Source code for pandas_visual_analysis.widgets.parcoords

import numbers

import ipywidgets as widgets
import numpy as np
import pandas as pd
import plotly.graph_objs as go
from plotly.callbacks import Points

from pandas_visual_analysis import DataSource
from pandas_visual_analysis.data_source import SelectionType
from pandas_visual_analysis.utils.config import Config
from pandas_visual_analysis.widgets import BaseWidget, register_widget
from pandas_visual_analysis.widgets.helpers.multi_select import (

[docs]@register_widget class ParallelCoordinatesWidget(BaseWidget, HasMultiSelect): """ The ParallelCoordinatesWidget shows a parallel coordinates plot for high dimensional data and supports brushing. Only displays numerical columns, which can be reordered arbitrarily. Displays a multi column selection if there are too many columns to display them all at once. """ def __init__( self, data_source: DataSource, row: int, index: int, relative_size: float, max_height: int, ): """ :param data_source: :class:`pandas_visual_analysis.data_source.DataSource` for the widget. :param row: The row the widget is in. :param index: Index of the row the widget is in. :param relative_size: The space the widget has in a row which is then converted to the width. (e.g. 0.33 => 33%) :param max_height: height in pixels the plot has to have """ super(ParallelCoordinatesWidget, self).__init__( data_source, row, index, relative_size, max_height ) super(BaseWidget, self).__init__( self.data_source.numerical_columns, relative_size, max_height ) if len(self.columns) < 1: raise ValueError( "The data contains too few numerical columns to display a parallel coordinates plot." "Remove the widget from the layout!" ) if self.use_multi_select: self.multi_select_toggle: widgets.Button = widgets.Button( description="Hide Selection" ) # self.multi_select_toggle.on_click(callback=self._toggle_multi_select) self.trace, self.figure_widget = self._get_figure_widget() self.constraint_ranges = {} self.change_initiated = False def f(x, y): pass self.pass_func = f self.set_observers() # set root here because need to toggle the select and need widgets for that self.root: widgets.Widget = widgets.HBox( [self.figure_widget], layout=widgets.Layout(width="100%") ) if self.multi_select: self.root = widgets.HBox([self.figure_widget, self.multi_select_widget]) if self.data_source.few_num_cols: pass # todo: implement behaviour for few numerical columns (HTML message)
[docs] def build(self): return self.apply_size_constraints(self.root)
[docs] def observe_brush_indices_change(self, sender): if not self.change_initiated: # shortly disable selection behaviour to reset constraint ranges[0].on_change(self.pass_func, "dimensions") with self.figure_widget.batch_update(), self.figure_widget.hold_trait_notifications(): for dimension in[0].dimensions: dimension["constraintrange"] = None[0].on_change( self._on_selection_helper, "dimensions" ) self.constraint_ranges = {} self.change_initiated = False new_indices = list(self.data_source.brushed_indices) new_color = np.zeros(self.data_source.len, dtype="uint8") new_color[new_indices] = 1 with self.figure_widget.batch_update(), self.figure_widget.hold_trait_notifications():[0].line.color = new_color
[docs] def set_observers(self): self.data_source.on_indices_changed.connect(self.observe_brush_indices_change) if self.use_multi_select: self.multi_select.on_selected_options_changed.connect( self._on_selected_columns_changed )
[docs] def on_selection(self, trace, points, state): self.change_initiated = True if self.data_source.selection_type in { SelectionType.ADDITIVE, SelectionType.SUBTRACTIVE, }: self.change_initiated = False # we want to remove constraint ranges in observe_brush_indices_change new_color = np.zeros(self.data_source.len, dtype="uint8") new_color[points.point_inds] = 1 with self.figure_widget.batch_update(), self.figure_widget.hold_trait_notifications():[0].line.color = new_color self.data_source.brushed_indices = points.point_inds
def _on_selection_helper(self, obj, dimensions): old_ranges = self.constraint_ranges self.constraint_ranges = { dim["label"]: dim["constraintrange"] for dim in dimensions if dim["constraintrange"] } if self.constraint_ranges == old_ranges: return # this is the case when the user just reorders the dimensions if len(list(self.constraint_ranges.keys())) == 0: self.on_deselection(None, None) return mask = self._get_constraint_mask(self.constraint_ranges) points = np.arange(self.data_source.len)[mask].tolist() self.on_selection(None, Points(point_inds=points), None) def _get_constraint_mask(self, constraint_ranges: dict) -> np.array: cols = list(constraint_ranges.keys()) mask: np.array = np.full(self.data_source.len, fill_value=True, dtype=bool) for col in cols: range_tuple = constraint_ranges[col] if all(isinstance(x, numbers.Number) for x in range_tuple): range_tuple = (range_tuple,) intermediate_mask: np.array = np.full( self.data_source.len, fill_value=False, dtype=bool ) # for several constraints in one dimension for ranges in range_tuple: intermediate_mask |= ([col].between(ranges[0], ranges[1]) ).values mask &= intermediate_mask return mask
[docs] def on_deselection(self, trace, points): self.data_source.reset_selection()
def _get_par_coords(self) -> go.Parcoords: config = Config() self.trace: go.Parcoords = go.Parcoords( line=dict( color=config.color_scale[1][1], colorscale=config.color_scale, cmin=0, cmax=1, ), dimensions=[self._get_dimension_dict(col) for col in self.selected_columns], ) return self.trace def _get_figure_widget(self): trace: go.Parcoords = self._get_par_coords() figure_widget: go.FigureWidget = go.FigureWidget( data=[self.trace], layout=go.Layout( margin=dict(l=50, r=50, b=30, t=50, pad=10), autosize=True, xaxis=dict(automargin=True), showlegend=False, ), )[0].on_change(self._on_selection_helper, "dimensions") return trace, figure_widget def _get_dimension_dict(self, col: str) -> dict: series: pd.Series =[col] return dict(range=[series.min(), series.max()], label=col, values=series) # def _toggle_multi_select(self, obj): # if self.multi_select: # self.show_multi_select = not self.show_multi_select # button_description = "Hide" if self.show_multi_select else "Show" # self.multi_select_toggle.description = button_description + " Selection" # # if self.show_multi_select: # children = (self.figure_widget, self.multi_select_widget) # else: # children = (self.figure_widget,) # self.root.children = (self.multi_select_toggle, widgets.HBox(children)) def _on_selected_columns_changed(self, sender): self.selected_columns = sender.selected_options self._redraw_plot() def _redraw_plot(self): # shortly disable selection behaviour to reset constraint ranges[0].on_change(self.pass_func, "dimensions") old_constraint_ranges = { dim["label"]: dim["constraintrange"] for dim in[0].dimensions if dim["constraintrange"] } with self.figure_widget.batch_update(), self.figure_widget.hold_trait_notifications():[0].dimensions = [ self._get_dimension_dict(col) for col in self.selected_columns ] # add old constraint ranges to plot for dim in[0].dimensions: if dim["label"] in old_constraint_ranges.keys(): dim["constraintrange"] = old_constraint_ranges[dim["label"]] # if constraint ranges were removed by deselecting a column with a constraint update selection # only updates if constraint ranges actually change, else it returns without updating the selection self._on_selection_helper( None,[0].dimensions )[0].on_change(self._on_selection_helper, "dimensions")