如何将数学方程从函数写入文件？

Question

我正在尝试从文件中统计数据并计算平均值、中位数、最小值和最大值。 我能做到的就这么多了。

我苦苦挣扎的地方是，我需要给用户一个选项，将计算出的统计数据保存到一个新文件中。它给了我一个错误，说'str'对象没有属性'write'

有谁知道我如何将“computed_stats”函数写入文件？ 非常感谢任何帮助！

这是我的大部分代码的屏幕截图。我没有足够的屏幕空间来包含提示用户输入选择的表格或加载数据的函数。对于这个问题，它们似乎并不重要。

def table():
    print("Choose an option:")
    print("1. Load data")
    print("2. Display computed statistics")
    print("3. Save computed statistics")
    print("4. Exit")

def load_data(filename):
    with open(filename) as f:
        for lines in f:
            numbers = lines.split()
            return(numbers)

def compute_stats(data_list):

    minimum = (min(data_list))
    maximum = (max(data_list))
    mean = (sum(data_list) / (len(data_list)))
    data = sorted(data_list)
    if (len(data) % 2) == 1:
        median = data[len(data) // 2]      
    else:
        median = (data[len(data) // 2] + data[len(data) // 2 - 1]) / 2
    return minimum, maximum, mean, median

def print_stats(data_list):
    minumum, maximum, mean, median = compute_stats(data_list)
    print(minimum)
    print(maximum)
    print(mean)
    print(median)


def save_stats(new_file):
    global comp_data    
    with open(new_file, 'w') as f:        
        f.close()



def main():


    selection = 0
    while selection != "4":
        table()
        selection = input("Choose a selection: ")
        print()

        if selection == "1":
            data_list = input("Enter the name of your file: ")
            data_list = load_data(data_list)
            data_list = [int(x) for x in data_list]
            print("Data read sucessfully \n")


        elif selection == "2":          
            print_stats(data_list)


        elif selection == "3":
            new_file = input("Enter File Name")
            save_stats(new_file)


main()

Answer 1

您在这里遇到的一个经典问题是您将结果的表示与计算混为一谈。在您的代码中，computed_stats 函数同时执行打印和计算。顺便说一句，它的名字很糟糕，像print_statistics 这样的东西可能会更好。通常，当您的函数名称不自然地以动词开头时，它们的职责定义不正确。

对于第一次更改，我会这样做：

def compute_statistics(data_list):
    # Do whatever computations you need but don't print anything
    minimum = #Insert computation for minimum here
    maximum = #Insert computation for maximum here
    mean = #Insert computation for mean here
    median = #Insert computation for median here
    return minimum, maximum, mean, median # whatever statistics you are computing

def print_statistics(data_list):
    minimum, maximum, mean, median=compute_statistics(data_list)
    # Put your printing logic here using the results from above

def save_statistics(file_name, data_list):
    minimum, maximum, mean, median=compute_statistics(data_list)
    with open(file_name,'w') as outfile:
        file.write(f"min = {minimum}\n")
        # Put all your saving logic here

如果您希望打印的版本与保存的版本完全相同，您还可以添加一个用于生成该字符串的函数，您可以从print_statistics 和save_statistics 调用该函数。

稍后，您可能希望考虑如何更好地管理应用程序的状态，这样您就不必每次都重新计算统计信息。但那是另一个故事了。