function figh = stackedplot(z,style,spacing,labels,varargin)
% STACKED PLOT produces a 3D-like plot as a stacked set of spectra.
% Syntax: figh = stackedplot(z,style,spacing,labels,varargin)
% Stacked plots are commonly seen in NMR spectroscopy. There are several (somewhat
% equivalent) methods to produce such plots in Matlab. This function provides a
% common interface to these various methods. Certainly some methods can be evoked
% more directly, i.e. mesh, but some others are not obivous choices, e.g. plot3.
% The purpose of this function is to educate through sample code and to provide the
% user additional choices. Select the method you like best.
% Arguments:
% "z" is a two dimensional array to plot.
% First dimension is the spectroscopic axis.
% Second dimension has the various spectra or plots (e.g. along time).
% "style" (optional) selects the method and style for the stacked plot.
% "1" or "s" (default) performs a traditional stacked plot
% This is not a 3D plot. The view cannot be rotated and there is no control
% over z tick labels.
% "2" or "m" performs a surface mesh plot
% This is a 3D plot and the camera view may be rotated
% "3" or "mc" performs a surface mesh plot with mesh lines along dim 1.
% This is a 3D plot and the camera view may be rotated
% "4" or "p" uses plot3
% This is a 3D plot and the camera view may be rotated
% "5" or "i" uses imagesc
% This simply plots the data as an image as looking from above.
% Vertical axis is the second dimension for the data.
% "spacing" (optional) is a positive integer specifying the spacing along dim 2.
% e.g. 4 specifies that every fourth point is plotted (default=1).
% "labels" controls appearance of tick labels on the axes.
% if it is a single element then it must be one of the following:
% {0, 'none'} - axis tick labels are removed (default).
% {1, 'x'} - only x-axis (dim 1) tick labels are kept.
% {2, 'y'} - only y-axis (dim 2) tick labels are kept.
% {3, 'xy'} - only x&y-axis tick labels are kept.
% {4, 'all'} - all axis tick labels are kept.
% if "labels" is numeric and has more than one element [2,4,or 6] then
% if a 2 element column vector, only x-axis tick labels are created.
% if a 2 element row vector, only y-axis tick labels are created.
% if a 4 element vector, then x & y tick labels are created.
% if a 6 element vector, then x,y,&z tick labels are created.
% Each axis "labels" has 2 elements [min, max].
% To reverse the order of the labels specify in reverse order as [max, min].
% "varargin" (optional) can be any number of arguments as needed that are passed along
% to the plotting commands. Thus this depends upon the plot sytle as follows:
% Style
% 1 - offset, numyticks, linespec
% 1st arg is offset, which is specified as a fraction of data range.
% This value represents the total displacement along each axis.
% If one element then value is repeated for both axes.
% If two elements then [xoffset,yoffset] (default = [0.1,0.8]).
% 2nd arg is number of y ticks, remember to specify y tick vector.
% 3rd arg is linespec, see Matlab help for "line" (default: 'b').
% 2 - Any property that is valid for "mesh", see Matlab help.
% 3 - Any property that is valid for "mesh", see Matlab help.
% 4 - Any property or linespec that is valid for "plot3", see Matlab help.
% 5 - clims value, see Matlab help on "imagesc".
% "figh" (optional) is the figure handle.
% Notes:
% Function "Splot" (style 1) can be extracted as a standalone function.
% Plots are made on the current figure, if no figure exists then one is created.
% If the axis labels are not in the correct direction try:
% set(gca,'XDir','normal') or set(gca,'XDir','reverse')
% 'XDir' may be substituted with 'YDir' or 'ZDir' for the corresponding axis.
% Copyright 2009-2012 Mirtech, Inc.
% created 05/30/2009 MIH
% modified 05/19/2012 MIH, changed how tick labels are specified
def_linespec = 'b';
def_style = 1;
def_spacing = 1;
def_labels = 0;
switch nargin
case 0
error (' Need a two dimensional array as input!')
