Ciro Santilli @cirosantilli  40

See: internal and spacetime symmetries.

See: internal and spacetime symmetries.

Ah, the choice of name, both grim and slightly funny, Dr. Strangelove comes to mind quite strongly. Also Fallout (franchise).

Bibliography:

"Intel Research Lablets", that's a terrible name.

There's a tiny little crosshair that you can drag around to set the center of rotation.

And there's a button to make that crosshair snap: inkscape.org/forums/questions/can-a-pivotingtransfrom-crosshair-be-moved-and-made-to-snap-to-a-node-or-a-grid-point/#c14432

This is related to the underlying SVG pain point of SVG background color:

For PNG export:

Given a matrix $A$ with metric signature containing $m$ positive and $n$ negative entries, the indefinite orthogonal group is the set of all matrices that preserve the associated bilinear form, i.e.:Note that if $A=I$, we just have the standard dot product, and that subcase corresponds to the following definition of the orthogonal group: Section "The orthogonal group is the group of all matrices that preserve the dot product".

As shown at all indefinite orthogonal groups of matrices of equal metric signature are isomorphic, due to the Sylvester's law of inertia, only the metric signature of $A$ matters. E.g., if we take two different matrices with the same metric signature such as:and:both produce isomorphic spaces. So it is customary to just always pick the matrix with only +1 and -1 as entries.

Like the special orthogonal group is to the orthogonal group, $SO(m,n)$ is the subset of $O(m,n)$ with determinant equal to exactly 1.

This is a bit harder than iterative pre-order: now we have to check if there is a left or right element or not:

The control flow can be slightly simplified if we allow NULLs: www.geeksforgeeks.org/inorder-tree-traversal-without-recursion/