pandas有强大的excel数据处理和导入处理功能,本文简单介绍pandas在csv和excel等格式方面处理的应用及绘制图表等功能。
pandas处理excel依赖xlutils, OpenPyXL, XlsxWriter等库。
python处理excel库的参考:https://github.com/xurongzhong/mobile_data
本文代码地址:https://github.com/xurongzhong/mobile_data/tree/master/pandas/excel_demo
本文最新版本地址:http://dwz.cn/7ig569
淘宝天猫可以把链接发给qq850766020,为你生成优惠券,降低你的购物成本!
快来领取支付宝跨年红包!1月1日起还有机会额外获得专享红包哦!复制此消息,打开最新版支付宝就能领取!2C56CV70sA
更多参考资料:
https://www.dataquest.io/blog/excel-and-pandas/
Using Pandas to Read Large Excel Files in Python 中文
CSV
使用pandas读写csv
pandas_parsing_and_write.py
import pandas as pd input_file = r"supplier_data.csv" output_file = r"output_files\1output.csv" data_frame = pd.read_csv(input_file) print(data_frame) data_frame.to_csv(output_file, index=False)
当然也可以用python实现:
1csv_simple_parsing_and_write.py
input_file = r"supplier_data.csv" output_file = r"output_files\1output.csv" with open(input_file, newline='') as filereader: with open(output_file, 'w', newline='') as filewriter: for row in filereader: filewriter.write(row)
2csv_reader_parsing_and_write.py
import csv input_file = r"supplier_data.csv" output_file = r"output_files\2output.csv" with open(input_file, 'r', newline='') as csv_in_file: with open(output_file, 'w', newline='') as csv_out_file: filereader = csv.reader(csv_in_file, delimiter=',') filewriter = csv.writer(csv_out_file, delimiter=',') for row_list in filereader: filewriter.writerow(row_list)
过滤特定行
pandas_value_meets_condition.py
import pandas as pd input_file = r"supplier_data.csv" output_file = r"output_files\3output.csv" data_frame = pd.read_csv(input_file) data_frame['Cost'] = data_frame['Cost'].str.strip('$').astype(float) data_frame_value_meets_condition = data_frame.loc[(data_frame['Supplier Name']\ .str.contains('Z')) | (data_frame['Cost'] > 600.0), :] data_frame_value_meets_condition.to_csv(output_file, index=False)
注意pandas的strip连里面的内容都可以清除, 有点类似replace的功能。
选择日期为'1/20/14', '1/30/14'的行
import pandas as pd input_file = r"supplier_data.csv" output_file = r"output_files\4output.csv" data_frame = pd.read_csv(input_file) important_dates = ['1/20/14', '1/30/14'] data_frame_value_in_set = data_frame.loc[data_frame['Purchase Date']\ .isin(important_dates), :] data_frame_value_in_set.to_csv(output_file, index=False)
pandas_value_matches_pattern.py
import pandas as pd input_file = r"supplier_data.csv" output_file = r"output_files\4output.csv" data_frame = pd.read_csv(input_file) data_frame_value_matches_pattern = data_frame.ix[data_frame['Invoice Number']\ .str.startswith("001-"), :] data_frame_value_matches_pattern.to_csv(output_file, index=False)
过滤特定列
pandas_column_by_index.py
import pandas as pd import sys input_file = r"supplier_data.csv" output_file = r"output_files\6output.csv" data_frame = pd.read_csv(input_file) data_frame_column_by_index = data_frame.iloc[:, [0, 3]] data_frame_column_by_index.to_csv(output_file, index=False)
pandas_column_by_index.py
import pandas as pd input_file = r"supplier_data.csv" output_file = r"output_files\7output.csv" data_frame = pd.read_csv(input_file) data_frame_column_by_name = data_frame.loc[ :, ['Invoice Number', 'Purchase Date']] data_frame_column_by_name.to_csv(output_file, index=False)
pandas_select_contiguous_rows.py
import pandas as pd input_file = r"supplier_data_unnecessary_header_footer.csv" output_file = r"output_files\11output.csv" data_frame = pd.read_csv(input_file, header=None) data_frame = data_frame.drop([0,1,2,16,17,18]) data_frame.columns = data_frame.iloc[0] data_frame = data_frame.reindex(data_frame.index.drop(3)) data_frame.to_csv(output_file, index=False)
添加行头
pandas_add_header_row.py
import pandas as pd input_file = r"supplier_data_no_header_row.csv" output_file = r"output_files\11output.csv" header_list = ['Supplier Name', 'Invoice Number', \ 'Part Number', 'Cost', 'Purchase Date'] data_frame = pd.read_csv(input_file, header=None, names=header_list) data_frame.to_csv(output_file, index=False)
合并多个文件
pandas_concat_rows_from_multiple_files.py
import pandas as pd import glob import os input_path = r"D:\code\foundations-for-analytics-with-python\csv" output_file = r"output_files\12output.csv" all_files = glob.glob(os.path.join(input_path,'sales_*')) all_data_frames = [] for file in all_files: data_frame = pd.read_csv(file, index_col=None) all_data_frames.append(data_frame) data_frame_concat = pd.concat(all_data_frames, axis=0, ignore_index=True) data_frame_concat.to_csv(output_file, index = False)
