◄Summary►  ◄Timings►
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Y log(sub2)(X)
 
Syntax:  FYL2X
 
Calculates Z = Y log(sub2)(X). X is taken from ST and Y from ST(1). The
stack is popped and the result, Z, replaces Y in ST. X must be in the
range 0 < X < ∞ and Y in the range -∞ < Y < ∞.
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