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Zur Aufgabenblatt 5 gehöriger Quellcode. Sie können sich den Quellcode durch Anklicken des Dateinamens oben am Code-Listing herunterladen.

Zur Beachtung: Zur Bearbeitung der Aufgabe benötigen Sie weitere Dateien mit Daten, die Sie als ZIP-Archiv herunterladen können.

testLoadUVVisDataForRobustness.m

function testLoadUVVisDataForRobustness(varargin)
% TESTLOADUVVISDATAFORROBUSTNESS Check user function reading UV/Vis data
% files for robustness.
%
% Usage
%   testForRobustness
%   testForRobustness(nameOfFunctionUnderTest)
 
% (c) 2014, Till Biskup <till.biskup@physchem.uni-freiburg.de>
% 2014-01-26
 
nameOfFunctionUnderTest = 'loadUVVisData';
 
% Define function under test
functionUnderTest = str2func(nameOfFunctionUnderTest);
 
% Define structure for tests
tests = struct(...
    'title','',...
    'filename','' ...
    );
% Empty structure
tests(1) = [];
 
% Define tests, aka fill test structure with content
tests(end+1) = struct(...
    'title','Existing and properly formatted UV/Vis data file',...
    'filename','uvvis.txt' ...
    );
tests(end+1) = struct(...
    'title','Existing proper file, but no file extension given',...
    'filename','uvvis' ...
    );
tests(end+1) = struct(...
    'title','Existing file with bare ASCII data',...
    'filename','background.txt' ...
    );
tests(end+1) = struct(...
    'title','Existing file in different ASCII format',...
    'filename',[mfilename '.m'] ...
    );
tests(end+1) = struct(...
    'title','Existing file in some binary format',...
    'filename','binary.dat' ...
    );
tests(end+1) = struct(...
    'title','Non-existing file (random filename)',...
    'filename',generateRandomFilename ...
    );
 
results = logical(length(tests));
warnings = logical(length(tests));
 
% Iterate over all tests
for test = 1:length(tests)
    [results(test),warnings(test)] = testFilenameWithNumberAndTitle(...
        tests(test).filename,...
        test,...
        tests(test).title ...
        );
end
 
displayTestStatistics(tests,results,warnings);
 
    function [success,warnings] = ...
            testFilenameWithNumberAndTitle(filename,testNumber,testTitle)
        % TESTFILENAMEWITHNUMBERANDTITLE Test function with given filename.
        %
        % Usage
        %   [success,warnings] = testFilename(filename,testNumber,testTitle)
 
        success = false;
        warnings = false;
 
        displayTestNumberAndTitle(testNumber,testTitle);
 
        % Test function call
        try
            data = functionUnderTest(filename);
        catch exception
            fprintf('  %s\n  %s\n  %s\n',...
                sprintf('%s "%s", line %i.',...
                    'ATTENTION: An exception occurred in',...
                    exception.stack(1).name,...
                    exception.stack(1).line...
                    ),...
                'Exception message:',...
                exception.message);
            disp('FAILED.')
            return;
        end
 
        % Check result
        if isempty(data)
            disp(['Problem reading file "' filename '": no data.']);
            warnings = true;
        elseif ~isnumeric(data)
            disp(['Problem reading file "' filename '": no numeric data.']);
            warnings = true;
        end
        disp('PASSED.');
        success = true;
 
    end
 
end
 
function filename = generateRandomFilename
% GENERATERANDOMFILENAME Filename with randomly chosen length and (allowed)
% characters
 
% Set limits for filename length
filenameMinLength = 3;
filenameMaxLength = 20;
 
% Only alphanumeric characters and "-" and "_"
allowedCharacters = char([65:90,97:122,48:57,45,95]);
 
% Generate random filename using randi for integer pseudorandom numbers
filename = allowedCharacters(...
    randi(length(allowedCharacters),...
    1,randi([filenameMinLength filenameMaxLength],1)));
 
end
 
function displayTestNumberAndTitle(testNumber,testTitle)
% DISPLAYTESTNUMBERANDTITLE Display message on Matlab command line
% with number and title of current test.
%
% Usage
%   displayTestNumberAndTitle(testNumber,testTitle)
 
fprintf('\n%s\n',char(ones(1,60)*45));
fprintf('Test %i: %s\n',testNumber,testTitle);
 
end
 
function displayTestStatistics(tests,results,warnings)
% DISPLAYTESTSTATISTICS Display summary and statistics of tests run
%
% Usage
%   displayTestStatistics(tests,results,warnings)
 
failedTests = find(~results);
 
fprintf('\n%s\n',char(ones(1,60)*61));
fprintf('%s\n\n','Summary and statistics of tests run:');
fprintf('  Passed tests:  %i\n',numel(find(results)));
fprintf('      warnings:  %i\n',numel(find(warnings)));
fprintf('  Failed tests:  %i\n',numel(failedTests));
% If some tests failed, display number and title
if ~all(results)
    fprintf('\n  %s\n','FAILED tests (no and title):');
    for failedTest = 1:length(failedTests)
        fprintf('    %i %s\n',...
            failedTests(failedTest),...
            tests(failedTests(failedTest)).title);
    end
end
fprintf('\n%s\n\n',char(ones(1,60)*61));
 
end

Nachfolgend drei Beispiele für zwei unterschiedliche Implementationen der gleichen Aufgabe, jeweils die erste langsamer als die zweite.

Aufgabe des jeweiligen Code-Schnipsels ist die Eliminierung leerer Felder aus dem cell array.

for idx = length(cellArray):-1:1
    if isempty(cellArray{idx})
        cellArray(idx) = [];
    end
end

cellArray = cellArray(~cellfun('isempty',cellArray)); %#ok<NASGU>

for k=1:length(variable)
    % y changes size in every loop iteration
    y(k) = sin(variable(k));
end

y = zeros(length(variable),1);
for k=1:length(variable)
    % y preallocated, doesn?t change size
    y(k) = sin(variable(k));
end

x = -2:0.1:2;
y = -1.5:0.1:1.5;
[X,Y] = meshgrid(x,y);
F = X.*exp(-X.^2-Y.^2);

F = zeros(length(x),length(y));
for xi = 1:length(x)
    for yi = 1:length(y)
        F(xi,yi) = x(xi)*exp(-x(xi)^2-y(yi)^2);
    end
end