skfolio.cluster.LinkageMethod

class skfolio.cluster.LinkageMethod(*values)

Methods for calculating the distance between clusters in the linkage matrix. See the Linkage Methods section of scipy.cluster.hierarchy.linkage for full descriptions.

Parameters:

SINGLEstr

Assigns

\[d(u,v) = \min(dist(u[i],v[j]))\]

for all points \(i\) in cluster \(u\) and \(j\) in cluster \(v\). This is also known as the Nearest Point Algorithm.

COMPLETEstr

Assigns

\[d(u, v) = \max(dist(u[i],v[j]))\]

for all points \(i\) in cluster u and \(j\) in cluster \(v\). This is also known by the Farthest Point Algorithm or Voor Hees Algorithm.

AVERAGEstr

Assigns

\[d(u,v) = \sum_{ij} \frac{d(u[i], v[j])}{(|u|*|v|)}\]

for all points \(i\) and \(j\) where \(|u|\) and \(|v|\) are the cardinalities of clusters \(u\) and \(v\), respectively. This is also called the UPGMA algorithm.

WEIGHTEDstr

Assigns

\[d(u,v) = (dist(s,v) + dist(t,v))/2\]

where cluster u was formed with cluster s and t and v is a remaining cluster in the forest (also called WPGMA).

CENTROIDstr

Assigns

\[dist(s,t) = ||c_s-c_t||_2\]

where \(c_s\) and \(c_t\) are the centroids of clusters \(s\) and \(t\), respectively. This is also known as the UPGMC algorithm.

MEDIANstr

assigns :math:`d(s,t)` like the ``centroid`` method.

This is also known as the WPGMC algorithm.

WARDstr

Uses the Ward variance minimization algorithm. The new entry \(d(u,v)\) is computed as follows,

\[d(u,v) = \sqrt{\frac{|v|+|s|} {T}d(v,s)^2 + \frac{|v|+|t|} {T}d(v,t)^2 - \frac{|v|} {T}d(s,t)^2}\]

where \(u\) is the newly joined cluster consisting of clusters \(s\) and \(t\), \(v\) is an unused cluster in the forest, \(T=|v|+|s|+|t|\), and \(|*|\) is the cardinality of its argument. This is also known as the incremental algorithm.

Methods

capitalize(/)	Return a capitalized version of the string.
casefold(/)	Return a version of the string suitable for caseless comparisons.
center(width[, fillchar])	Return a centered string of length width.
count
encode(/[, encoding, errors])	Encode the string using the codec registered for encoding.
endswith
expandtabs(/[, tabsize])	Return a copy where all tab characters are expanded using spaces.
find
format(*args, **kwargs)	Return a formatted version of the string, using substitutions from args and kwargs.
format_map(mapping, /)	Return a formatted version of the string, using substitutions from mapping.
index
isalnum(/)	Return True if the string is an alpha-numeric string, False otherwise.
isalpha(/)	Return True if the string is an alphabetic string, False otherwise.
isascii(/)	Return True if all characters in the string are ASCII, False otherwise.
isdecimal(/)	Return True if the string is a decimal string, False otherwise.
isdigit(/)	Return True if the string is a digit string, False otherwise.
isidentifier(/)	Return True if the string is a valid Python identifier, False otherwise.
islower(/)	Return True if the string is a lowercase string, False otherwise.
isnumeric(/)	Return True if the string is a numeric string, False otherwise.
isprintable(/)	Return True if all characters in the string are printable, False otherwise.
isspace(/)	Return True if the string is a whitespace string, False otherwise.
istitle(/)	Return True if the string is a title-cased string, False otherwise.
isupper(/)	Return True if the string is an uppercase string, False otherwise.
join(iterable, /)	Concatenate any number of strings.
ljust(width[, fillchar])	Return a left-justified string of length width.
lower(/)	Return a copy of the string converted to lowercase.
lstrip([chars])	Return a copy of the string with leading whitespace removed.
maketrans
partition(sep, /)	Partition the string into three parts using the given separator.
removeprefix(prefix, /)	Return a str with the given prefix string removed if present.
removesuffix(suffix, /)	Return a str with the given suffix string removed if present.
replace(old, new, /[, count])	Return a copy with all occurrences of substring old replaced by new.
rfind
rindex
rjust(width[, fillchar])	Return a right-justified string of length width.
rpartition(sep, /)	Partition the string into three parts using the given separator.
rsplit(/[, sep, maxsplit])	Return a list of the substrings in the string, using sep as the separator string.
rstrip([chars])	Return a copy of the string with trailing whitespace removed.
split(/[, sep, maxsplit])	Return a list of the substrings in the string, using sep as the separator string.
splitlines(/[, keepends])	Return a list of the lines in the string, breaking at line boundaries.
startswith
strip([chars])	Return a copy of the string with leading and trailing whitespace removed.
swapcase(/)	Convert uppercase characters to lowercase and lowercase characters to uppercase.
title(/)	Return a version of the string where each word is titlecased.
translate(table, /)	Replace each character in the string using the given translation table.
upper(/)	Return a copy of the string converted to uppercase.
zfill(width, /)	Pad a numeric string with zeros on the left, to fill a field of the given width.

classmethod has(value)

Check if a value is in the Enum.

Parameters:

valuestr

Input value.

Returns:

xbool

True if the value is in the Enum, False otherwise.