[Jprogramming] A plane rotation

[Michal Wallace]

rot =: [: +. (%|)@[ * j./@]

On Tue, Feb 16, 2016 at 4:12 PM, Kip Murray <thekipmurray at gmail.com> wrote:

> Another example
>
>     0j2 rot 3 4
>  _4 3
>
> This rotates 3 4 by 90 degrees, counterclockwise.
>
> --Kip
>
>
> On Tuesday, February 16, 2016, Kip Murray <thekipmurray at gmail.com> wrote:
>
> > Fairly easy: write a verb that rotates a point in the plane by the angle
> > of a given complex number.  For example
> >
> >     1j1 rot 1 1  NB. Rotate 1 1 counterclockwise 45 degrees
> >  0 1.414213562
> >
> > Background information:  when you multiply two complex numbers the
> > magnitudes are multiplied and the angles are added.
> >
> > --Kip Murray
> >
> >
> >
> > --
> > Sent from Gmail Mobile
> >
>
>
> --
> Sent from Gmail Mobile
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