Exemple : Tracés d'isolignes avec singularités

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Exemple : Tracés d'isolignes avec singularités

1. Définissez une fonction de 2 variables avec une singularité connue.

2. Tracez F à l'aide d'un tracé d'isolignes.

Cliquez pour copier cette expression

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3. Définissez la plage de l'axe Z comprise entre -25 et + 25.

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4. Faites un zoom avant sur la singularité en modifiant les marques de graduation de l'axe Y :

Cliquez pour copier cette expression

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Les surfaces rouge et bleue représentent les zones pour lesquelles les valeurs de l'axe Z se situent en dehors de la plage comprise entre -25 et +25.

5. Rétablissez les valeurs par défaut de l'axe Z en supprimant les 3 valeurs des marques de graduation définies par l'utilisateur.

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6. Affichez la moitié supérieure du tracé en définissant la marque de graduation minimale de l'axe Y à zéro.

Cliquez pour copier cette expression

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Le tracé d'isolignes ne peut pas calculer les données en raison de la présence d'une singularité à y=0.

7. Définissez la marque de graduation inférieure de l'axe Y à une valeur légèrement inférieure à zéro.

Cliquez pour copier cette expression

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Le tracé d'isolignes est maintenant capable de calculer les données.

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