Am I creating dynamic variable names?
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Recently I came across a popular thread in MATLAB Answers: https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval#answer_236124
After reading this thread, I am still not sure I have created "dynamic variable names", which should be avoided as suggested in that thread.
I have a code snippet as following:
data = [1, 2, 3];
centerX = data(1);
centerY = data(2);
centerZ = data(3);
% And use these variables afterwards
Should I avoid creating those (probably dynamic) variable names, i.e., centerX, centerY, centerZ to use those data and simply/directly use data(1), data(2), data(3) instead?
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Sulaymon Eshkabilov
2021년 11월 20일
What you are doing here is not dynamic variable naming. You're assigning a new variable name from your already assigned data.
This example shows the dynamic variable naming and assigning values to the dynamically named variables (U and V):
for jj=1:5
eval(['V' num2str(jj) '= jj'])
eval(['U' num2str(jj) '= ' 'V' num2str(jj) '*jj'])
end
Which is NOT recommended to employ.
That is equivalent to:
V = 1:5;
U = V.*V;
This one is the recommended one.
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Image Analyst
2021년 11월 22일
@hmhuang, no. He did not create the dynamically named variable. His variable names are hard coded. If the file was called foo.png, there is no variable created called foo. You could do that with eval() but as we've been discussing, that's not recommended so that's why he probably did not show it. However he's saying that some people think they want to do it because they don't realize the problems it can cause.
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