w3school字串str，format，len，slicing[::]

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程式碼註解

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  6月 26, 2025 Python 函數def 函數名稱: def draw(): canvas繪圖套件 create_line(x起點,y起點,x終點,y終點) def draw第二個delete def draw():#按下按鈕button1執行draw canvas.create_line(0,500,700,500,width=3,fill='black',arrow='last') canvas.create_line(10,600,10,5,width=3,fill='black',arrow='last') for firm in firms: t=(firm, year.get()) x = 10+20*stdev[t]*2*3**0.5 #放大20 y = 500 - 10*mean[t]*12 #放大10 dot=canvas.create_oval(x-5,y-5,x+5,y+5,fill='blue') lab=canvas.create_text(x+10,y,text=firm[4:7],anchor=W,font=('微軟中黑體', 16)) def delete():#按下按鈕button2執行delete canvas.delete('all') years=[x for x in range(2007, 2025)] year=IntVar(tk) year.set(years[0]) label = Label(tk, text="年度",font=('Arial',30,'bold'),).pack(side=LEFT) #距離左側 option1 = OptionMenu(tk, year, *years).pack(side=LEFT) button1 = Button(tk, text="賴青德繪圖 ",font=('Arial',30,'bold'), command = draw, bg...
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馬可維茲風險平均數平面

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  6月 12, 2025 https://drive.google.com/file/d/1DEfDy4-l1ikSiOpCNR6SZR7iRB5fvIbt/view?usp=drive_link 6/20程式碼 import csv #輸入csv套件comma separated value f = open('200201to202505.csv','r', encoding="utf-8")#打開下載的檔案SPY.CSV,模式是r讀取, csvreader = csv.reader(f) #將檔案讀入變數csvreader header, rows = list(), list() #宣告空白串列(陣列,清單) firms = set() #建構集合 header = next(csvreader) #串列header儲存檔案第一列 for record in csvreader: #檔案紀錄，逐列row檢視 rows.append(record) #第i筆附加append於rows串列成為rows[i] firms.add(record[0]) #row[0]公司名稱 f.close() #關閉檔案 months = dict() for year in range(2007,2026): months[year]=[str(year*100+month) for month in range(1,13)] count, sum, sumSq, mean, stdev = dict(), dict(), dict(), dict(), dict() for firm in firms: for year in range(2007, 2026): t = (firm, year) #元組(公司,年) count[t] = 0 sum[t] = 0.0 su...
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