"SICP Exercise" 9 Exercise 1.15



(define (Cube x) (* x x x))

(define (P x) (-(* 3 x) (* 4 (Cube x)))

(Define (sine angle)

(if (Not (> (ABS angle) 0.1))

Angle

(P (sine (/angle 3.0))))

The code in the topic is written to Edwin , and trace can be used to trace P 's call, which is available in Visual Studio , and I've only recently known trace the.

(TRACE-ENTRYP)

; Unspecifiedreturn value

(sine12.15)

[Entering#[compound-procedure P]

Args:4.9999999999999996e-2]

[Entering#[compound-procedure P]

Args:. 1495]

[Entering#[compound-procedure P]

Args:. 4351345505]

[Entering#[compound-procedure P]

Args:. 9758465331678772]

[Entering#[compound-procedure P]

Args:-.7895631144708228]

; value:-.39980345741334

Thus it appears that p has run altogether 5 times.

Everyone should have seen it. The sine process is a recursive, so its time and space complexity are O (Loga). The number of times thep is run is incremented whenever the parameter a in the title is multiplied by 3 . You can have a happy test with trace .

"SICP Exercise" 9 Exercise 1.15