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    %% 2-D Plots
% This example shows some of the many types of 2-D line that you
% can create with MATLAB(R) and provides a few general plotting tips.

%   Copyright 1984-2014 The MathWorks, Inc.

%% Line Plot of a Chirp
% This example shows a basic line plot of a chirp signal. It also shows how
% to enter labels for the _x_ and _y_ axes using |xlabel| and |ylabel| as
% well as one method of initializing _x_-values. Type |doc linspace| at the
% command prompt for information on another method for initializing evenly
% spaced data sets. Here y-values are computed as a function of |x| and 
% stored in the variable |y|, but you could also plot just the computed
% y-values in one command, for example, |plot(sin((0:0.05:5).^2))|.

x = 0:0.05:5;
y = sin(x.^2); 
plot(x,y);
xlabel('Time')
ylabel('Amplitude')


%% Bar Plot of a Bell Shaped Curve
% As just suggested, you don't need a variable to hold _y_-values if you
% pass a function that generates them to |plot| as its y-argument.

x = -2.9:0.2:2.9;
bar(x,exp(-x.*x)); 


%% Stairstep Plot of a Sine Wave

x = 0:0.25:10;
stairs(x,sin(x));


%% Errorbar Plot
% The errorbar function draws a line plot of _x_ and _y_ values and
% superimposes on each observation a vertical error bar, the extent of
% which depends on an additional argument. Here the error data is created 
% in line 3 using the rand function, which generates a sequence of random 
% numbers.

x = -2:0.1:2;
y = erf(x);
e = rand(size(x))/10; 
errorbar(x,y,e);


%% Polar Plot
% This example plots the polar coordinates of the angle theta (|t|, in 
% radians) versus the radius, |rho|.

t = 0:0.01:2*pi;
polar(t,abs(sin(2*t).*cos(2*t)));


%% Stem Plot
% A stem plot draws a marker for each _x_, _y_ value which is connected to a
% common baseline by a vertical line.

x = 0:0.1:4;
y = sin(x.^2).*exp(-x);
stem(x,y)


%% Scatter Plot
% This example shows the relationship between traffic counts on two streets 
% hour by hour using red stars for markers.  The previous example used the 
% default markers of empty blue circles.  For more 
% information on changing line styles, colors, and markers, type 
% |doc line|, |doc scatter|, or |doc line_props| in the command line.

load count.dat
scatter(count(:,1),count(:,2),'r*')
xlabel('Number of Cars on Street A');
ylabel('Number of Cars on Street B');