CoCalc Shared FilesBookcapa.sagews
Author: Leon Denis
Views : 37
G = Graphics()
for k in range(1,2001):
z = (cos(6*pi*k/2000)-I*cos(12*pi*k/2000))*e^(3*pi*I/4)
w = (sin(4*pi*k/2000+pi/8)+I*sin(2*pi*k/2000+pi/3))*e^(3*pi*I/4)
G+=line([(z.real(), z.imag()), (w.real(), w.imag())], thickness = 0.1)
G.show(aspect_ratio = 1)

r = 0.5
t, v = var('t, v')
alpha = vector((cos(t), sin(t), t/2))

N = diff(alpha, t, 2)/norm(diff(alpha, t, 2))
b = diff(alpha, t).cross_prodtct(diff(alpha, t, 2))
B = b/norm(b)

x = alpha + r*cos(v)*N + r*sin(v)*B;
parametric_plot3d(x, (t, 0, 4*pi), (v, 0, 2*pi))

Error in lines 5-5 Traceback (most recent call last): File "/cocalc/lib/python2.7/site-packages/smc_sagews/sage_server.py", line 1044, in execute exec compile(block+'\n', '', 'single', flags=compile_flags) in namespace, locals File "", line 1, in <module> File "sage/structure/element.pyx", line 493, in sage.structure.element.Element.__getattr__ (build/cythonized/sage/structure/element.c:4515) return self.getattr_from_category(name) File "sage/structure/element.pyx", line 506, in sage.structure.element.Element.getattr_from_category (build/cythonized/sage/structure/element.c:4624) return getattr_from_other_class(self, cls, name) File "sage/cpython/getattr.pyx", line 228, in sage.cpython.getattr.getattr_from_other_class (build/cythonized/sage/cpython/getattr.c:1848) raise AttributeError(dummy_error_message) AttributeError: 'FreeModule_ambient_field_with_category.element_class' object has no attribute 'cross_prodtct'