skbio.stats.distance.randdm(num_objects, ids=None, constructor=None, random_fn=None)[source]#

Generate a distance matrix populated with random distances.

Using the default random_fn, distances are randomly drawn from a uniform distribution over [0, 1).

Regardless of random_fn, the resulting distance matrix is guaranteed to be symmetric and hollow.


The number of objects in the resulting distance matrix. For example, if num_objects is 3, a 3x3 distance matrix will be returned.

idssequence of str or None, optional

A sequence of strings to be used as IDs. len(ids) must be equal to num_objects. If not provided, IDs will be monotonically-increasing integers cast as strings (numbering starts at 1). For example, ('1', '2', '3').

constructortype, optional

DissimilarityMatrix or subclass constructor to use when creating the random distance matrix. The returned distance matrix will be of this type. If None (the default), a DistanceMatrix instance will be returned.

random_fnfunction, optional

Function to generate random values. random_fn must accept two arguments (number of rows and number of columns) and return a 2D numpy.ndarray of floats (or something that can be cast to float). If None (the default), numpy.random.rand will be used.


DissimilarityMatrix (or subclass) instance of random distances. Type depends on constructor.