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產生sine wave 波型與聲音
Example Code

import wave

import numpy as np

import matplotlib.pyplot as plt

time = 1 # second 聲音播放時間

framerate = 44100 # 聲音取樣率

nframes = time * framerate # 多少個數據點

n = np.arange(0, time, 1/framerate) #產生播放時間內的時間軸數列

f_Do =262 # Hz # Do 的頻率; f_Mi =330 # Hz; f_Sol =392 # Hz ;f_HDo =523 # Hz

sinus_f_Do = np.sin(2*np.pi*f_Do*n) #以sine wave產生波型數據, 產生t秒 44.1kHz取樣率音高是Do的 sine wave

#sinus_f_Do = np.append(sinus_f_Do, sinus_f_Mi) #新增sine wave波型數據, 新產生t秒 44.1kHz取樣率音高是Mi的 sine wave, 並合併資料

#sinus_f_Do = np.append(sinus_f_Do, sinus_f_Sol) #新增sine wave波型數據, 新產生t秒 44.1kHz取樣率音高是Sol的 sine wave, 並合併資料

#sinus_f_Do = np.append(sinus_f_Do, sinus_f_HDo) #新增sine wave波型數據, 新產生t秒 44.1kHz取樣率音高是High Do的 sine wave, 並合併資料

# 先放大以免轉換 np.short 為 0，並且聲音過大或過小, 在此我先歸一化聲波的振幅爲10000,（請由小數值測試起, 以免喇叭損壞）

volume = max([sinus_f_Do.max(), -sinus_f_Do.min()])

volumeLimit = 10000/volume

wave_data = sinus_f_Do * volumeLimit

wave_data = wave_data.astype(np.short)

# 寫入檔案

f = wave.open(r"sweepDoMiSol.wav", "wb")

# 設定聲道數、sample 大小(byte) 和取樣頻率

f.setnchannels(1)

f.setsampwidth(2)

f.setframerate(framerate)

# 寫入波形數據

f.writeframes(wave_data.tostring())

f.close()

Note and Comments
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畫出上例的 262Hz sine wave

畫出上例的 262Hz sine wave
Example Code

import numpy as np

import matplotlib.pyplot as plt

import matplotlib.pyplot as plt;

plt.plot(n[0:300], sinus_f_Do[0:300]);

plt.show()

Note and Comments
result

畫出上例的 262Hz sine wave 與Mi

畫出上例的 sine wave
Example Code

import numpy as np;

import matplotlib.pyplot as plt;

sinus_f_Do = np.sin(2*np.pi*f_Do*n)

plt.plot(n[0:800], sinus_f_Do[0:800],'--');

f_Mi =330

sinus_f_Mi = np.sin(2*np.pi*f_Mi*n)

plt.plot(n[0:800], sinus_f_Mi[0:800],'--');

sinus_f_Do=sinus_f_Do+sinus_f_Mi

volume = max([sinus_f_Do.max(), -sinus_f_Do.min()])

volumeLimit = 1/volume

sinus_f_Do=sinus_f_Do*volumeLimit

plt.plot(n[0:800], sinus_f_Do[0:800]);

plt.legend(['Do 262 Hz','Mi','Do + Mi'])

plt.show()

Note and Comments
result

畫出上例的 Do, Mi, & Sol

畫出上例的 Do, Mi, & Sol
Example Code

import numpy as np;

import matplotlib.pyplot as plt;

sinus_f_Do = np.sin(2*np.pi*f_Do*n)

plt.plot(n[0:1200], sinus_f_Do[0:1200],'--');

f_Mi =330

f_Sol =392

sinus_f_Do=sinus_f_Do +np.sin(2*np.pi*f_Mi*n) +np.sin(2*np.pi*f_Sol*n)

volume = max([sinus_f_Do.max(), -sinus_f_Do.min()])

volumeLimit = 1/volume

sinus_f_Do=sinus_f_Do*volumeLimit

plt.plot(n[0:1200], sinus_f_Do[0:1200],'r');

plt.legend(['Do 262 Hz','Do + Mi + Sol'])

plt.show()

Note and Comments
result