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gdkrmr / dimRed

A Framework for Dimensionality Reduction in R
https://www.guido-kraemer.com/software/dimred/
GNU General Public License v3.0
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LandMark ISOMAP #21

Closed yancychy closed 2 years ago

yancychy commented 6 years ago

Hi, the ISOMAP function run fast. But Is there any method to automatically select landmark points in your ISOMAP? Many thanks.

gdkrmr commented 6 years ago

no, there is not. If you give me a reference I may implement this in the future. I did not know about Rdimtools, seems like they put a lot of effort in it. The Isomap in current master is even faster than the one currently on CRAN.

gdkrmr commented 6 years ago

In order for Isomap to work nicely, the underlying manifold needs to be "unfoldable" to 2d or 3d euclidean space, if this is not given, Isomap will not produce usable output.

The running time for t-SNE and pca seems a little bit high, t-SNE should be able to embed 70000 points in under 30 minutes.