danielvolinski's profile - activity

Hi All,

I understand that many download mirrors of SageMath for Windows are inactive, they are stuck at SageMath 9.2, no trace of SageMath 9.3 for Windows or SageMath 9.4 for windows. What is the most reliable and active site to download the latest version of SageMath for Windows?

Thanks,

Daniel Volinski

Download Mirrors inactive Hi All, I understand that many download mirrors of SageMath for Windows are inactive, they ar

What I'd suggest now is to put this procedure and knowledge into a command so that there will be no need to do it manually. You will just need to write the Integral Equation and use this new command to obtain the required solution. Daniel Volinski

Thank you,

I was looking for something like what you see in Solve a Volterra Integral Equation , not something manual as you did but a command that would give the solution once I give the equation.

Daniel Volinski

Can Sage solve integral equations (where the unknown is a function and the equation involves integrals), either analytically or numerically?

References:

• Encyclopedia of math: integral equations
• Wikipedia: integral equations

For example, can Sage solve a Volterra equation of the second kind, such as

y(x) == integrate(exp(x-t)*y(t), t, 0, x)

The solution is expected in the form $y(x) = ...$ where the right hand side is an explicit function of $x$ not involving $y$.

Notice in the example the function $y$ appears in two places, once in the left hand side and the other inside the integral sign.

I am looking for something like what you see in

• Wolfram Language: solve a Volterra integral equation

i.e., a command that would give the solution once I give the equation.

Hi All,

Forgive me if this question is not appropriate in this forum.

I have installed and used SageMath 9.1 Native Windows.

I would like to know how to install and use Cadabra2 in a Jupyter Notebook.

Is it possible?

Thanks,

Daniel Volinski

I would go for something more suave, some kind of error that would not stop the calculation of further cells in the notebook, after all, it is not an error that can cause other errors, you just have to give some content to the affine connection (or the tensor field) and everything should be all right.

Hi All,

I'm using SageMath 9.1 on Windows Native.

When affine_connection has no content and I display it, I get a ValueError that stops the computation.

M = Manifold(3, 'M', start_index=1)
c_xyz.<x,y,z> = M.chart()
nab = M.affine_connection('nabla', r'\nabla')
print(nab)
nab.display()

IMO it should display something like 'Empty' or 'Null' or '{}' but not an error.

Daniel

I reported it in sage-support

I reported it in sage-support

In the section "Geometry and Topology" on the page

• https://doc.sagemath.org/pdf/en/reference/

the first link is

:doc:`Euclidean Spaces and Vector Calculus`

which does not link to any file. Please fix this.