P22課筆記

#主和弦的調(diào)號

mainHeXian = 1

#定義和弦類,實例化后其根音參數(shù)只能輸入A-G的大寫英文字母

class chord():

??def __init__(self,root,**kw):

????self.root = root

????for third,fifth in kw.items():

??????setattr(self,third,fifth)

??def play(self):

????print("該和弦的根音是",self.root)

??def transposition(self): #轉(zhuǎn)調(diào)

????if self.root == mainHeXian:

??????print("可以轉(zhuǎn)到任意一個調(diào),因為整個樂段已經(jīng)回到終止的狀態(tài)")

??????#判斷主和弦的屬和弦

????if self.root == (mainHeXian+4)-7*((mainHeXian+4)//7):

??????print("可以選擇級進(jìn)或跳進(jìn)\n")

??????print("直接轉(zhuǎn)調(diào),在音階中,兩個相鄰的音是級進(jìn),比如do→re,re→mi是級進(jìn)\n")

??????print("跳進(jìn)過渡轉(zhuǎn)調(diào)，在級進(jìn)的基礎(chǔ)上,跳過某個音,比如do→mi]n")

????else:

??????print("萬能轉(zhuǎn)調(diào)")

??#把str類型的根音字母轉(zhuǎn)換到int類型

??def Root_Letter_to_Num(self):

????if self.root == "C": self.intRoot = 1

????if self.root == "D": self.intRoot = 2

????if self.root == "E": self.intRoot = 3

????if self.root == "F": self.intRoot = 4

????if self.root == "G": self.intRoot = 5

????if self.root == "A": self.intRoot = 6

????if self.root == "B": self.intRoot = 7

#萬能轉(zhuǎn)調(diào)函數(shù)

def universal_transposition(later_chord): #參數(shù)當(dāng)中有個chord類

??#先把和弦根音的root轉(zhuǎn)換到整數(shù)

??later_chord.Root_Letter_to_Num()

??GuoDu_chord_root = (later_chord.intRoot+4)-7*((later_chord.intRoot+4)//7)

??print("過渡和弦是",GuoDu_chord_root,"和弦")

#定義減七和弦法

def reduce7_Chord(later_chord):

??GuoDu_chord_root = "#"+later_chord.root

??print("過渡和弦是", GuoDu_chord_root,"和弦")

C = chord("C",third="E",fifth="G")

C.play()

print("C和弦的三音是",C.third,",五音是",C.fifth)

#測試萬能轉(zhuǎn)調(diào)，假設(shè)后面的和弦是F和弦

F = chord("F")

universal_transposition(F)

#測試減七和弦法，假設(shè)后面的和弦是A和弦

A = chord("A")

reduce7_Chord(A)

-----------------------------------以上為python代碼

測試結(jié)果為

該和弦的根音是 C

C和弦的三音是 E ,五音是 G

過渡和弦是 1 和弦

過渡和弦是 #A 和弦

---------------------------------這篇學(xué)完后瞬感自己tobyfox、2un附體