Added export functionality to pivotUI

[ashesnz]

Hello Nicolas,

Thought I might contribute to this fantastic library of yours. Added an optional field to pivoutUI in which the user can export the table.

I had to normalize the table before being able to do this, as it got quite difficult due to the rowspan/colspans involved.

Feel free to merge, if you so desired

[jawaharprasad]

Works well but it repeats the first dimension column twice.. in your PR, it repeats the COLOR column in both A,B Columns in excel

[nicolaskruchten]

Thanks for this! I'm getting married soon so I won't have a ton of time to look at this until September, but I just wanted to let you know I'm grateful and I'm not ignoring you :)

[nicolaskruchten]

Thanks again for the contribution, but commit f636484 is my preferred way of implementing exporting: via an optional Renderer component which directly accesses the underlying PivotData object rather than by patching the core and parsing the output of another Renderer.

[LaurensRietveld]

@nicolaskruchten : not really sure this is the best place for the bug report, but I noticed two strange issues:

• The totals column disappears in this example: http://nicolas.kruchten.com/pivottable/examples/mps_export.html
• when adding another row variable, the column headers are concatenated. Is this intentional?

[nicolaskruchten]

@LaurensRietveld thanks for the feedback!

• I should probably add the totals columns back in, you're right that it's inconsistent
• yes, it's intentional as it simplifies importing into many tools which expect a single row of headers... having multiple rows of headers makes things complicated in a layout like TSV which doesn't have intuitive support for multi-row/multi-column cells. I tried various options that didn't do this but I always ended up with either a blank row or a blank column in the layout and it wasn't very satisfying

I'm very open to suggestions as to alternative ways of doing this, though!

[LaurensRietveld]

Sorry about the delay!

I think there is no -proper- way of doing this, and what table layout to use mostly depends on a persons taste. I have two main requirements:

1. it should resemble the regular table layout as much as possible
2. the csv should support the use in easily applying postprocessing in e.g. excel

So for (1) I'd opt for including the row-headers instead of concatenating these with the cell values. And for (2), I'd simply duplicate a row span value into the corresponding cells.

But again, this is just my personal preference, and I'm not claiming this to be -the- best approach ;)
It's not the prettiest solution, but I doubt there is any...

ps. Something more related to the UI part of this issue: if you share my preference for requirement (1), then it might be better to make this agnostic to the underlying data object, and generate the exported csv on the actual html table. This would make it easier to keep the CSV as consistent as possible with the regular table renderer(s).