export - Exporting SmoothHistogram plot data

My program produces a large data set, which is distributed by some unknown function. I've used SmoothHistogram to visualise it crudely as a probability distribution function, but now I want to export the plot data from SmoothHistogram - is there a way for me to retrieve just the line SmoothHistogram plots, so I can analyse it in an external program?

Answer

There are two methods:

Extract the data directly from the SmoothHistogram plot:

r = RandomReal[NormalDistribution[], 1000];
plot = SmoothHistogram[r]

enter image description here

pts1 = Join @@ Cases[plot, Line[p__] :> p, ∞]

{{-4.10173, 0.}, {-4.10173, 0.}, {-4.09273, 0.000372864}, ... }

Use regular HistogramList with the subsequent smoothing
```
pts2 = Transpose@{(Most[#] + Rest[#])/2, 
  GaussianFilter[#2, 12 {3, 1}, Padding -> 0.0]} & @@ 

    HistogramList[r, {-3.5, 3.5, 0.02}, "PDF"];
```
Here 12*3 = 36 is the radius of Gaussian smoothing and 12*1 = 12 is the standard deviation in units 0.02.

Verification:

ListLinePlot[{pts1, pts2}]

enter image description here

Then you can Export pts1 or pts2.

Comments

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