# tubeplot3d function in sage ?

Is there a function equivalent to the function tubeplot as appended below ? If not, how to use the script below in sage ? Or could such a function be defined in sage in the future ? Thanks for any reply ! @mfunction("varargout") def tubeplot(x=None, y=None, z=None, *varargin):

```
# TUBEPLOT - plots a tube r along the space curve x,y,z.
#
# tubeplot(x,y,z) plots the basic tube with radius 1
# tubeplot(x,y,z,r) plots the basic tube with variable radius r (either a vector or a value)
# tubeplot(x,y,z,r,v) plots the basic tube with coloring dependent on the values in the vector v
# tubeplot(x,y,z,r,v,s) plots the tube with s tangential subdivisions (default is 6)
#
# [X,Y,Z]=tubeplot(x,y,z) returns [Nx3] matrices suitable for mesh or surf
#
# Note that the tube may pinch at points where the normal and binormal
# misbehaves. It is suitable for general space curves, not ones that
# contain straight sections. Normally the tube is calculated using the
# Frenet frame, making the tube minimally twisted except at inflexion points.
#
# To deal with this problem there is an alternative frame:
# tubeplot(x,y,z,r,v,s,vec) calculates the tube by setting the normal to
# the cross product of the tangent and the vector vec. If it is chosen so
# that it is always far from the tangent vector the frame will not twist unduly
#
# Example:
#
# t=0:(2*pi/100):(2*pi);
# x=cos(t*2).*(2+sin(t*3)*.3);
# y=sin(t*2).*(2+sin(t*3)*.3);
# z=cos(t*3)*.3;
# tubeplot(x,y,z,0.14*sin(t*5)+.29,t,10)
#
# Written by Anders Sandberg, asa@nada.kth.se, 2005
subdivs = 6
N = size(x, 1)
if (N == 1):
x = x.cT
y = y.cT
z = z.cT
N = size(x, 1)
end
if (nargin == 3):
r = x * 0 + 1
else:
r = varargin(1)
if (size(r, 1) == logical_and(1, size(r, 2) == 1)):
r = r * ones(N, 1)
end
end
if (nargin > 5):
subdivs = varargin(3) + 1
end
if (nargin > 6):
vec = varargin(4)
[t, n, b] = frame(x, y, z, vec)
else:
[t, n, b] = frenet(x, y, z)
end
X = zeros(N, subdivs)
Y = zeros(N, subdivs)
Z = zeros(N, subdivs)
theta = mslice[0:(2 * pi / (subdivs - 1)):(2 * pi)]
for i in mslice[1:N]:
X(i, mslice[:]).lvalue = x(i) + r(i) * (n(i, 1) * cos(theta) + b(i, 1) * sin(theta))
Y(i, mslice[:]).lvalue = y(i) + r(i) * (n(i, 2) * cos(theta) + b(i, 2) * sin(theta))
Z(i, mslice[:]).lvalue = z(i) + r(i) * (n(i, 3) * cos(theta) + b(i, 3) * sin(theta))
end
if (nargout == 0):
if (nargin > 4):
V = varargin(2)
if (size(V, 1) == 1):
V = V.cT
end
V = V * ones(1, subdivs)
surf(X, Y, Z, V)
else:
surf(X, Y, Z)
end
else:
varargout(1).lvalue = mcellarray([X ...
```