Fit the cumulative percentage line to the sorted histogram output

[David Luu]

This is what I have so far: https://gist.github.com/daluu/fc1cbcab68852ed3c5fa and http://bl.ocks.org/daluu/fc1cbcab68852ed3c5fa. I'm trying to replicate Excel functionality.

The line fits the default histogram just fine as in the base/original http://bl.ocks.org/daluu/f58884c24ff893186416. And I'm able to sort the histogram in descending frequency, although in doing so, I switched x scales (from linear to ordinal). I can't seem to map the line to the sorted histogram correctly at this point.

What's the best design approach to get the remaining part working? Should I have started with a single x scale and not need to switch from linear to ordinal? If so, I'm not sure how to apply the histogram layout correctly using an ordinal scale or how not to use a linear x scale as a source of input to the histogram layout and still get the desired output.

Using the same ordinal scale with the code I have so far, the line looks ok but it's not the curve I am expecting to see. As for what the final output should look like, a comment in the gist has a screenshot of the Excel reference chart.

Any help appreciated.