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Javier
Posts:
61
Registered:
4/26/11


Re: Find the correspondent coordinates of a unit sphere in a sphere of radius X
Posted:
Dec 3, 2012 8:05 AM


"Roger Stafford" wrote in message <k9g5pg$g8d$1@newscl01ah.mathworks.com>... > "Javier " <javsanzperez@gmail.com> wrote in message <k9fj58$j44$1@newscl01ah.mathworks.com>... > > ..... find the correspondent coordinates of a unit sphere in a sphere of radius X. ...... >           > Let P1 = (x1;y1;z1] be the coordinates of some point on a sphere of radius R1 with center located at C1 = [u1;v1;w1] and let P2 = [x2;y2;z2] be the coordinates of the corresponding point on a sphere of radius R2 with center at C2 = [u2;v2;w2]. Then P2 can be expressed in terms of P1 by the vector equation: > > P2 = C2 + (R2/R1)*(P1C1); > > This amounts to a translation from center C1 to center C2 followed by an expansion by the ratio R2/R1, and, as you see, it is a linear expression. > > Roger Stafford
Thanks very much, Roger!



