unit of measure (density;gradient)

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Luca1988SCENE
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Joined: Fri May 23, 2014 10:17 am

Re: unit of measure (density;gradient)

Post by Luca1988SCENE »

hi daniel, honestly i didn't understand so much your speech, when you say "or more generally that its values can't change faster than the distance between points" what are you going to explain ? i have a cloud wich is derived from a registration from 4 clouds picked up by laserscanning. i have about 5 milion points in few m^2....have i to click yes or now when CC ask me if the scalar field is composed by euclidian dist ?
Thanks
daniel
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Re: unit of measure (density;gradient)

Post by daniel »

The most important part was "rarely in practice!": always click "no" by default...
Daniel, CloudCompare admin
Luca1988SCENE
Posts: 31
Joined: Fri May 23, 2014 10:17 am

Re: unit of measure (density;gradient)

Post by Luca1988SCENE »

Hi Daniel, i 'm writing my thesis but i still have few questions for you ;)...
- which unit of measure has the gradient ( degrees?)?
- why the "gauss: mean" value is equal to 0.0000? when CC compute the distance between a fit plane and its cloud returns me a Gauss distribution but it don't specify me the mean Gauss value

Thanks a lot
Luca1988SCENE
Posts: 31
Joined: Fri May 23, 2014 10:17 am

Re: unit of measure (density;gradient)

Post by Luca1988SCENE »

here one photo for Gauss: mean value
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daniel
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Re: unit of measure (density;gradient)

Post by daniel »

- the gradient is expressed in 'units of the scalar field' / 'units of distance' (because we compute something equivalent to a difference of scalar values divided by a distance between points)
- when we fit a plane on a point cloud we compute the "mean squares" solution. This solution is such that the mean distance of the points to this plane is 0 by definition.
- you can ask for the Gaussian distribution of a scalar field any time by selecting the cloud that hosts the scalar field and then calling the "Edit > Scalar fields > Compute stat. params" method (then simply select the "Gauss" distribution). The scalar field must be the active/visible one.

You should also display the Console (F8). Interesting information is displayed in it from time to time (such as the distribution parameters, etc.).
Daniel, CloudCompare admin
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