How can using randomly delete method?

StanleyTas

This is my process.

and this is my result



but, this result is error.

I need to show this one↓



who can tell me, I lost what's attribute?

this is csv file.

MartinLiebig

Hi @StanleyTas ,

I am sorry, but from your description it is unclear what your problem is?

Best,

Martin

StanleyTas

I mean, how can use csv file to display the result.

Task: Randomly delete 70% of the points of the outer spiral (see figures below).

I had tried more methods, but I always fail

Telcontar120

I think you probably need to define two clusters using a method like DBSCAN, which will isolate the two spirals from each other.  Once you have that, then you can generate a random number for the first cluster (or the one that corresponds to the outer spiral) and then remove 70% of those based on a simple numerical threshold.

StanleyTas

I have to use DBSCAN operation, but I don't know why cannot succeed.

StanleyTas

who knows how can solve it?

MartinLiebig

Hi,

what you probably want to do: Apply DBScan on your data, check for the cluster which makes the outer ring, Filter for the outer ring, sample it down.

This should be enough to solve this. We are happy to help here with questions to our software. We are however not doing your complete assignments.

Best,

Martin

StanleyTas

that's no assignment, it just exercise

MartinLiebig

Than I am sorry, pretty much looks like an assignment from a university.