fix(extpol): incorrect cd_ext when multiple polars

+af_tools/extendpolar.m

@@ -214,7 +214,7 @@ function [alpha_ext, c_l_ext, c_d_ext] = viterna(limit, alpha, c_l, c_d)
 
         % 1. Extend Cl/Cd to ]limit, 90]
         alpha_1 = (alpha_l + alpha_step:alpha_step:pi / 2)';
-        [cl1, cd1] = viternaeq(VitCoeffs, alpha_1, 1);
+        [c_l_1, c_d_1] = viternaeq(VitCoeffs, alpha_1, 1);
 
         % 2. Extend to ]90, 180-limit]
         alpha_2 = (pi / 2 + alpha_step:alpha_step:pi - alpha_l)';
@@ -251,12 +251,13 @@ function [alpha_ext, c_l_ext, c_d_ext] = viterna(limit, alpha, c_l, c_d)
 
         % Concatenate everything to get the full extended polars
         alpha_ext(:, i) = [alpha_6; alpha_5; alpha_4; trimmedAlpha; alpha_1; alpha_2; alpha_3];
-        c_l_ext(:, i) = [c_l_6; c_l_5; c_l_4; trimmedCl; cl1; c_l_2; c_l_3];
-        c_d_ext(:, i) = [c_d_6; c_d_5; c_d_4; trimmedCd; cd1; c_d_2; c_d_3];
+        c_l_ext(:, i) = [c_l_6; c_l_5; c_l_4; trimmedCl; c_l_1; c_l_2; c_l_3];
+        c_d_ext(:, i) = [c_d_6; c_d_5; c_d_4; trimmedCd; c_d_1; c_d_2; c_d_3];
 
         % Trim negatives cd to cdmin
         c_d_min = min(trimmedCd);
-        c_d_ext(c_d_ext <= c_d_min, i) = c_d_min;
+        c_d_ext(c_d_ext(:, i) <= c_d_min, i) = c_d_min;
+
     end
 
 end

tests/test_extendpolar.m

@@ -199,7 +199,7 @@ end
 
 %% Test if function returns expected outputs
 
-function test_correctAlphaSize(testCase)
+function test_correctAlphaSizeSinglePolar(testCase)
     % Verify if the output alpha has the correct size
     % Should not re-expand polar that already covers the full range
 
@@ -216,4 +216,29 @@ function test_correctAlphaSize(testCase)
     verifyEqual(testCase, clExt2, clExt);
     verifyEqual(testCase, cdExt2, cdExt);
 
+    verifyEqual(testCase, size(clExt2), size(alphaExt));
+    verifyEqual(testCase, size(cdExt2), size(alphaExt));
+
+end
+
+function test_correctAlphaSizeDoublePolar(testCase)
+    % Verify if the output alpha has the correct size
+    % Should not re-expand polar that already covers the full range
+
+    Polar = dummydoublepolar();
+    stepAlpha = min(diff(Polar.alpha));
+    fullRange = (-pi:stepAlpha:pi)';
+
+    [alphaExt, clExt, cdExt] = af_tools.extendpolar(Polar);
+    [alphaExt2, clExt2, cdExt2] = af_tools.extendpolar(alphaExt, clExt, cdExt);
+
+    verifyEqual(testCase, alphaExt(:, 1), fullRange, 'AbsTol', 1e-9);
+
+    verifyEqual(testCase, alphaExt2, alphaExt);
+    verifyEqual(testCase, clExt2, clExt);
+    verifyEqual(testCase, cdExt2, cdExt);
+
+    verifyEqual(testCase, size(clExt2), size(alphaExt));
+    verifyEqual(testCase, size(cdExt2), size(alphaExt));
+
 end