case 1
spacing = []; style = []; labels = []; varargin = [];
case 2
style = []; labels = []; varargin = [];
case 3
labels = []; varargin = [];
case 4
varargin = [];
otherwise
% do nothing
end
if isempty(spacing), spacing = def_spacing; end
if isempty(style), style = def_style; end
if isempty(labels), labels = def_labels; end
z = z(:,1:spacing:end); % reduce data to only use displayed elements
zdim = size(z);
xvec = 1:zdim(1);
yvec = 1:zdim(2);
zlimits = [min(z(:)),max(z(:))];
% check "labels" specification
if ischar(labels)||numel(labels)==1,
% check single element control of labels
switch labels,
case {0, 'none', 'NONE'}
xflag = false;
yflag = false;
zflag = false;
case {1, 'x', 'X'}
xflag = true;
yflag = false;
zflag = false;
case {2, 'y', 'Y'}
xflag = false;
yflag = true;
zflag = false;
case {3, 'xy', 'XY'}
xflag = true;
yflag = true;
zflag = false;
case {4, 'all', 'ALL'}
xflag = true;
yflag = true;
zflag = true;
otherwise
error (' Labels argument is not recognized!')
end
else
% check multi-element "label" specification
switch numel(labels)
case 2
if size(labels,2)==1, % is true if column vector specifying x-ticks.
xflag = true;
yflag = false;
zflag = false;
xvec = calcticks(zdim(1),labels);
else
yflag = true;
xflag = false;
zflag = false;
yvec = calcticks(zdim(2),labels);
end
case {4,6}
xflag = true;
yflag = true;
xvec = calcticks(zdim(1),labels(1:2));
yvec = calcticks(zdim(2),labels(3:4));
if numel(labels)==4,
zflag = false;
else
zflag = true;
zlimits = labels(5:6);
end
otherwise
error (' Labels argument is not recognized!')
end
end
% Execute one of the plot styles
switch style
case {1,'p','P'} % do traditional stacked plot
switch numel(varargin),
case 0
f = splot(xvec,yvec,z);
case {1,2,3}
f = splot(xvec,yvec,z,varargin{:});
otherwise
error(' Input arguments not appropriate for syle 1!')
end
case {2,'m','M'} % do 3D surface mesh plot
[x,y] = ndgrid(xvec,yvec);
if isempty(varargin),
f = mesh(y,x,z);
else
f = mesh(y,x,z,varargin{:});
end
axis ij % keep x-axis orientation the same as expected
tmpflag = xflag; % swap flags as surface plots axes are different
xflag = yflag;
yflag = tmpflag;
axis([min(yvec(1),yvec(end)),max(yvec(1),yvec(end)),...
min(xvec(1),xvec(end)),max(xvec(1),xvec(end)),...
min(zlimits),max(zlimits)]);
case {3, 'mc', 'MC'} % do 3D surface plot with lines along columns
[x,y] = ndgrid(xvec,yvec);
if isempty(varargin),
f = mesh(y,x,z,'meshstyle','column');
else
f = mesh(y,x,z,'meshstyle','column',varargin{:});
end
axis ij % keep x-axis orientation the same as expected
tmpflag = xflag; % swap flags as surface plots axes are different
xflag = yflag;
yflag = tmpflag;
axis([min(yvec(1),yvec(end)),max(yvec(1),yvec(end)),...
min(xvec(1),xvec(end)),max(xvec(1),xvec(end)),...
min(zlimits),max(zlimits)]);
case {4, 'p3', 'P3'} % do 3D line plot
[x,y] = ndgrid(xvec,yvec);
if isempty(varargin),
f = plot3(y,x,z,def_linespec);
else
f = plot3(y,x,z,varargin{:});
end
grid on
axis ij
tmpflag = xflag; % swap flags as surface plots axes are different
xflag = yflag;
yflag = tmpflag;
axis([min(yvec(1),yvec(end)),max(yvec(1),yvec(end)),...
min(xvec(1),xvec(end)),max(xvec(1),xvec(end)),...
min(zlimits),max(zlimits)]);
case {5, 'i', 'I'} % do image
if isempty(varargin),
f = imagesc(xvec,yvec,z');
else
f = imagesc(xvec,yvec,z',varargin{:});
end
axis xy
otherwise
error (' Style argument is not recognized!')
end
% Apply axis label controls to any plot
if xvec(1)>xvec(end), set(gca,'XDir','reverse'); end
if yvec(1)>yvec(end), set(gca,'YDir','reverse'); end
if zlimits(1)>zlimits(end), set(gca,'ZDir','reverse'); end
if ~xflag, set(gca,'XTickLabel',[]), end
if ~yflag, set(gca,'YTickLabel',[]), end
if ~zflag, set(gca,'ZTickLabel',[]), end
if nargout==1,
figh = f;
end
function fh = splot(x,y,z,offset,numyticks,linespec)
% Function performs traditional stacked plot
% x is x-axis vector
% y is y-axis vector
% z, 2D data array with x along columns and y along rows.
