python获取csv后几行 python读取csv前几行

import csv
import pandas as pd
import numpy as np

# 这是表示读取前10行
# d = pd.read_csv(file, usecols=['avg_test_acu','avg_test_prec', 'avg_test_TPR', 'avg_test_FPR', 'avg_train_acu'], nrows=10)
k=0
results=[]
with open(file, 'r', newline='', errors='ignore') as f:
    reader = csv.reader(f)
    for index, rows in enumerate(reader):#index从0开始
        if index == 6+k*11 or index == 7+k*11 or index == 8+k*11 or index == 9+k*11 or index == 10+k*11:#目标行
            if index%11==6:#第一折
                a=[]
                a.append(rows)
            elif index % 11 == 10:  # 最后一折
                a.append(rows)
                k=k+1
                results.append(np.array(a))
            else:
                a.append(rows)

results=np.array(results).astype(float)#直接读取的数据是str 转float