replace_data fails and give the KeyError: 'rId3'

[jiaguoshida]

File "D:/pythonScripts/pythonPPT/***.py", line 49, in
chart.replace_data(chart_data)
File "C:\ProgramData\Anaconda3\lib\site-packages\pptx\chart\chart.py", line 178, in replace_data
self._workbook.update_from_xlsx_blob(chart_data.xlsx_blob)
File "C:\ProgramData\Anaconda3\lib\site-packages\pptx\parts\chart.py", line 69, in update_from_xlsx_blob
xlsx_part = self.xlsx_part
File "C:\ProgramData\Anaconda3\lib\site-packages\pptx\parts\chart.py", line 85, in xlsx_part
return self._chart_part.related_parts[xlsx_part_rId]
KeyError: 'rId3'

[ssanthosh243]

Even i received the same error, Please let me if there is error in the implemented code.

[scanny]

I would look to the provenance of the PPTX file. This would indicate that a relationship to the Excel data behind the chart is not present in the slide .rels file. If you copied the slide or otherwise manipulated the PPTX file that could explain it. In any case, it represents a corruption of the file.

I believe if you try the same operation on a freshly created PPTX you will not receive this error.

[xmuxiaokun]

File "D:/pythonScripts/pythonPPT/***.py", line 49, in
chart.replace_data(chart_data)
File "C:\ProgramData\Anaconda3\lib\site-packages\pptx\chart\chart.py", line 178, in replace_data
self._workbook.update_from_xlsx_blob(chart_data.xlsx_blob)
File "C:\ProgramData\Anaconda3\lib\site-packages\pptx\parts\chart.py", line 69, in update_from_xlsx_blob
xlsx_part = self.xlsx_part
File "C:\ProgramData\Anaconda3\lib\site-packages\pptx\parts\chart.py", line 85, in xlsx_part
return self._chart_part.related_parts[xlsx_part_rId]
KeyError: 'rId3'

I also met this problem, and I found that if I paste the chart to a pptx from a '.xls' Excel workbook, then the same error will raise, but that won't happen if I use a '.xlsx‘ Excel workbook.
I'm not sure whether it's because '.xls' and '.xlsx' use different file structures, since '.xlsx' use XML but '.xls' not.
Note that when pasting the chart to your powerpoint, you have to choose the option 'Keep Source Formatting'.

[scanny]

Ah, very useful observation @xmuxiaokun! It definitely makes sense that this would be related to charts from pre-Excel 2007 files.

[ParmendraPBI]

Is there any way so that I can directly copy data from excel to chart data sheet?

[zhar97]

Mentioned by @scanny
... This would indicate that a relationship to the Excel data behind the chart is not present in the slide .rels file...

This idea has led me to diagnose the relationship between the data and the chart -- yes, indeed, (in my case) the dataset (external .xlsx) got disconnected from the chart.

I've come to believe that external data source may be one of the source of error rId3; after testing the following scenario:

1. Create a .pptx template with chart connected to external dataset.xlsx.
2. Create a .pptx template with chart using dataset keyed-in internally.
Both were then transferred to another PC along with python-pptx_program.py but without dataset.xlsx.

Turned out, the program run on 2 just fine but encounter rId3 again for 1.

So, my workaround was simply to initialise dummy chart (with dummy data) per required design and run chart.replace_data(...) as it meant to be. Little tweak using python-pptx to make sure everything as I intended it to be and voila - Data Replacement is done.

=======================
If this is the only cause to the error, then the problem does not underlie in python-pptx module but the XML build on the PPTX itself and how the PowerPoint works to ensure data integrity.