# How to replace markups with np.array in application MarkupsToModel
**URL:** https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000
**Category:** Development
**Tags:** python
**Created:** [August 30, 2022, 1:20pm UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000 "2022-08-30T13:20:02Z")
**Posts on this page:** 12
**Page:** 1
### Author:  [@jumbojing](https://discourse.slicer.org/u/jumbojing)
#### Post date: [August 30, 2022, 1:20pm UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/1 "2022-08-30T13:20:02Z")
I want to convert a set of point clouds (np.array) to closed surfaces, How to use `np.array` directly in `MarkupsToModel` instead of converting `np.array` to `Markups`?
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### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [August 30, 2022, 6:49pm UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/2 "2022-08-30T18:49:24Z")
You need to convert the numpy array to a MRML model node to use it in Slicer modules. Bulk data (point coordinates) does not have to be copied, so the conversion should take negligible time.
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### Author:  [@jumbojing](https://discourse.slicer.org/u/jumbojing)
#### Post date: [August 30, 2022, 10:25pm UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/3 "2022-08-30T22:25:05Z")
Thanks!!!@lassosan
I see 😇
> [@lassoan](#):
>
> convert the numpy array to a MRML model node
但是, 我想要这个👇面积, 可是转化为model后得到的表面积似乎有点大, 转化为curve后得到的面积似乎又太小了…
> However, I want 👇 this area, but the surface area obtained after converting to model seems to be too large, and the area obtained after converting to curve seems to be too small…what’s wrong?
>
> 
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### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [August 31, 2022, 12:47am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/4 "2022-08-31T00:47:53Z")
What is your end goal?
What the point cloud represents (points on a curve, points on surface, points in a 3D region,…)?
Do you need to interact with the points or just create a model?
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### Author:  [@jumbojing](https://discourse.slicer.org/u/jumbojing)
#### Post date: [August 31, 2022, 12:53am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/5 "2022-08-31T00:53:55Z")
I want to get the area of contours formed by a set of point clouds (np.array) that lie in a plane.
👇
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### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [August 31, 2022, 2:48am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/6 "2022-08-31T02:48:01Z")
Do you want to fit a plane to these points? You can do that directly using a markup plane, as shown [here](https://slicer.readthedocs.io/en/latest/developer_guide/script_repository.html#fit-markups-plane-to-model). Note that points are imported into a model node instead of a markup point list node.
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### Author:  [@jumbojing](https://discourse.slicer.org/u/jumbojing)
#### Post date: [August 31, 2022, 3:12am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/7 "2022-08-31T03:12:43Z")
No…I want the surface Area of contours formed by a set of point clouds (np.array) …
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### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [August 31, 2022, 3:20am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/8 "2022-08-31T03:20:48Z")
If you want to compute soap bubble surface from ordered points along a closed curve then you can do that by importing the points into a markup closed curve node and enabling the “area” measurement. If you want to see the generated surface then I would recommend to use the [Baffle Planner module in SlicerHeart extension](https://github.com/SlicerHeart/SlicerHeart/blob/master/Docs/BafflePlanner.md) and then get the surface area of the generated model from the Models module.
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### Author:  [@jumbojing](https://discourse.slicer.org/u/jumbojing)
#### Post date: [August 31, 2022, 11:52pm UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/9 "2022-08-31T23:52:40Z")
I tried to compute the [quote=“lassoan, post:8, topic:25000”]
surface from ordered points along a closed curve then you can do that by importing the points into a markup closed curve node
[/quote], but found that its efficiency is too low, especially when using `slicer.util.updateMarkupsControlPointsFromArray`, is there a better and faster method to get a curve from np.array?
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### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [September 3, 2022, 2:05am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/10 "2022-09-03T02:05:45Z")
I’ve fixed the performance issue in the latest Slicer Preview Release (that you download 2022-09-03 or later). Now `slicer.util.updateMarkupsControlPointsFromArray` should complete immediately.
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### Author:  [@jumbojing](https://discourse.slicer.org/u/jumbojing)
#### Post date: [September 3, 2022, 2:43am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/11 "2022-09-03T02:43:33Z")
> [@lassoan](#):
>
> in the latest Slicer Preview Release (that you download 2022-09-03 or later)
Can I only replace the util.py file in the my current version (5.1.0-2022-05-08) Slicer with [util.py](https://github.com/Slicer/Slicer/blob/main/Base/Python/slicer/util.py) without updating the Slicer?
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### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [September 3, 2022, 3:21am UTC](https://discourse.slicer.org/t/how-to-replace-markups-with-np-array-in-application-markupstomodel/25000/12 "2022-09-03T03:21:47Z")
As I remember I’ve made some more improvements since Slicer-5.0.3 in C++ code, so updating util.py is probably not sufficient. Another complication may be that util.py of Slicer-5.1 may not be compatible with Slicer-5.0. I would recommend to download the Slicer Preview Release tomorrow and use that.