如何使用python使用Excel绘制图表？

Question

Hi I intend to draw a chart with data in an xlsx file. In order to keep the style, I HAVE TO draw it within excel. I found a package named win32com, which can give a support to manipulate excel file with python on win32 platform, but I don't know where is the doc.....

Another similar question is how to change the style of cells, such as font, back-color ? So maybe all I wanna know is the doc, you know how to fish is more useful than fishes.... and an example is better.

Answer 1

Check this lib, almost native excel graph can be generated here.

xlsxwriter line chart example

The only catch here is that you can't update the already existing sheet, means you can modify the sheet, with this lib you can create all most all the charts.

Answer 2

Documentation for win32com is next to non-existent as far I know. However, I use the following method to understand the commands.

1. MS-Excel

   In Excel, record a macro of whatever action you intend to, say plotting a chart. Then go to the Macro menu and use View Macro to get the underlying commands. More often than not, the commands used would guide you to the corresponding commands in python that you need to use.

2. Pythonwin

   You can use pythonwin to browse the underlying win32com defined objects (in your case Microsoft Excel Objects). In pythonwin (which can be found at \\Lib\\site-packages\\pythonwin\\ in your python installation), go to Tools -> COM Makepy Utility, select your required Library (in this case, Microsoft Excel 14.0 Object Library) and press Ok. Then when the process is complete, go to Tools -> COM Browser and open the required library under Registered Libraries. Note the ID no. as this would correspond to the source file. You can browse the various components of the library in the COM Browser.

3. Source

   Go to \\Lib\\site-packages\\win32com\\ in your python installation folder. Run makepy.py and choose the required library. After this, the source file of the library can be found at \\Lib\\site-packages\\win32com\\gen_py . It is one of those files with the wacky name. The name corresponds to that found in Pythonwin. Open the file, and search for the commands you saw in the Excel Macro. (#2 and #3 maybe redundant, I am not sure)

Answer 3

AFAIK, win32com is an interface to Microsoft's COM technology , so you'd have to look there for an explanation of what objects and methods are available for the different COM-enabled applications. Your task will probably be easier if you don't start with an empty spreadsheet and try to create everything using win32com from scratch, but to create a template in Excel which only needs the actual data filled in. Actualy, since Excel can use ODBC data sources, maybe a database is an even better interface?

Answer 4

import win32com.client as w32

oe = w32.Dispatch("Excel.Application")
ow = oe.Workbooks.Add()
osh = ow.Sheets(1)
osh.Select()
osh.Activate()
osh.Cells(1,1).Font.Bold = True # set A1 to bold
osh.Range("A1").Interior.Color = RGB(255,0,0) # set to red background color