MATLAB: I want to use ezpolar with line colour, style, width control. Is this possible

ezpolarMATLAB

I want to use ezpolar with line colour, style, width control. Is this possible?

Best Answer

The ezpolar command has a return argument. This is a handle to the graphics object it creates. You can set properties on that:

h = ezpolar('sin(2*t).*cos(3*t)',[0 pi])
h.LineStyle = ':'
h.Color = 'green'
h.LineWidth = 8

Note that the "dot notation" syntax was introduced in 2014b. The following version would work in earlier releases too.

h = ezpolar('sin(2*t).*cos(3*t)',[0 pi])
set(h,'LineStyle', ':', 'Color', 'green', 'LineWidth', 8)

You can learn more about working with handles to graphics objects starting at this doc page .

Related Solutions

MATLAB: Plot tools：add data color

If you want to make the line black at the time of plotting, add the argument 'k' to the plot command.

Example:

figure;
x = 0:0.1:10;
y = sin( x );
plot( x , y , 'k');

If you have a line that is blue and you want to make it black, you can use findobj to get the handle of the blue line and then set its color property value to black manually.

Example:

% plot something
figure;
x = 0:0.1:10;
y = sin( x );
plot( x , y  , 'Blue' );
% the color values for blue and black
blue  = [ 0 0 1 ];
black = [ 0 0 0 ];
% get the handle for the blue line
hline = findobj( gca , 'color' , blue );
% Set the line's color property value to black 
set( hline(1) , 'color' , black )

MATLAB: Theta marked in radians for ezpolar

polarplot uses polaraxes whereas expolar creates a pseudo-polar-plot on regular Cartesian axes. The ThetaAxisUnits property is not available with Cartesian axes. Instead, the theta ticks are added as text objects.

I recommend using polaraxes unless you have a very good reason not to.

To convert the theta ticks in the expolar plot to radians, you'll have to identify which text objects are the theta ticks and then convert them to radians.

This demo uses fractions to label the theta ticks.

ezpolar(@(t) 1+3/2*sin(2*t), [0, 2*pi])
ax=gca;
% Get all text objects
h = findall(ax, 'type', 'text');
% Loop through each text object.  If it appears to be a 
% theta tick label, convert it to radians. 
existingTicks = 0:30:360;  % List existing theta ticks
existingTickStr = strsplit(num2str(existingTicks)); 
for i = 1:numel(h)
    if ismember(h(i).String, existingTickStr)
        [num,denom] = rat(str2double(h(i).String)/180);
        if num==0 || denom==1 
            h(i).String = sprintf('%d\\pi', num/denom);
        else
            h(i).String = sprintf('^{%d}/_{%d} \\pi', num, denom);
        end
    end
end

For more simpler decimal labels, replace the inside of the loop with,

if ismember(h(i).String, existingTickStr)
    h(i).String = sprintf('%.2f',str2double(h(i).String)*pi/180);
end

Best Answer

Related Solutions

MATLAB: Plot tools：add data color

MATLAB: Theta marked in radians for ezpolar

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