scipy tutorial - Baustatik-Info-Server

SciPy Reference Guide, Release 0.8.dev
is_valid_im(R, warning=False, throw=False, name=None)
Returns True if the inconsistency matrix passed is valid. It must be a n by 4 numpy array of doubles. The
standard deviations R[:,1] must be nonnegative. The link counts R[:,2] must be positive and no greater
than n − 1.
Arguments
Returns
• R : ndarray The inconsistency matrix to check for validity.
• warning : bool When True, issues a Python warning if the linkage matrix passed is
invalid.
• throw : bool When True, throws a Python exception if the linkage matrix passed is
invalid.
• name : string This string refers to the variable name of the invalid linkage matrix.
• b : bool True iff the inconsistency matrix is valid.
is_valid_linkage(Z, warning=False, throw=False, name=None)
Checks the validity of a linkage matrix. A linkage matrix is valid if it is a two dimensional nd-array (type
double) with n rows and 4 columns. The first two columns must contain indices between 0 and 2n − 1. For a
given row i, 0 ≤ Z[i, 0] ≤ i + n − 1 and 0 ≤ Z[i, 1] ≤ i + n − 1 (i.e. a cluster cannot join another cluster
unless the cluster being joined has been generated.)
Arguments
Returns
• warning : bool When True, issues a Python warning if the linkage matrix passed is
invalid.
• throw : bool When True, throws a Python exception if the linkage matrix passed is
invalid.
• name : string This string refers to the variable name of the invalid linkage matrix.
• b
leaders(Z, T)
(L, M) = leaders(Z, T):
[bool] True iff the inconsistency matrix is valid.
Returns the root nodes in a hierarchical clustering corresponding to a cut defined by a flat cluster assignment
vector T. See the fcluster function for more information on the format of T.
For each flat cluster j of the k flat clusters represented in the n-sized flat cluster assignment vector T, this
function finds the lowest cluster node i in the linkage tree Z such that:
•leaf descendents belong only to flat cluster j (i.e. T[p]==j for all p in S(i) where S(i) is the set of leaf
ids of leaf nodes descendent with cluster node i)
•there does not exist a leaf that is not descendent with i that also belongs to cluster j (i.e. T[q]!=j for
all q not in S(i)). If this condition is violated, T is not a valid cluster assignment vector, and an exception
will be thrown.
140 Chapter 3. Reference