Python + 不支持的操作数类型：“float”和“str”错误
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Unsupported operand type(s) for +: 'float' and 'str' error
提问by Usman Khan
I am new to Python and am stuck with what to do right now because I keep getting this error. I am trying to add the contents of the score file together and get an average but I can't seem to get it to work.
我是 Python 的新手，并且坚持现在要做的事情，因为我不断收到此错误。我试图将分数文件的内容加在一起并获得平均值，但我似乎无法让它工作。
My code:
我的代码：
# open and read file student / score
student_file = open("Student.txt", "r")
score_file = open("Score.txt", "r")
student = student_file.read().split(' ')
score = score_file.read().split(' ')
addedScore = 0.0
average = 0.0
for i in range(0,len(student)):
print("Student: "+student[i]+" Final: "+score[i])
addedScore = addedScore + score[i]
average = addedScore / 2
print("The class average is:", average)
The score file is full of float numbers:
分数文件充满了浮点数：
90.0 94.0 74.4 63.2 79.4 87.6 67.7 78.1 95.8 82.1
The error message
错误信息
line 12, in <module>
addedScore = addedScore + score[i]
TypeError: unsupported operand type(s) for +: 'float' and 'str'
I appreciate all the help I can get. Thanks a lot
我很感激我能得到的所有帮助。非常感谢
采纳答案by Scott Hunter
Since scorewas created by splitting a string, it's elements are all strings; hence the complaint about trying to add a float to a string. If you want the value that that string represents, you need to compute that; something like float(score[i]).
由于score是通过拆分字符串创建的，所以它的元素都是字符串；因此，关于尝试向字符串添加浮点数的抱怨。如果您想要该字符串表示的值，则需要计算它；类似的东西float(score[i])。
回答by ForceBru
scoreis a list of strings, so you definitely cannot add a string to a float as you do here: addedScore = addedScore + score[i]. You have to convert this string to a float: addedScore = addedScore + float(score[i])
score是一个字符串列表，因此您绝对不能像此处那样将字符串添加到浮点数：addedScore = addedScore + score[i]。您必须将此字符串转换为浮点数：addedScore = addedScore + float(score[i])
回答by zondo
When you split the contents of the file, they are still strings. Change score = score_file.read().split(' ')to score = [float(x) for x in score_file.read().split(" ")]. You probably don't need to do .split(" "), because str.split()will by default split by whitespace. Therefore, you can use .split().
当您拆分文件的内容时，它们仍然是字符串。更改score = score_file.read().split(' ')为score = [float(x) for x in score_file.read().split(" ")]。你可能不需要做.split(" ")，因为str.split()默认情况下会被空格分割。因此，您可以使用.split().
