> if any coefficient is zero (or actually both coefficients (e.g. a1 and a2) are zero?

In order to be collinear

x1==0 <=> x2==0 for all dimensions x

Don't fall into the trap to divide by zero.

It helps envisioning the 3D case, like a1 == b1== 0 means the NV1 is on the Z axis.

This describes a plane parallel to the XY plane.

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

In reply to Re: The intersection of M hyperplanes (Ndim) by LanX
in thread The intersection of M hyperplanes (Ndim) by bliako

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