# -*- coding: utf-8 -*-
from itertools import combinations
from pandas import DataFrame, concat
from plotnine import ggplot, aes, geom_point, geom_text, geom_segment, scale_color_manual, arrow
#interns functions
from .utils import check_is_valid_axis, check_is_valid_geom
from .fviz import set_axis, list_colors
[docs]
def fviz_dist(
obj,
axis = [0,1],
geom = ("point","text"),
repel = False,
point_args = dict(shape = "^", size = 3),
text_args = dict(size = 11.5),
palette = None,
x_lim = None,
y_lim = None,
x_label = None,
y_label = None,
title = None,
add_hline = True,
add_vline = True,
add_grid = True,
ggtheme = None
):
"""
Visualize distance between barycenter
Parameters
----------
obj : class
An instance of class :class:`~discrimintools.CANDISC`, :class:`~discrimintools.DiCA`, :class:`~discrimintools.CPLS`, :class:`~discrimintools.PLSDA`, :class:`~discrimintools.PLSLDA`, :class:`~discrimintools.PLSLOGIT`.
axis : list, defaul=[0,1]
Dimensions to be plotted
geom : str, list or tuple, default = ('point','text')
Geometry to be used for the graph. Possible values are the combinaison of ["point","text"].
- 'point' to show only points,
- 'text' to show only labels,
- ('point','text') to show both types.
repel : bool, default = False
To avoid overplotting text labels.
point_args : dict, default = dict(shape = "o", size = 1.5)
Keywords arguments for `geom_point <https://plotnine.org/reference/geom_point.html>`_.
text_args : dict, default = dict(size = 8)
Keywords arguments for `geom_text <https://plotnine.org/reference/geom_text.html>`_.
palette : None or list, default = None
Color palette to be used for coloring by groups.
x_lim : None, list or tuple, default = None
The range of the plotted ``x`` values
y_lim : None, list or tuple, default = None
The range of the plotted ``y`` values
x_label : None or str, default = None
The label text of ``x``.
y_label : None or str, default = None
The label text of ``y``.
title : None or str, default = None
The title of the graph you draw.
add_hline : bool, default = True
To add a horizontal line.
add_vline : bool, default = True
To add a vertical line.
add_grid : bool, default = True
To add grid customization.
ggtheme : function, default = None
Plotnine `theme <https://plotnine.org/guide/themes-premade.html>`_ name.
Returns
-------
p : class
A object of class ggplot.
Examples
--------
>>> from discrimintools.datasets import load_wine
>>> from discrimintools import CANDISC, fviz_dist
>>> D = load_wine() # load training dataset
>>> y, X = D["Quality"], D.drop(columns=["Quality"]) # split into X and y
>>> clf = CANDISC()
>>> clf.fit(XTrain,yTrain)
CANDISC()
>>> p = fviz_dist(clf) # graph of distance between barycenter
>>> print(p)
.. figure:: ../../../../_static/fviz_candisc_dist.png
Distance between barycenter - CANDISC
"""
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#check if obj is an instance of class CANDISC or DiCA
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
if obj.model_ not in ["candisc","dica","cpls", "plsda","plslda","plslogit"]:
raise TypeError("'obj' must be an instance of class CANDISC, DiCA, CPLS, PLSDA, PLSLDA, PLSLOGIT")
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#check if valid iaxis
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
check_is_valid_axis(obj,axis)
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#check if valid geom
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
check_is_valid_geom(geom,('point','text'))
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#set text arguments - add overlap arguments
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
if repel and "text" in geom:
text_args = dict(**text_args,adjust_text=dict(arrowprops=dict(arrowstyle='-',lw=1.0)))
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#set index and palette
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#set index
index = obj.call_.classes
#set palette
if palette is None:
palette = list_colors[:len(index)]
elif not isinstance(palette,(list,tuple)):
raise TypeError("'palette' must be a list or a tuple of colors")
elif len(palette) != len(index):
raise TypeError(f"'palette' must be a list or tuple with length {len(index)}.")
#classes coordinates
coord = obj.classes_.coord
coord[f"{obj.call_.target}"] = list(coord.index)
#set x_text and y_text
x_text, y_text = "Can"+str(axis[0]+1), "Can"+str(axis[1]+1)
if obj.model_ == "candisc":
#square mahalanobis distance
dist2 = obj.classes_.mahal
else:
#squared euclidean distance
dist2 = obj.classes_.eucl
#all combinations of two classes
all_comb = combinations(coord.index,r=2)
data = DataFrame()
i = 0
for comb in all_comb:
From, To = comb[0], comb[1]
dist = round(dist2.loc[From,To],2)
x, y = coord.loc[From,x_text], coord.loc[From,y_text]
xend, yend = coord.loc[To,x_text], coord.loc[To,y_text]
xmid, ymid = 0.5*(x + xend), 0.5*(y + yend)
row = DataFrame(dict(x=x,y=y,xend=xend,yend=yend,xmid=xmid,ymid=ymid,dist=dist),index=[i])
data = concat((data,row),axis=0)
i +=1
#initialize
p = ggplot()
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#add classes coordinates
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
if "point" in geom:
p = p + geom_point(data=coord,mapping=aes(x=x_text,y=y_text,color=obj.call_.target,label=coord.index),**point_args)
if "text" in geom:
p = p + geom_text(data=coord,mapping=aes(x=x_text,y=y_text,color=obj.call_.target,label=coord.index),**text_args)
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#add color scale
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
p = p + scale_color_manual(values=palette,labels=index)
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#add distance
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
p = p + geom_segment(data=data,mapping=aes(x="x",y="y",xend="xend",yend="yend"),color="black",linetype="dashed",size=0.5,
arrow = arrow(angle=30,length=0.2/2.54,ends="both",type="open"))
#add labels
p = p + geom_text(data=data,mapping=aes(x="xmid",y="ymid",label="dist"),color="blue",size=10)
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#add others elements
#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
if obj.model_ in ["candisc","dica"]:
prop = obj.eig_.iloc[:,2]
else:
prop = obj.explained_variance_.iloc[:,0]
#set x label
if x_label is None:
x_label = "Can{} ({}%)".format(axis[0]+1,round(prop[axis[0]],1))
#set y label
if y_label is None:
y_label = "Can{} ({}%)".format(axis[1]+1,round(prop[axis[1]],1))
#set title
if title is None:
title = "Distance between barycenter - {}".format(obj.__class__.__name__)
p = set_axis(p=p,x_lim=x_lim,y_lim=y_lim,x_label=x_label,y_label=y_label,title=title,add_hline=add_hline,add_vline=add_vline,add_grid=add_grid,ggtheme=ggtheme)
return p
