Esempio: regressione non lineare 1

Funzioni > Analisi dati > Curve fitting > Esempio: regressione non lineare 1

Utilizzare la funzione genfit per trovare i parametri di fit per un fit non lineare generale.

1. Definire un insieme di dati.

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2. Costruire la funzione da inserire nella funzione genfit. Immettere la funzione adattata e quindi aggiungere le derivate relative a ogni parametro. Per le derivate, utilizzare la funzione exp anziché e.

I parametri devono essere specificati come elementi in un vettore di parametri, utilizzando l'operatore di indicizzazione.

3. Specificare i valori ipotizzati.

4. Chiamare la funzione genfit.

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5. Tracciare il grafico dell'insieme di dati e del fit non lineare generale.

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6. Utilizzare la funzione corr per controllare la correlazione tra vy e GNfit.

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Il fit è perfetto, come confermato dal risultato precedente.

Riferimenti

I dati per questo esempio sono tratti da Lanczos, C., Applied Analysis, Prentice Hall, 1956, pagine 272-280, come illustrato nell'archivio NIST Statistical Reference Dataset Archive.

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