從文件中讀取Python的矩陣

Question

這是爲了我的IT類，我試圖找出每一行的總和。它是一個神奇的廣場節目。當我運行這個它說int對象不可迭代。另外，老師需要這個函數的頭像def rowSum（matrix，rowNum），但我不明白爲什麼需要rowNum。該函數應該能夠計算任意大小矩陣的每一行的總和。此外，我不能使用numpy和enumarate，因爲我們還沒有在課堂上討論過它。

矩陣txt文件：

1 4 
3 2 

這裏是代碼

def main(): 
    filNam = "matrix1.txt" 
    matrix = (readMatrix(filNam)) 
    print(eachNumPresent(matrix)) 
    print(rowSum(matrix)) 

def readMatrix(filNam): 
    matrixFile = open(filNam, "r") 
    line = matrixFile.readline() 
    for line in matrixFile: 
     line = line.split() 
    return line 
    matrixFile.close() 

def eachNumPresent(matrix): 
    if len(matrix) % 2 == 0: 
     return True 
    else: 
     print("Not enough numbers") 

def rowSum(matrix, rowNum): 
    for line in matrix: 
     return(sum(int(line))) 

main() 

Answer 1

這個怎麼樣，它假定，當你想在第一行，你輸入「0」，如果你想在第二行你會輸入'1'等等...很容易改變。

def main(): 
    fn = "matrix1.txt" 
    matrix = readMatrix(fn) 
    n = int(input("Enter row number: ")) 
    rowSum(matrix, n) 

def readMatrix(fn): 
    matrix = [] 
    with open(fn) as f: # a with block will auto close your file after the statements within it 
     for line in f: 
      line = line.strip() # strip off any trailing whitespace(including '\n') 
      matrix.append(line.split()) 
    return matrix 

def rowSum(matrix, rowNum): 
    result = sum(int(i) for i in matrix[rowNum]) 
    print("The sum of row {} = {}".format(rowNum, result)) 

main() 

輸出示例：

The sum of row 1 = 5 

編輯：

要計算列的總和：

def main(): 
    fn = "matrix1.txt" 
    matrix = readMatrix(fn) 
    n = int(input("Enter col number: ")) 
    colSum(matrix, n) 

def readMatrix(fn): 
    matrix = [] 
    with open(fn) as f: # a with block will auto close your file after the statements within it 
     for line in f: 
      line = line.strip() # strip off any trailing whitespace(including '\n') 
      matrix.append(line.split()) 
    return matrix 

def colSum(matrix, colNum): 
    result = sum(int(row[colNum]) for row in matrix) 
    print("The sum of col {} = {}".format(colNum, result)) 

main() 

Answer 2

1.you可以學習大熊貓

2。她的代碼有錯誤e是我的代碼

def main(): 
    filNam = "matrix1.txt" 
    rowNum, matrix = (readMatrix(filNam)) 
    print(eachNumPresent(rowNum)) 
    rowSum(matrix) 

def readMatrix(filNam): 
    matrix_list = [] 
    total_num = 0 
    with open(filNam, 'r') as matrixFile: 
     for line in matrixFile.readlines(): 
      line = line.split() 
      line = [int(i) for i in line] 
      matrix_list.append(line) 
      total_num += len(line) 
    return total_num, matrix_list 

def eachNumPresent(num): 
    if num % 2 == 0: 
     return True 
    else: 
     print("Not enough numbers") 

def rowSum(matrix): 
    for row in matrix: 
     print sum(row) 

main() 

出來：

True 
5 
5 

Answer 3

你不是遍歷正確順序，您用來代替「readlines方法」「的ReadLine」，其中只讀的線路之一矩陣，而不是完整的文件。你想要做的是讀取所有行，並將這些行轉換爲列表，所以你可以使用sum（）。請注意，拆分之後，您需要確保將結果字符串轉換爲int。通過這種方式，您可以將矩陣形成列表列表（格式[[1,2]，[3,4]]），然後您可以將行號（從零開始，但可以調整）傳遞給rowSum方法（這就是爲什麼你的老師給你這種格式的原因）

看到更正後的例子中的差異（例如我在不同的操作中給出了轉換的步驟，但你實際上可以重構該代碼來獲得它做更少的行）：

def main(): 
    filNam = "matrix1.txt" 
    matrix = (readMatrix(filNam)) 
    print(eachNumPresent(matrix)) 
    print(rowSum(matrix, 0)) 

def readMatrix(filNam): 
    with open(filNam, 'r') as matrixFile: 
     matrix = [] 
     lines = matrixFile.readlines() 
     for line in lines: 
      items = line.split() 
      numbers = [int(item) for item in items] 
      print numbers 
      matrix.append(numbers) 
     return matrix 

def eachNumPresent(matrix): 
    if len(matrix) % 2 == 0: 
     return True 
    else: 
     print("Not enough numbers") 

def rowSum(matrix, rowNum): 
    for line in matrix: 
     return(sum(line)) 

main() 

如果您需要任何澄清只是讓我知道...希望它有幫助！