# Revision history [back]

### Correct input for list_plot3d(..., interpolation='spline')

I'm trying to construct smooth surfaces from lists of points in 3-space using list_plot3d and the spline option, but without success. For example, the input

list_plot3d ([(-1, 2, 3), (2, -1, 3), (3, -1, 2), (-1 ,3 ,2), (2, 3, -1), (3, 2, -1)], interpolation_type='spline')

returns the error

TypeError: m >= (kx+1)(ky+1) must hold

The following returns the expected piecewise linear surface suggesting that there is a special restriction on the input when using the spline option.

list_plot3d ([(-1, 2, 3), (2, -1, 3), (3, -1, 2), (-1 ,3 ,2), (2, 3, -1), (3, 2, -1)])

Question: What is the correct input to obtain a best fit polynomial surface going through the six points in $\mathbb{R}^3$?

### Correct input for list_plot3d(..., interpolation='spline')

I'm trying to construct smooth surfaces from lists of points in 3-space using list_plot3d and the spline option, but without success. For example, the input

list_plot3d ([(-1, 2, 3), (2, -1, 3), (3, -1, 2), (-1 ,3 ,2), (2, 3, -1), (3, 2, -1)], interpolation_type='spline')

returns the error

TypeError: m >= (kx+1)(ky+1) must hold

The following returns the expected piecewise linear surface suggesting that there is a special restriction on the input when using the spline option.

list_plot3d ([(-1, 2, 3), (2, -1, 3), (3, -1, 2), (-1 ,3 ,2), (2, 3, -1), (3, 2, -1)])

Question: What is the correct input to obtain a best fit polynomial surface going through the six points in $\mathbb{R}^3$?

Edit: As pointed out by @slelievre, since these six points lie in a common plane, the corresponding surface should be the plane containing the points. So why does Sage throw an error instead of this plane?

### Correct input for list_plot3d(..., interpolation='spline')

I'm trying to construct smooth surfaces from lists of points in 3-space using list_plot3d and the spline option, but without success. For example, the input

list_plot3d ([(-1, 2, 3), (2, -1, 3), (3, -1, 2), (-1 ,3 ,2), (2, 3, -1), (3, 2, -1)], interpolation_type='spline')

returns the error

TypeError: m >= (kx+1)(ky+1) must hold

The following returns the expected piecewise linear surface suggesting that there is a special restriction on the input when using the spline option.

list_plot3d ([(-1, 2, 3), (2, -1, 3), (3, -1, 2), (-1 ,3 ,2), (2, 3, -1), (3, 2, -1)])

Question: What is the correct input to obtain a best fit polynomial surface going through the six points in $\mathbb{R}^3$?

Edit: As pointed out by @slelievre, since these six points lie in a common plane, the corresponding surface should be the plane containing the points. So why does Sage throw an error instead of this plane?