help: I need to solve the problem of the function "lsqcurvefit" I have an error when I started to run the program

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Sou Fat 2023-3-21

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评论： Sou Fat 2023-3-25

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Hello,

I have an error in the function "lsqcurvefit" that I have to use, I tried to solve the problem but I don't know what the error is exactly, I have to know that I respect the syntax of the function.?

Thank you for your help

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Torsten 2023-3-21

Neither the array "xdata" nor the array "ydata" appear in the definition of your function "fun". That's why you have only a single equation for the unknown vector x. I doubt this is what you want.

Sou Fat 2023-3-21

xdata appear in the function like the time (beacuse i wrote in the top of the programme the xdata=Duree) but ydata i declareted also but i can't use in the function .

my function is : T(t)=A+b.*(C1-C1) which C1 et C2 depend the time.

I need to find the values of x to fit the "fun" function to the ydata.?

so i don't know exactely the probleme ?

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回答（1 个）

Cris LaPierre 2023-3-21

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编辑：Cris LaPierre 2023-3-21

The error message mentions 'dot indexing', which means you have likely forgotten a multiplication symbol in your equation. I found this about halfway through your equation: Kth.x(2)

You probably meant to do elementwise multiplication: Kth.*x(2)

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Cris LaPierre 2023-3-22

I linked to the corresponding page in the documentation.

You could also just attach your excel file using the paperclip icon, but you also need to then share the code that loads that spreadsheet as well as the code that creates the variables used when calling lsqcurvefit.

Sou Fat 2023-3-25