test: add test for trimtorange, fix special cases

+af_tools/+utils/trimtorange.m

@@ -10,16 +10,23 @@ function [alphaTrim, clTrim, cdTrim] = trimtorange(range, alpha, cl, cd)
 narginchk(2,4);
 for i = 1:size(alpha,2)
     if nargin >= 3
-        clTrim(:,i) = cl(alpha(:,i) >= range(1) & alpha(:,i) <= range(2), i);
+        clTrim(:,i) = cl(alpha(:,i) >= range(1) & alpha(:,i) <= range(end), i);
         if nargin == 4
-            cdTrim(:,i) = cd(alpha(:,i) >= range(1) & alpha(:,i) <= range(2), i);
+            cdTrim(:,i) = cd(alpha(:,i) >= range(1) & alpha(:,i) <= range(end), i);
         else
             nargoutchk(1,2);
         end
     else
         nargoutchk(1,1);
     end
-    alphaTrim(:,i) = alpha(alpha(:,i) >= range(1) & alpha(:,i) <= range(2), i);
+    alphaTrim(:,i) = alpha(alpha(:,i) >= range(1) & alpha(:,i) <= range(end), i);
+end
+
+% If impossible to trim, just return the input
+if isempty(alphaTrim)
+    alphaTrim = alpha;
+    clTrim = cl;
+    cdTrim = cd;
 end
 
 end
\ No newline at end of file

README.md

@@ -25,10 +25,9 @@ Each function contains a complete description in its preamble. Type `help
 
 1. Either clone this repository or download a `.zip` version of the source code.
 2. Place the `+af_tools/` folder somewhere on your Matlab Path such as:
-
-- in you current project
-- in a folder that is already in Matlab's path (e.g. `/Documents/Matlab/`).
-- somewhere else, but then [explicitly add it to Matlab's Path][matlabDoc_path].
+    - in you current project
+    - in a folder that is already in Matlab's path (e.g. `/Documents/Matlab/`).
+    - somewhere else, but then [explicitly add it to Matlab's Path][matlabDoc_path].
 
