THE ORIGINAL VIEW OF REED-SOLOMON CODES THE ORIGINAL ...

LAGRANGE INTERPOLATION
For each i 2 S we need a polynomial, i (Z), of
degree M , 1 which has the value 1 at x i and the
value 0 at x j for j 2 S; j 6= i
With these, the solution for P is
P (Z) = X
i2S
r i i (Z)
If r i includes an error e i then e i i (Z) is added
to the correct P (Z).
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