So one way around this problem is to divide the vector by the minimum value of the vector so that on a log scale the minimum value is zero (20*log10 (1)=0). It is basically useful to generate plot either for very large values or very small positive values. To create a plot using a log (base 10) scale for both the x-axis and and the y-axis you can use the function loglog. Chi Zhang 2007-10-29 23:49:37 UTC. The code figures out the maximum absolute rho, draws a square twice that size, then asks the plot subsystem how big the automatically calculated bounds were, and uses those automatic bounds to construct the circles. thanks very much for your time! I have a matrix of data. I see two methods to solve this issue: let MATLAB directly plot the data points as polar. Choose a web site to get translated content where available and see local events and offers. is it possible at all to plot polar plots with a logarithmic scale using polar.m (the standard polar function), or otherwise? The MATLAB M-file used to create this plot is experr.m. Log scale on both axes. Unable to complete the action because of changes made to the page. I am trying to plot radiation patterns for antennas on a polar plot. Polar plots start at r=0 at the center, so a log polar plot would have to start at log(0) = -infinity at the center. So one way around this problem is to divide the vector by the minimum value of the vector so that on a log scale the minimum value is zero (20*log10(1)=0). MATLAB: Log scale for radius axis in a polar plot. The circles and spokes are now drawn as solid lines instead of dots. polar polar scatter r-axis. Learn more about polar, polar scatter, r-axis Hi, i need to simulate a plannar array and i need to use progressive phase, but when i introduce that into the formula, doesnt happen anything. It plots data sets of both ‘x’ and ‘y’ axes in the logarithmic scale. Remember, when you use log, there is an infinite distance in log scale between y = 1 and y = 0, since it has to pass through y = exp(-1), y = exp(-2), y = exp(-3), and so on, each of which needs to be allocated the same screen distance as between y = exp(0) and y = exp(1) . logarithmic scale for polar plots?. MATLAB has various functions which allow 2D Plotting. To create a plot with a linear scale on the x-axis and a log (base 10) scale on the x-axis you can use the function semilogx. To get to negative y, you would have to go "further than infinity" down the bottom of the plot. Similarly, the POLAR and HOLD functions also behave in the same manner. However, this is extremely slow. https://la.mathworks.com/matlabcentral/answers/442489-log-scale-for-radius-axis-in-a-polar-plot#answer_358925, https://la.mathworks.com/matlabcentral/answers/442489-log-scale-for-radius-axis-in-a-polar-plot#comment_666399, https://la.mathworks.com/matlabcentral/answers/442489-log-scale-for-radius-axis-in-a-polar-plot#comment_666408, https://la.mathworks.com/matlabcentral/answers/442489-log-scale-for-radius-axis-in-a-polar-plot#comment_667164, https://la.mathworks.com/matlabcentral/answers/442489-log-scale-for-radius-axis-in-a-polar-plot#comment_667168, https://la.mathworks.com/matlabcentral/answers/442489-log-scale-for-radius-axis-in-a-polar-plot#answer_556148. For a full list, see PolarAxes Properties. Internally polar() uses cartesian coordinates, not polar coordinates, so there is no possibility of doing something like set(gca, 'RScale', 'log'). polar plot logarithmic. 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