colormapline - color-changing 2D or 3D line

% H = colormapline(X,Y,Z,C) Plot a line using a specified colormap
% If Z is given, a 3D plot with coordinates X, Y, Z is created.
% If Z is not given, a 2D plot of Y over X if created.
% If Y and Z are not given, a 2D plot of X over 1:length(X) is created.
% The plotted line uses all colors in a given colormap in ascending
% order. Other than with other functions in File Exchange, the color
% does NOT depend on any coordinate.
% Technically, length(colormap) lines are plotted, each with a different
% color from the colormap in ascending order.
% H is a handle to the complete colored line. It can be used to set
% parameters such as linewidth and linestyle.
% C is optional. If it is specified, it is used as a colormap. To use it
% with a 2D plot, use Z=[] and Y=[] if required;
%
% Examples:
%% 2D plot
% t=0:0.1:10*pi;
% h=colormapline(t.*sin(t),t.*cos(t),[],jet(128));
% set(h,'linewidth',3,'linestyle','--')
%
%% 3D plot
% t=-20*pi:0.1:20*pi;
% h=colormapline(t.*sin(t),t.*cos(t),sin(t),jet(128));
% set(h,'linewidth',3)
%
%% Minimal example (2D plot with one input)
% h=colormapline(1:1000);
%
%% 2D plot using MarkerFaceColor
% t=0:0.1:10*pi;
% h=colormapline3(t.*sin(t),t.*cos(t),[],jet(128));
% set(h,'Marker','o','LineStyle','none')
% Version 2.1, 2016-12-14
% Change from version 2 (2013-01-29):
% - Line property 'MarkerFaceColor' is now also set using the colormap.
% Behaviour of previous versions can be restored by running the
% following line after the call:
% set(H,'MarkerFaceColor','none')
% This change was triggered by Nathan's question from 04 April 2016.