How Can I plot 3D color bar plot?

Hello.

I'm trying to plot 3D coloured bar graph, in which every bar is colored with color of Z axis value accordingly.

X, Y and Z axis data are all individual, like X:Y:Z = [22.4: 34.5: 34, 23.1: 56.7: 23,........]

but i can't find out how to programme this with bar3 function (use this on 3D). Has anyone any solution?

Answer 1

[Image Analyst]

Feel free to adapt my demo:

% Demo macro plot a bar chart and give a different color to each bar.
% Also plots the value of the bar above the bar.
clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
clear;  % Erase all existing variables.
workspace;  % Make sure the workspace panel is showing.
fontSize = 30;
format compact

% Ask user for the number of bars.
defaultValue = 7;
titleBar = 'Enter an integer value';
userPrompt = 'Enter the number of bars';
caUserInput = inputdlg(userPrompt, titleBar, 1, {num2str(defaultValue)});
if isempty(caUserInput),return,end; % Bail out if they clicked Cancel.
integerValue = round(str2double(cell2mat(caUserInput)));
% Check for a valid integer.
if isnan(integerValue)
    % They didn't enter a number.  
    % They clicked Cancel, or entered a character, symbols, or something else not allowed.
    integerValue = defaultValue;
    message = sprintf('I said it had to be an integer.\nI will use %d and continue.', integerValue);
    uiwait(warndlg(message));
end

% Define sample data in the range 20-80.
x = 1 : integerValue;
y = 20 + 80 * rand(integerValue)
numberOfBars = length(y);

button = menu('Use which colormap?', 'Custom', 'Random', 'Jet', 'Hot', 'Lines');
if button == 1
  % Make up a custom colormap specifying the color for each bar series.
  barColorMap(1,:) = [.2 .71 .3];  % Green Color for segment 1.
  barColorMap(2,:) = [.25 .55 .79];  % Blue Color for segment 2.
  barColorMap(3,:) = [.9 .1 .14];  % Red Color for segment 3.
  barColorMap(4,:) = [.9 .9 .14];  % Yellow Color for segment 4.
  % I have not defined any more than 4 colors in this demo.
  % For any number of bars beyond 4, just make up random colors.
  if numberOfBars > 4
    barColorMap(5:numberOfBars, 1:3) = rand(numberOfBars-4, 3);
  end
elseif button == 2
  % Example of using colormap with random colors
  barColorMap = rand(numberOfBars, 3); 
elseif button == 3
  % Example of using pre-defined jet colormap
  barColorMap = jet(numberOfBars); 
elseif button == 4
  % Example of using pre-defined Hot colormap
  barColorMap = hot(numberOfBars); 
else
  % Example of using pre-defined lines colormap
  barColorMap = lines(numberOfBars); 
end

% Plot each number one at a time, calling bar() for each y value.
barFontSize = 15;
for b = 1 : numberOfBars
  % Plot one single bar as a separate bar series.
  handleToThisBarSeries(b) = bar(x(b), y(b), 'BarWidth', 0.9);
  % Apply the color to this bar series.
  set(handleToThisBarSeries(b),'FaceColor', barColorMap(b,:));
  % Place text atop the bar
  barTopper = sprintf('y(%d) = %.3f', x(b), y(b));
  text(x(b)-0.2, y(b)+3, barTopper, 'FontSize', barFontSize);
  hold on;
end

% Fancy up the graph.
grid on;
caption = sprintf('Data plotted in %d barseries, each with a different color', length(y));
title(caption, 'FontSize', fontSize);
xlabel('x', 'FontSize', fontSize);
ylabel('y', 'FontSize', fontSize);
% Restore the x tick marks.
set(gca, 'XTickMode', 'Auto');
% set(gca, 'XTickLabels', xTickLabels);
% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]);
% Give a name to the title bar.
set(gcf,'name','Demo by ImageAnalyst','numbertitle','off');

[Nibedita]

Thanks for the suggestion but its not 3D graph, how it could be 3D with respect to the color cool at per Z axis data

[Image Analyst]

I said you can adapt it, which means you will have to. That means you can do things like replace bar() with bar3().