df.to_csv为什么只能显示632行的数据

from PyQt5 import QtWidgets
from PyQt5.QtWidgets import QFileDialog
import csv
import pandas as pd

class MyWindow(QtWidgets.QWidget):
    def __init__(self):
        super(MyWindow, self).__init__()
        self.myButton = QtWidgets.QPushButton(self)
        self.myButton.setObjectName("myButton")
        self.myButton.setText("Test")
        self.myButton.clicked.connect(self.msg)

    def msg(self):
        fileName, filetype = QFileDialog.getOpenFileName(self,
                                                          "选取文件",
                                                          "./",
                                                          "All Files (*);;Text Files (*.txt)")  # 设置文件扩展名过滤,注意用双分号间隔
        print(fileName)
        out = open('fileName.csv', 'w', newline='')
        csv_writer = csv.writer(out, dialect='excel')
        f = open(fileName, "r")
        for line in f.readlines():
            line = line.replace(',', '\t')  # 将每行的逗号替换成空格
            list = line.split()  # 将字符串转为列表，从而可以按单元格写入csv
            csv_writer.writerow(list)

        #writer = csv.writer(fileName, lineterminator='\n')

        df = pd.read_csv('fileName.csv')
        df.to_csv('fileName.csv', index=False)
        print(df)

if __name__ == "__main__":
    import sys

    app = QtWidgets.QApplication(sys.argv)
    myshow = MyWindow()
    myshow.show()
    sys.exit(app.exec_())

from PyQt5 import QtWidgets
from PyQt5.QtWidgets import QFileDialog
import csv
import pandas as pd

class MyWindow(QtWidgets.QWidget):
    def __init__(self):
        super(MyWindow, self).__init__()
        self.myButton = QtWidgets.QPushButton(self)
        self.myButton.setObjectName("myButton")
        self.myButton.setText("Test")
        self.myButton.clicked.connect(self.msg)

    def msg(self):
        fileName, filetype = QFileDialog.getOpenFileName(self,
                                                          "选取文件",
                                                          "./",
                                                          "All Files (*);;Text Files (*.txt)")  # 设置文件扩展名过滤,注意用双分号间隔
        print(fileName)
        out = open('fileName.csv', 'w', newline='')
        csv_writer = csv.writer(out, dialect='excel')
        f = open(fileName, "r")
        for line in f.readlines():
            line = line.replace(',', '\t')  # 将每行的逗号替换成空格
            list = line.split()  # 将字符串转为列表，从而可以按单元格写入csv
            csv_writer.writerow(list)

        #writer = csv.writer(fileName, lineterminator='\n')

        df = pd.read_csv('fileName.csv')
        df.to_csv('fileName.csv', index=False)
        print(df)



if __name__ == "__main__":
    import sys

    app = QtWidgets.QApplication(sys.argv)
    myshow = MyWindow()
    myshow.show()
    sys.exit(app.exec_())

用

df = pd.read_csv('fileName.csv')

df.to_csv('fileName.csv', index=False)

print(df)

的原因是我需要删除.csv文件里面的空白行，确实可行，不过只能删除633行空白行，后面的空白行没有删除，在pycharm界面也没有显示后面的了

基本0基础，希望大佬能够直接改好 多次实验 知道问题就出在

df.to_csv('fileName.csv', index=False)

但不知道怎么改