 #### Remark
 
@@ -188,8 +187,9 @@ import af_tools.nacaairfoil
 
 ### plotpolars
 
-Plots the following polars: $`C_l-\alpha`$, $`C_d-\alpha`$, $`C_m-\alpha`$
-$`C_l/C_d-\alpha`$, $`C_l-C_d`$.
+Plots the following polars: $`C_l-\alpha`$  ,  
+`C_d-\alpha`$   ,   $`C_m-\alpha`$  ,  
+$`C_l/C_d-\alpha`$  ,   $`C_l-C_d`$.
 
 ```matlab
 import af_tools.plotpolars

tests/test_trimtorange.m

+% TEST_TRIMTORANGE Unitary tests for the trimtorange sub-function
+% Note:
+%   The function needs to be imported at each test, because apparently Matlab
+%   does not pass it from setupOnce() or setup().
+%   For some reasons, the whole package needs to be imported, not just the
+%   function under testing.
+
+% -----
+% Copyright 2022 Thomas Lambert <t.lambert@uliege.be>
+% ULiege - Aeroelasticity and Experimental Aerodynamics
+% Apache 2.0 License
+% https://gitlab.uliege.be/am-dept/matlab_airfoil_toolbox
+% ------------------------------------------------------------------------------
+
+
+%% Main test function
+
+function tests = test_trimtorange
+
+tests = functiontests(localfunctions);
+
+end
+
+
+%% Setup and teardown
+
+function setupOnce(testCase)  % do not change function name
+
+addpath('../.'); % Add repository to Matlab Path
+addpath('./test_utils'); % Add utils to Matlab Path
+
+% Set random number generator settings.
+testCase.TestData.currentRNG = rng;
+
+end
+
+function teardownOnce(testCase)  % do not change function name
+
+rmpath('../.'); % Remove repository from Matlab Path
+rmpath('./test_utils'); % Remove utils from Matlab Path
+
+% Restore the random number generator settings.
+s = testCase.TestData.currentRNG;
+rng(s)
+
+end
+
+function teardown(~)  % do not change function name
+
+close all; % Close all figures that would have been openend
+
+end
+
+
+%% Arguments and error tests
+
+function test_nargout(testCase)
+% Ensure that the function throws an error too many output
+
+import af_tools.utils.*
+
+range = [-5;5];
+dummy = -10:10;
+
+[~, ~] = verifyError(testCase, @() trimtorange(range, dummy), 'MATLAB:nargoutchk:tooManyOutputs');
+[~, ~, ~] = verifyError(testCase, @() trimtorange(range, dummy, dummy), 'MATLAB:nargoutchk:tooManyOutputs');
+
+end
+
+
+%% Test for correct output
+
+function test_rangeInAOA(testCase)
+% Ensure proper output if range is fully contained in alpha
+
+import af_tools.utils.*
+
+range = [-1,1]';
+alpha = (-10:10)';
+cl = alpha + 10;
+cd = alpha - 10;
+
+expAlphaTrim = (-1:1)';
+[alphaTrim, clTrim, cdTrim] = trimtorange(range, alpha, cl, cd);
+
+verifyEqual(testCase, alphaTrim, expAlphaTrim);
+verifyEqual(testCase, clTrim, expAlphaTrim+10);
+verifyEqual(testCase, cdTrim, expAlphaTrim-10);
+
+end
+
+
+function test_rangeOutAOA(testCase)
+% If range is all out of AOA, just return the input
+
+import af_tools.utils.*
+
+range = [-20,-15]';
+alpha = (-10:10)';
+cl = alpha + 10;
+cd = alpha - 10;
+
+[alphaTrim, clTrim, cdTrim] = trimtorange(range, alpha, cl, cd);
+
+verifyEqual(testCase, alphaTrim, alpha);
+verifyEqual(testCase, clTrim, cl);
+verifyEqual(testCase, cdTrim, cd);
+
+
+end
+
+
+function test_rangePartOutAOA(testCase)
+% Ensure proper output if range is partially out of alpha
+
+import af_tools.utils.*
+
+range = (-20:0)';
+alpha = (-10:10)';
+cl = alpha + 10;
+cd = alpha - 10;
+
+expAlphaTrim = (-10:0)';
+[alphaTrim, clTrim, cdTrim] = trimtorange(range, alpha, cl, cd);
+
+verifyEqual(testCase, alphaTrim, expAlphaTrim);
+verifyEqual(testCase, clTrim, expAlphaTrim+10);
+verifyEqual(testCase, cdTrim, expAlphaTrim-10);
+
+end
+
+
+function test_rangeEqualAOA(testCase)
+% Ensure proper output if range is equal to alpha
+
+import af_tools.utils.*
+
+alpha = (-10:10)';
+range = (-10:10)';
+cl = (20:40)';
+cd = (-20:0)';
+
+[alphaTrim, clTrim, cdTrim] = trimtorange(range, alpha, cl, cd);
+
+verifyEqual(testCase, alphaTrim, alpha);
+verifyEqual(testCase, clTrim, cl);
+verifyEqual(testCase, cdTrim, cd);
+
+end
+
+
+function test_scalarRange(testCase)
+% Ensure proper output if range is a scalar
+
+import af_tools.utils.*
+
+range = (0)';
+alpha = (-10:10)';
+cl = alpha + 10;
+cd = alpha - 10;
+
+expAlphaTrim = 0;
+[alphaTrim, clTrim, cdTrim] = trimtorange(range, alpha, cl, cd);
+
+verifyEqual(testCase, alphaTrim, expAlphaTrim);
+verifyEqual(testCase, clTrim, expAlphaTrim+10);
+verifyEqual(testCase, cdTrim, expAlphaTrim-10);
+
+end