如何在从文本文件中读取时将字符串转换为浮点数

Question

嘿家伙所以我有一个文本文件,我试图从中读取并接收每个数字字符串并将其转换为浮点数.但是每当我尝试它时,它都会说"把绳子转换成浮子".为什么会这样？谢谢!

try:
    input_file = open("Dic9812.TFITF.encoded.txt","r")
    output_fileDec = open("Dic9812.TFITF.decoded.txt","w")
    output_fileLog = open("Dic9812.TFITF.log.txt","w")
except IOError:
    print("File not found!")

coefficientInt = input("Enter a coefficient: ")
coefficientFl = float(coefficientInt)
constInt = input("Enter a constant: ")
constFl = float(constInt)

try:
    for line in input_file:
        for numstr in line.split(","):
            numFl = float(numstr)
            print(numFl)
except Exception as e:
    print(e)

该文件如下所示:

135.0,201.0,301.0
152.0,253.0,36.0,52.0
53.0,25.0,369.0,25.0

它最终打印数字,但最后它说:不能将字符串转换为浮点数:

Answer 1

在第二行的末尾,您有一个逗号,因此列表中有一个空字符串.float('')提出异常,因此你的错误:

for line in input_file:
    for numstr in line.split(","):
        if numstr:
            try:
                numFl = float(numstr)
                print(numFl)
            except ValueError as e:
                print(e)

如评论中所述,避免捕获Exception并尝试在a中使用最小代码行try/except以避免无提示错误.