求和和求平均值
pandas_sum_average_from_multiple_files.py
import pandas as pd import glob import os input_path = r"D:\code\foundations-for-analytics-with-python\csv" output_file = r"output_files\12output.csv" all_files = glob.glob(os.path.join(input_path,'sales_*')) all_data_frames = [] for input_file in all_files: print(input_file) data_frame = pd.read_csv(input_file, index_col=None) print(data_frame) sales = pd.DataFrame([float(str(value).strip('$').replace(',','')) for value in data_frame.loc[:, 'Sale Amount']]) total_cost = sales.sum() average_cost = sales.mean() data = {'file_name': os.path.basename(input_file), 'total_sales': total_cost, 'average_sales': average_cost} all_data_frames.append(pd.DataFrame( data, columns=['file_name', 'total_sales', 'average_sales'])) data_frames_concat = pd.concat(all_data_frames, axis=0, ignore_index=True) data_frames_concat.to_csv(output_file, index = False)
XLS
使用pandas读写xls
pandas_parsing_and_write_keep_dates.py
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, sheetname='january_2013') writer = pd.ExcelWriter(output_file) data_frame.to_excel(writer, sheet_name='jan_13_output', index=False) writer.save()
过滤特定行
pandas_value_meets_condition.py
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, 'january_2013', index_col=None) data_frame_value_meets_condition = \ data_frame[data_frame['Sale Amount'].astype(float) > 1400.0] writer = pd.ExcelWriter(output_file) data_frame_value_meets_condition.to_excel( writer, sheet_name='jan_13_output', index=False) writer.save()
pandas_value_in_set.py
import string input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, 'january_2013', index_col=None) important_dates = ['01/24/2013','01/31/2013'] data_frame_value_in_set = data_frame[data_frame['Purchase Date'].isin(important_dates)] writer = pd.ExcelWriter(output_file) data_frame_value_in_set.to_excel(writer, sheet_name='jan_13_output', index=False) writer.save()
startswith , endswith , match和search等。
pandas_value_matches_pattern.py
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, 'january_2013', index_col=None) data_frame_value_matches_pattern = data_frame[ data_frame['Customer Name'].str.startswith("J")] writer = pd.ExcelWriter(output_file) data_frame_value_matches_pattern.to_excel( writer, sheet_name='jan_13_output', index=False) writer.save()
选取特定列
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, 'january_2013', index_col=None) data_frame_column_by_index = data_frame.iloc[:, [1, 4]] writer = pd.ExcelWriter(output_file) data_frame_column_by_index.to_excel( writer, sheet_name='jan_13_output', index=False) writer.save()
pandas_column_by_name.py
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, 'january_2013', index_col=None) data_frame_column_by_name = data_frame.loc[:, ['Customer ID', 'Purchase Date']] writer = pd.ExcelWriter(output_file) data_frame_column_by_name.to_excel( writer, sheet_name='jan_13_output', index=False) writer.save()
操作所有sheet
pandas_value_meets_condition_all_worksheets.py
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, sheetname=None, index_col=None) row_output = [] for worksheet_name, data in data_frame.items(): row_output.append(data[data['Sale Amount'].replace('$', ''). replace(',', '').astype(float) > 2000.0]) filtered_rows = pd.concat(row_output, axis=0, ignore_index=True) writer = pd.ExcelWriter(output_file) filtered_rows.to_excel(writer, sheet_name='sale_amount_gt2000', index=False) writer.save()
pandas_value_meets_condition_all_worksheets.py
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" data_frame = pd.read_excel(input_file, sheet_name=None, index_col=None) column_output = [] for worksheet_name, data in data_frame.items(): column_output.append(data.loc[:, ['Customer Name', 'Sale Amount']]) selected_columns = pd.concat(column_output, axis=0, ignore_index=True) writer = pd.ExcelWriter(output_file) selected_columns.to_excel( writer, sheet_name='selected_columns_all_worksheets', index=False) writer.save()
操作部分sheet
pandas_value_meets_condition_set_of_worksheets.py
import pandas as pd input_file = "sales_2013.xlsx" output_file = "pandas_output.xls" my_sheets = [0,1] threshold = 1900.0 data_frame = pd.read_excel(input_file, sheetname=my_sheets, index_col=None) row_list = [] for worksheet_name, data in data_frame.items(): row_list.append(data[data['Sale Amount'].replace('$', ''). replace(',', '').astype(float) > threshold]) filtered_rows = pd.concat(row_list, axis=0, ignore_index=True) writer = pd.ExcelWriter(output_file) filtered_rows.to_excel(writer, sheet_name='set_of_worksheets', index=False) writer.save()
