Matrix triangular parameter not working

[Shnku]

In js-side it is isMirrored property but in python-side it is triangular property ..
they are not synced .. thats why not working.

[Shnku]

Also, it would be preferable to discuss these things in issues first, before working on an implementation, just to confirm that I agree with the direction of the feature.

It's much easier to maintain a package that way, especially because it seems that the triangular setting is broken.

I changed mirror to triangular (as it is in doc string)
@koaning sir, naming symmetric will be better . It actually creates a symmetric matrix
?? #26