Anonymous function inside of function file

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Peter M Hogan 2019-2-12

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https://ww2.mathworks.cn/matlabcentral/answers/444605-anonymous-function-inside-of-function-file

评论： Peter M Hogan 2019-2-12

Attatched is the problem and my attempt so far.

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Peter M Hogan 2019-2-12

Thanks for the response, Walter. I am not getting the correct answer to this problem. Two things are happening. I am not able to define my "rho" function with the exponentiation as shown, as I get an error in return. I also am not sure how to include an anonymous function inside of a function as the problem asks me to do.

Jan 2019-2-12

Whenever you mention in the forum that an error occurs, post a copy of the complete message. It is easier to fix an error than to guess, what the error is.

Please post the code as text, not as screenshot. The latter does not allow to fix your code by copy&paste, but requires a re-typing of what you have done already.

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Answer 1

Jan 2019-2-12

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此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/444605-anonymous-function-inside-of-function-file#answer_360715

编辑：Jan 2019-2-12

在 MATLAB Online 中打开

Your anonymous function CfromF takes one input and converts its contents. In your code you call this function without an input argument as "(CfromF)", but you need CfromF(T) with an input argument. Please read and post the error message, which clarifies this problem.

Your function obtains the input T from the outside. You initialize F as empty matrix and overwrite T afterwards. Then the input is lost. Better: avoid smart tricks with anonymous functions. Simple convert the value directly:

function rho = density(TF)
TC = (TF - 32) * 5/9;
...

If you want to learn how to do this more complicated:

function rho = density(TF)
CfromF = @(F) (F - 32) * 5/9;
TC = CfromF(TF);
...

In both cases use the value TC afterwards.

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Peter M Hogan 2019-2-12

在 MATLAB Online 中打开

function rho = density(T)
CfromF = @(F) 5*(F-32)/9;
TC=CfromF(F);
rho=5.53*10^-8*(TC).^3-8.5*10^-6*(TC).^2+6.56*10^-5*(TC)+1;
end

ok sorry! i will learn the proper posting convention. the error is that F is underdefined. I am required to use the anon function within the .m file. I am unsure how to allow T to be an input that is then changed into the ouput of "CfromF" before being run through rho. To call this funtion I must be able to enter an array of T values; ie; T=linspace(32,82,100) and then call rho=density(T), returning an array of outputs.

Peter M Hogan 2019-2-12