數學建模之Python操做csv文件

1.用Python經過csv文件裏面的某一列，造成鍵值，而後統計鍵在其餘列出現的次數。

import pandas as pd
import numpy as np
import csv
import codecs
import sys

data_original = pd.read_csv('D:/csv_data_original.csv')
data = pd.read_csv('D:/week1.csv')
#data = data['retweeted_status_mid'].fillna('NOT PROVIDED',inplace=True)
#data_transpond = data[data['retweeted_status_mid'] != 'NOT PROVIDED']

#每條原創微博轉發次數統計
def statistics(path1,path2):
    num1 = 0
    num2 = 0
    #這塊代碼用來造成鍵值，初始化爲0
    with open(path2, 'r', encoding="iso-8859-1") as f:
        reader2 = csv.reader(f)
        data_head2 = next(reader2)
        print(data_head2)
        data_line = next(reader2)
        while(data_line):
            if data_line[0] not in mid.keys():
                mid[data_line[0].encode("iso-8859-1").decode("gbk", "ignore")] = 0
                num2 += 1
                print("正在建立第" + str(num2) + "個鍵")
            try:
                data_line = next(reader2)
            except StopIteration:
                print("數據處理完畢，鍵值徹底造成" + str(num2) + "!")
                break
                #sys.exit()
        f.close()
    #這塊代碼用來統計每一個鍵出現的次數
    with open(path1, 'r', encoding="iso-8859-1") as f:
        reader1 = csv.reader(f)
        data_head1 = next(reader1)
        print(data_head1)
        data_line = next(reader1)
        while(data_line):
            if data_line[1] in mid.keys():
                mid[data_line[1].encode("iso-8859-1").decode("gbk", "ignore")] += 1
                print("這條微博被轉發" + str(mid[data_line[1]]) + "次")
            try:
                data_line = next(reader1)
            except StopIteration:
                print("數據處理完畢，轉發次數統計完畢")
                break
                #sys.exit()
        f.close()
#字典轉化爲列表
def transpond(dict):
    global list_key#保存鍵
    global list_value#保存值
    list_key = list(dict)
    list_value = list(dict.values())


#將數據寫入csv文件
def data_write_csv(file_name, list1,list2):#file_name爲寫入CSV文件的路徑，datas爲要寫入數據列表
    with open(file_name,'w',newline='') as f:
        writer = csv.writer(f)
        writer.writerows(zip(list1, list2))


if __name__ == "__main__":
    path_data = 'D:/week1.csv'  # 原始數據路徑
    path_data_original = 'D:/csv_data_original.csv'  # 處理後只含原創的微博數據路徑
    path_save = 'D:/transpond_data.csv'  # 保存處理後的數據
    mid = {}  # 定義字典用來保存每條原創微博被轉發的次數
    list_key = []  # 保存鍵
    list_value = []  # 保存值
    statistics(path_data,path_data_original)
    transpond(mid)
    data_write_csv(path_save,list_key,list_value)

2.與1相似的操做，具體有一些細節變更，代碼中有註釋

import csv
import pandas as pd

#每條原創微博轉發次數統計
def statistics(path1,path2):
    num2 = 0
    #這塊代碼用來造成鍵值，初始化爲0
    with open(path2, 'r', encoding="iso-8859-1") as f:
        reader2 = csv.reader(f)
        data_head2 = next(reader2)
        print(data_head2)
        data_line = next(reader2)
        while(data_line):
            if data_line[0] not in mid.keys():
                mid[data_line[0].encode("iso-8859-1").decode("gbk", "ignore")] = 0
                num2 += 1
                print("正在建立第" + str(num2) + "個鍵")
            try:
                data_line = next(reader2)
            except StopIteration:
                print("數據處理完畢，鍵值徹底造成" + str(num2) + "!")
                break
                #sys.exit()
        f.close()
    #這塊代碼用來統計每一個鍵出現的次數
    with open(path1, 'r', encoding="iso-8859-1") as f:
        reader1 = csv.reader(f)
        data_head1 = next(reader1)
        print(data_head1)
        data_line = next(reader1)
        while(data_line):
            if data_line[2] in mid.keys():
                mid[data_line[2].encode("iso-8859-1").decode("gbk", "ignore")] += int(data_line[1])
                print("這個用戶的微博被轉發一共" + str(mid[data_line[2]]) + "次")
            try:
                data_line = next(reader1)
            except StopIteration:
                print("數據處理完畢，轉發次數統計完畢")
                break
                #sys.exit()
        f.close()

#字典轉化爲列表
def transpond(dict):
    global list_key#保存鍵
    global list_value#保存值
    list_key = list(dict)
    list_value = list(dict.values())

#將數據寫入csv文件
def data_write_csv(file_name, list1,list2):#file_name爲寫入CSV文件的路徑，datas爲要寫入數據列表
    with open(file_name,'w',newline='') as f:
        writer = csv.writer(f)
        writer.writerows(zip(list1, list2))

if __name__ == '__main__':
    path1 = 'D:/csv_data_original_num.csv'  # 用來造成鍵的數據路徑
    path2 = 'D:/data_all.csv'  # 用來查找鍵值的數據路徑
    path_save = 'D:/user_transpond.csv'  # 存放統計好的數據路徑
    mid = {}
    list_key = []
    list_value = []
    statistics(path2,path1)
    transpond(mid)
    data_write_csv(path_save,list_key,list_value)

3.將大數據的csv文件根據特定條件分紅幾份小文件

#coding = utf-8
import pandas as pd
import csv


def get_txt(path1,path2,path3,path4,path5,path6,path7,path8):
    num = 0
    with open(path1, 'r',encoding = 'utf-8') as f:
        txt1 = open(path2, "w", encoding='utf-8')
        txt2 = open(path3, "w", encoding='utf-8')
        txt3 = open(path4, "w", encoding='utf-8')
        txt4 = open(path5, "w", encoding='utf-8')
        txt5 = open(path6, "w", encoding='utf-8')
        txt6 = open(path7, "w", encoding='utf-8')
        txt7 = open(path8, "w", encoding='utf-8')
        reader1 = csv.reader(f)
        data_head1 = next(reader1)
        print(data_head1)
        data_line = next(reader1)
        while(data_line):
            num += 1
            print(num)
            print(data_line[6])
            if num > 0 and num < 700000:
                txt1.write(data_line[6] + '\n')
            elif num >= 700000 and num < 1400000:
                txt2.write(data_line[6] + '\n')
            elif num >= 1400000 and num < 2100000:
                txt3.write(data_line[6] + '\n')
            elif num >= 2100000 and num < 2800000:
                txt4.write(data_line[6] + '\n')
            elif num >= 2800000 and num < 3500000:
                txt5.write(data_line[6] + '\n')
            elif num >= 3500000 and num < 4200000:
                txt6.write(data_line[6] + '\n')
            elif num >= 4200000 and num < 4700000:
                txt7.write(data_line[6] + '\n')
            try:
                data_line = next(reader1)
            except StopIteration:
                print("數據處理完畢，轉發次數統計完畢")
                break
                #sys.exit()
        f.close()
if __name__ == '__main__':
    path1 = 'D:/week1.csv'
    path2 = 'D:/text1.txt'
    path3 = 'D:/text2.txt'
    path4 = 'D:/text3.txt'
    path5 = 'D:/text4.txt'
    path6 = 'D:/text5.txt'
    path7 = 'D:/text6.txt'
    path8 = 'D:/text7.txt'
    get_txt(path1,path2,path3,path4,path5,path6,path7,path8)