处理多个excel
pandas_concat_data_from_multiple_workbooks.py
import pandas as pd import glob import os input_path = "/media/andrew/6446FA2346F9F5A0/code/foundations-for-analytics-\ with-python/excel" output_file = "pandas_output.xls" all_workbooks = glob.glob(os.path.join(input_path,'*.xls*')) data_frames = [] for workbook in all_workbooks: all_worksheets = pd.read_excel( workbook, sheet_name=None, index_col=None) for worksheet_name, data in all_worksheets.items(): data_frames.append(data) all_data_concatenated = pd.concat(data_frames, axis=0, ignore_index=True) writer = pd.ExcelWriter(output_file) all_data_concatenated.to_excel( writer, sheet_name='all_data_all_workbooks', index=False) writer.save()
pandas_sum_average_multiple_workbooks.py
import pandas as pd import glob import os input_path = "/media/andrew/6446FA2346F9F5A0/code/foundations-for-analytics-\ with-python/excel" output_file = "pandas_output.xls" all_workbooks = glob.glob(os.path.join(input_path,'*.xls*')) data_frames = [] for workbook in all_workbooks: all_worksheets = pd.read_excel(workbook, sheetname=None, index_col=None) workbook_total_sales = [] workbook_number_of_sales = [] worksheet_data_frames = [] worksheets_data_frame = None workbook_data_frame = None for worksheet_name, data in all_worksheets.items(): total_sales = pd.DataFrame( [float(str(value).strip('$').replace(',','')) for value in data.ix[:, 'Sale Amount']]).sum() number_of_sales = len(data.loc[:, 'Sale Amount']) average_sales = pd.DataFrame(total_sales / number_of_sales) workbook_total_sales.append(total_sales) workbook_number_of_sales.append(number_of_sales) data = {'workbook': os.path.basename(workbook), 'worksheet': worksheet_name, 'worksheet_total': total_sales, 'worksheet_average': average_sales} worksheet_data_frames.append( pd.DataFrame(data, columns=['workbook', 'worksheet', 'worksheet_total', 'worksheet_average'])) worksheets_data_frame = pd.concat( worksheet_data_frames, axis=0, ignore_index=True) workbook_total = pd.DataFrame(workbook_total_sales).sum() workbook_total_number_of_sales = pd.DataFrame( workbook_number_of_sales).sum() workbook_average = pd.DataFrame( workbook_total / workbook_total_number_of_sales) workbook_stats = {'workbook': os.path.basename(workbook), 'workbook_total': workbook_total, 'workbook_average': workbook_average} workbook_stats = pd.DataFrame(workbook_stats, columns=['workbook', 'workbook_total', 'workbook_average']) workbook_data_frame = pd.merge( worksheets_data_frame, workbook_stats, on='workbook', how='left') data_frames.append(workbook_data_frame) all_data_concatenated = pd.concat(data_frames, axis=0, ignore_index=True) writer = pd.ExcelWriter(output_file) all_data_concatenated.to_excel( writer, sheet_name='sums_and_averages', index=False) writer.save()
使用excel绘制图表
import pandas as pd import random # Some sample data to plot. cat_1 = ['y1', 'y2', 'y3', 'y4'] index_1 = range(0, 21, 1) multi_iter1 = {'index': index_1} for cat in cat_1: multi_iter1[cat] = [random.randint(10, 100) for x in index_1] # Create a Pandas dataframe from the data. index_2 = multi_iter1.pop('index') df = pd.DataFrame(multi_iter1, index=index_2) df = df.reindex(columns=sorted(df.columns)) # Create a Pandas Excel writer using XlsxWriter as the engine. excel_file = 'legend.xlsx' sheet_name = 'Sheet1' writer = pd.ExcelWriter(excel_file, engine='xlsxwriter') df.to_excel(writer, sheet_name=sheet_name) # Access the XlsxWriter workbook and worksheet objects from the dataframe. workbook = writer.book worksheet = writer.sheets[sheet_name] # Create a chart object. chart = workbook.add_chart({'type': 'line'}) # Configure the series of the chart from the dataframe data. for i in range(len(cat_1)): col = i + 1 chart.add_series({ 'name': ['Sheet1', 0, col], 'categories': ['Sheet1', 1, 0, 21, 0], 'values': ['Sheet1', 1, col, 21, col], }) # Configure the chart axes. chart.set_x_axis({'name': 'Index'}) chart.set_y_axis({'name': 'Value', 'major_gridlines': {'visible': False}}) # Insert the chart into the worksheet. worksheet.insert_chart('G2', chart) # Close the Pandas Excel writer and output the Excel file. writer.save()

参考资料:http://pandas-xlsxwriter-charts.readthedocs.io/