# How to acquire the histogram statistic data from the vtkPolyData?

**URL:** https://discourse.vtk.org/t/how-to-acquire-the-histogram-statistic-data-from-the-vtkpolydata/1203
**Category:** Support
**Created:** [June 24, 2019, 9:09am UTC](https://discourse.vtk.org/t/how-to-acquire-the-histogram-statistic-data-from-the-vtkpolydata/1203 "2019-06-24T09:09:27Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Kim\_William](https://discourse.vtk.org/user_avatar/discourse.vtk.org/kim_william/32/373_2.png) [@Kim\_William](https://discourse.vtk.org/u/Kim_William)
#### Post date: [June 24, 2019, 9:09am UTC](https://discourse.vtk.org/t/how-to-acquire-the-histogram-statistic-data-from-the-vtkpolydata/1203/1 "2019-06-24T09:09:27Z")

</div>

Hi all 🙂

I want to acquire the histogram statistics data from a specific row, after loading the 3D model file.  
(ex, Max / Min / Average / Std)

In OpenCV, it can acquire the data using the as below code:

```
cv::Mat image(rows, cols, CV_8U);
cv::Mat line = image.row(num); // a specific row
cv::Scalar mean, dev;
cv::meanStdDev(line, mean, dev);

```

Similar to the above example, can I acquire the histogram statistics data from a specific row of vtkPolyData?

Actually, my purpose is showing the plot chart on specific row data of vtkPolyData.

Please, give me advise.

Thank you 🙂