[R] R-package TDA- RipsDiag issues

[lstat]

Hi there, 
I was hoping you could help me out with the following:
- I am trying to compute the diagram of a Rips filtration built on top of a
point cloud. 
I've gone through several tutorials, and I always get the same answer as the
tutorial. Let's say I am inputting an n by d matrix of coordinates, where n
is the number of points in d dimensional space, I am able to get a
persistence diagram with dimensions 0, 1, and 2-- when I specify
maxdimension=2. 
HOWEVER-- I was wondering; if you input an N BY N matrix of distances of n
points, say a 15 by 15 matrix, which is what I am working with, I can't ever
see any 2 dimensional features, or 1 dimensional-- the diagram always shows
dim0, no matter what matrix I input. 
The code I have been using is as follows: 
Diag<-ripsDiag(XX, maxscale, dist="arbitrary", printProgress=TRUE), where XX
is the name of my distance matrix. 
Is it not possible to ever extract dim 1 or dim 2 features from this? Even
though I specified maxdimension=2. 
Could someone please help me out, as this is causing great grief. 
In the tutorial I found online by cran project, they input a distance matrix
for a triangle with lengths 1,2, and 4; they specify maxdimension=1,
maxscale=5, and input the same as I did above; they only get dim0 features
on the diagram... wouldn't we expect the loop of the triangle to be a key
feature?
If not, either way, would we not expect to see dim1 and dim2 noise features
at all?

Thanks so much!



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