Avi Gozolchiani אבי גוזולצני

  1: % purpose : interface for imagesc for producing good 
  2: % heat maps
  3: % syntax : myimagesc(x,y,w,minval,maxval,bin,[mask],[flag_verbose])
  4: % x,y = vectors, representing the range of x and y axis.
  5: % w = typically, a  field which depends on both x and y.
  6: % minval, maxval = first and last values of w  which are color coded.
  7: % values of w which go beyond minval and maxval will be represented by the
  8: % same colorcoding like minval and maxval
  9: % bin - an interval of values of w which has a unique color coding
 10: % mask - binary matrix for pixels that myimagesc grays out
 11: % flag_verbose - work in verbose mode
 12: % 
 13: % dependencies : verbose_disp
 14: % 
 15: % see also: imagesc
 16: 
 17: 
 18: % Copyright 2012 Avi Gozolchiani (http://tiny.cc/avigoz)
 19: % This program is free software: you can redistribute it and/or modify
 20: % it under the terms of the GNU General Public License as published by
 21: % the Free Software Foundation, either version 3 of the License, or
 22: % (at your option) any later version.
 23: %
 24: % This program is distributed in the hope that it will be useful,
 25: % but WITHOUT ANY WARRANTY; without even the implied warranty of
 26: % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 27: % GNU General Public License for more details.
 28: %
 29: % You should have received a copy of the GNU General Public License
 30: % along with this program.  If not, see <http://www.gnu.org/licenses/>.
 31: 
 32: % $Log$
 33: function h=myimagesc(x,y,w,minval,maxval,bin,varargin)
 34: %test case
 35: % bin=1e4;minval=-8e4;maxval=8e4;
 36: % x=0.1:0.1:100;
 37: % y=0:200;
 38: % [xx,yy]=ndgrid(x,y);
 39: % w=sin(xx).*xx.^2.*exp(0.01*yy);
 40: % w(:,195:198)=-70000;
 41: % w(15:18,:)=70000;
 42: % myimagesc(x,y,w,minval,maxval,bin)
 43: accur=1e-6; % to avoid roundoff problems when interpolating the colormap
 44: %% check the inputs
 45: if(~isempty(nargchk(6,8,nargin)))
 46:   error('esyntax : myimagesc(x,y,w,minval,maxval,bin,[mask],[flag_verbose])');
 47: end
 48: nxx=length(x);
 49: nyy=length(y);
 50: [nxw,nyw]=size(w);
 51: if(nxx~=nxw || nyy~=nyw)
 52:     error('dimension mismatch');
 53: end % if(nxx~=nxw || nyy~=nyw)
 54: if(minval>=maxval)
 55:     error('minval>=maxval');
 56: end % if(minval>=maxval)
 57: if(bin>=(maxval-minval)/2.0)
 58:     error('color range spans less than two colors');
 59: end % if(bin>=(maxval-minval)/2.0)
 60: mask=zeros(nxx,nyy);
 61: flag_mask=false;
 62: if(nargin>6)
 63:     flag_mask=true;
 64:     mask=varargin{1};
 65:     if(~all([nxx,nyy]==size(mask)))
 66:         error('mask dimension does not match the other matrices');
 67:     end % if(~all([nxx,nyy]==size(mask)))
 68: end % if(nargin>6)
 69: %% parameters
 70: flag_verbos=false;
 71: if(nargin==8)
 72:     flag_verbos=varargin{2};
 73: end % if(nargin==8)
 74: accur=1e-5;
 75: %% prepare colormap
 76: verbose_disp(flag_verbos,'myimagesc : prepare colormap');
 77: colormap('default');
 78: cmap=colormap;
 79: n_origbins=size(cmap,1);
 80: W_bins=minval:bin:maxval;
 81: W_bins_ext=(minval-bin/2):bin:(maxval+(1+accur)*bin/2);
 82: cscal=(minval:(maxval-minval)/(n_origbins-1):maxval)';
 83: newcmap=interp1(cscal,cmap,W_bins);
 84: newcmap=fix((newcmap-0.5)/accur-sign(newcmap))*accur+0.5; %take care that we don't get out of the [0,1] range
 85: colormap(newcmap);
 86: %% plot the heat map
 87: verbose_disp(flag_verbos,'myimagesc : plot the heat map');
 88: h=imagesc(x,y,w',W_bins_ext([1 length(W_bins_ext)]));hh=colorbar;grid on;
 89: set(hh,'ytick',W_bins);
 90: %% plot the mask, if necessary
 91: verbose_disp(flag_verbos,'myimagesc : plot the mask, if necessary');
 92: if(flag_mask)
 93:     % see
 94:     % http://blogs.mathworks.com/steve/2009/02/18/image-overlay-using-transparency/
 95:     % for details
 96:     gray_lev=0.5*ones(size(w')); % gray level for masking
 97:     hold on;
 98:     gray=cat(3,gray_lev,gray_lev,gray_lev);
 99:     hh=imagesc(x,y,gray);
100:     hold off;
101:     set(hh,'alphadata',~mask');
102: end % if(flag_mask)
103: %% invert the y-axis
104: verbose_disp(flag_verbos,'myimagesc : invert the y-axis');
105: set(gca,'YDir','normal');