb(2,:), "ro"); legend ({"data", "spline", "breaks"}); axis tight; ylim ([0 0.1]); print (outfile, d_typ); elseif (strcmp (nm, "splinefit6")) ## Data x = linspace (0, 2*pi, 200); y = sin (x) + sin (2 * x) + 0.05 * randn (size (x)); ## Add outliers x = [x, linspace(0,2*pi,60)]; y = [y, -ones(1,60)]; ## Fit splines with hinged conditions con = struct ("xc", [0, 2*pi]); pp1 = splinefit (x, y, 8, "constraints", con, "beta", 0.25); ## Robust fitting pp2 = splinefit (x, y, 8, "constraints", con, "beta", 0.75); ## Robust fitting pp3 = splinefit (x, y, 8, "constraints", con); ## No robust fitting ## Plot xx = linspace (0, 2*pi, 400); y1 = ppval (pp1, xx); y2 = ppval (pp2, xx); y3 = ppval (pp3, xx); plot (x, y, ".", xx, [y1; y2; y3]); legend ({"data with outliers","robust, beta = 0.25", ... "robust, beta = 0.75", "no robust fitting"}); axis tight; ylim ([-2 2]); print (outfile, d_typ); endif hide_output (); endfunction ## This function no longer sets the graphics toolkit; That is now done ## automatically by C++ code which will ordinarily choose 'qt', but might ## choose gnuplot on older systems. Only a complete lack of plotting is a ## problem. function set_graphics_toolkit () if (isempty (available_graphics_toolkits ())) error ("no graphics toolkit available for plotting"); endif endfunction function set_print_size () image_size = [5.0, 3.5]; # in inches, 16:9 format border = 0; # For postscript use 50/72 set (0, "defaultfigurepapertype", "<custom>"); set (0, "defaultfigurepaperorientation", "landscape"); set (0, "defaultfigurepapersize", image_size + 2*border); set (0, "defaultfigurepaperposition", [border, border, image_size]); endfunction ## Use this function before plotting commands and after every call to print ## since print() resets output to stdout (unfortunately, gnuplot can't pop ## output as it can the terminal type). function hide_output () hf = figure (1, "visible", "off"); endfunction ## generate something for the texinfo @image command to process function image_as_txt (d, nm) fid = fopen (fullfile (d, [nm ".txt"]), "wt"); fputs (fid, "\n"); fputs (fid, "+---------------------------------+\n"); fputs (fid, "| Image unavailable in text mode. |\n"); fputs (fid, "+---------------------------------+\n"); fclose (fid); endfunction %!demo %! for s = 1:6 %! splineimages (sprintf ("splinefit##d", s), "pdf") %! endfor