伯克利 CS61A 课堂笔记 06 —— Example: Sounds of Wave Files

本系列为加州伯克利大学著名 Python 基础课程 CS61A 的课堂笔记整理，全英文内容，文末附词汇解释。

from wave import open
from struct import Struct
from math import floor

frame_rate = 11025

def encode(x):
    """Encode float x between -1 and 1 as two bytes."""
    i = int(16384 * x)
    return Struct('h').pack(i)

def play(sampler, name = 'song.wav', seconds = 2):
    """Write the output of a sampler function as a wav file."""
    out = open(name, 'wb')
    out.setnchannels(1)
    out.setsampwidth(2)
    out.setframerate(frame_rate)
    t = 0
    while t < seconds * frame_rate:
        sample = sampler(t)
        out.writef