It is a Matlab function that determines the zero of a regular real function.
zero=newton_raphson(function,error)
The function has two input variable: 'function' is a string that represents the function of which find the relative zero. It must be expressed with the real variable 'x'. 'error' is the tolerance for the algorithm's arrest.
The function returns the zero point of the real function. It plots, in a figure, the function and the tangents used for the search of the zero.
The documentation is not written in English and does not follow the Matlab standards: "Calcola lo zero per una funzione scalare di variabile scalare inserita in
ingresso utilizzando l'algoritmo di Newton-Raphson. 'Tollerenza' รจ il paramentro di arresto dell'algoritmo." If you can understand this and find out, what "d_f = inline(char(diff(funzione)));" is useful for, this submission could be useful for you. But it seems to be limited to functions on the interval [0, 10] and uses a fixed stepwidth of 0.01, but without any useful comments, this is hard to check. Therefore I estimate this function as not usable and not useful.