T(p,q) transforms the pair (a,b) according to a <-- bq + aq + ap and b <-- bp + aq.
Can someone explain how this transformation works?
SICP Exercise 1.19 PQ transformation
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1 Answers
Just as you wrote,
T(p,q)
(a, -----------> ( bq + aq + ap ,
b) bp + aq )
In pseudocode,
T(p,q)(a,b) = ( b*q + a*q + a*p , b*p + a*q )
The transformation T(p,q), given a pair (a,b), calculates two new values,
a2 = b*q + a*q + a*p , and
b2 = b*p + a*q
and then constructs a pair, (a2,b2), and returns it as the result.
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