% offset, 1 or 2 element vector specifying total offset along x & y directions.
% Value represents fraction of axis range that is devoted for incrementing
% along the axis.
% The default x and y increment is determined by dividing the total
% value by the number of plots.
% linespec, a string constant setting the line property, see Matlab help on "plot".
% numyticks, number of y ticks.
% Copyright 2009-2012 Mirtech, Inc.
% Modified 05/23/2012 so that x and y do not have to be monotonically increasing
def_yticks = 4; % default number of y ticks
def_linespec = 'b';
def_offset = [0.1,0.8];
switch nargin,
case 6
case 5
linespec = [];
case 4
numyticks = []; linespec = [];
case 3
offset = []; numyticks = []; linespec = [];
end
if isempty(numyticks), numyticks = def_yticks; end
if isempty(linespec), linespec = def_linespec; end
if isempty(offset), offset = def_offset; end
if numel(offset)==1,
offset(2) = offset(1);
end
xpts = size(z,1);
if numel(x)~=xpts, error(' X vector does not match 2D array!'), end
ypts = size(z,2);
if numel(y)~=ypts, error(' Y vector does not match 2D array!'), end
zrange = max(z(:));
delta_y = offset(2)*zrange/(ypts-1);
incx = x(2)-x(1); % calc increment from difference of adj. pts.
delta_x = floor(offset(1)*xpts/(ypts-1)); % calc x offset in pts.
xall = x(1) + ((1:(xpts+delta_x*(ypts-1)))-1)*incx;
yplt = zeros(size(xall));
yplt(fix(xpts/2)) = zrange*(1+offset(2));
fh = plot(xall,yplt,'w'); % setup length and height of plot with a white plot
set(gca,'YAxisLocation','right')
xlim([min(xall(1),xall(end)),max(xall(1),xall(end))]);
hold on
ylast = z(:,1)';
plot(x,ylast,linespec) % plot first column
ytickvec = zeros(1,ypts); % setup y ticks location holder
ytickvec(1) = ylast(end); % save first y tick location
for n = 2:ypts,
yplt = z(:,n)' + delta_y*(n-1); % add y offset to selected column
ytickvec(n) = yplt(end); % save y tick location
ylast(1:delta_x) = 0; % set offsetted points along x to zero
ylast = circshift(ylast,[0,-delta_x]); % move those points to end
ylast = max(yplt,ylast); % create new ylast
plot(x+delta_x*(n-1)*incx,ylast,linespec) % plot ylast
end
hold off
xtickvec = get(gca,'XTick');
if x(1)<x(end),
xtickvec(xtickvec>x(end)) = [];
else
xtickvec(xtickvec<x(end)) = [];
end
set(gca,'XTick',xtickvec) % setup x ticks for only the first plot
ytickspacing = floor(ypts/(numyticks-1));
yspacing = (y(2) - y(1));
yptvec = 1:ytickspacing:ypts;
if numel(yptvec) < numyticks,
yptvec = [yptvec,ypts];
else
yptvec(end) = ypts;
end
set(gca,'YTick',ytickvec(yptvec)) % setup y ticks
yvec = y(1) + (yptvec - 1)*yspacing;
sclfac = floor(max(log10(abs(yvec)))); % find the largest power of ten
if sclfac<0,
dec = floor(abs(sclfac));
field = dec + 2;
else
field = floor(abs(sclfac));
dec = [];
end
% setup y tick labels
set(gca,'YTickLabel',cellstr(num2str(yvec',...
['%',num2str(field),'.',num2str(dec),'f'])))
% ------------- splot end --------------
function [ticklbl,tickpts] = calcticks(npts,tickvector)
% calculates location of ticks and labels
% tickvector is a 2 element vector [min,max] or a
% 3 element vector [min,max,#ticks]
% if 2 then #ticks = npts
tmin = min(tickvector);
tmax = max(tickvector);
if numel(tickvector)==3,
nticks = tickvector(3);
else
nticks = npts+1;
end
tickspacing = npts/(nticks-1);
tickpts = 1:tickspacing:npts;
ticklbl = tmin:(tmax-tmin)*tickspacing/(npts-1):tmax;
if tmin==tickvector(2),
ticklbl = ticklbl(end:-1:1);
tickpts = tickpts(end:-1:1);
end
% ------------- calcticks end --------------
