How can I plot a 2D array using polar coordinates?

Hi,

I have a 2D array, with each row representing polar angle 'theta' and each column representing 'value' at paticular radius.

When I use 'imagesc', I got this (x-axis is the radius axis, y-axis is the theta axis)

How can I plot this array in polar coordinates?

[Image Analyst]

How many rows and columns, and what is the formula relating row number to angle, and column number to radius?

[Jiong Yang]

Attached is the data. It has 157 rows and 112 columns.

I got this array by calculation. Each row equals 0.01 theta, and the total polar angle is pi/2. Each column equals 0.01 in radius.

Thank you very much.

Answer 1

[darova]

Convert your data to cartesian system of coordinates

A = xlsread('data.xlsx');
%%
t = linspace(0,pi/2,size(A,1)); % create angle
r = (1:size(A,2))*0.01;         % create radius
[T,R] = ndgrid(t,r);            % 2d matrices
[X,Y] = pol2cart(T,R);          % polar to cartesian
surf(X,Y,A,'edgecolor','none')
view(2)

[Jiong Yang]

Thank you, Darova. I tried something else and got it done. Thank you anyway!

[Ava]

Hi @Jiong Yang, may I ask how you solved this? I am working on an plotting ozone levels over Antarctica with a 2D array and would like to "imagesc" the data but with the rows and columns representing angle and radius.