如何将字典写入CSV文件？

Question

尝试将原始csv文件的选定行复制到新的csv文件时，请保持提示错误。我只想将第2列包含“ B”的行复制到新的csv文件中，对于“ M”中的行也类似。我面临的另一个挑战是因为原始CSV文件包含浮点数。

设法重命名我的标头并写入新的csv文件，因为原始标头过于冗长，因此请考虑使用数字重新标记它们以便于调用。

原始csv文件

新的csv文件

import csv

with open("breast_cancer_v1.csv", newline='') as original, open("benign.csv", "w", newline='') as benign:

    fieldnames = ['1', '2','3','4','5','6','7','8','9','10','11']

    writer = csv.DictWriter(benign, fieldnames)

    writer.writeheader()   

    print ("\nColumn \ Description title", "\n1:  ID", "\n2:  Diagnosis", "\n3:  a) radius (mean of distances from center to points on the perimeter)", "\n4:  b) texture (standard deviation of gray-scale values)", "\n5:  c) perimeter", "\n6:  d) area", "\n7:  e) smoothness (local variation in radius lengths)", "\n8:  f) compactness (perimeter^2 / area - 1.0)", "\n9:  g) concavity (severity of concave portions of the contour)", "\n10: h) concave points (number of concave portions of the contour)", "\n11: i) symmetry", "\n12: j) fractal dimension (coastline approximation - 1)")

    csv_file = csv.DictReader(original, fieldnames)

    next(csv_file) 

    col_1 = 3
    col_2 = 4
    B_row_count = 0
    M_row_count = 0
    B_sum = 0
    M_sum = 0

    for row in csv_file:

        if (row['2'] == "B"):

            B_sum += float(row[str(col_1)])
            B_row_count += 1 
            writer.writerow(row)

        elif (row['2'] == "M"):

            M_sum += float(row[str(col_1)])
            M_row_count += 1 

print ("\nNo. of patients (rows) under benign(B) group is: " + str(B_row_count))        
print ("No. of patients (rows) under malignant(M) group is: " + str(M_row_count))   
print ("\nTotal No. of patients (rows) is: " + str(B_row_count + M_row_count))

错误消息为：

回溯（最近一次通话最近）：文件“ C：\ Users \ User \ Desktop \ final coursework \ Final coursework.py”，第69行，在 B_sum + = float（row [str（col_1）]）文件“ C：\ Users \ User \ AppData \ Local \ Programs \ Python \ Python35-32 \ Lib \ csv.py”， 第153行，在writerow中 返回self.writer.writerow（self._dict_to_list（rowdict））文件“ C：\ Users \ User \ AppData \ Local \ Programs \ Python \ Python35-32 \ Lib \ csv.py”， _dict_to_list中的第149行 +“，” .join（[[repr（x）for right_fields中的x]]））buildins.ValueError：dict包含不在字段名中的字段：None