lets_plot.geom_density2d¶
- lets_plot.geom_density2d(mapping=None, *, data=None, stat=None, position=None, show_legend=None, sampling=None, tooltips=None, kernel=None, adjust=None, bw=None, n=None, bins=None, binwidth=None, **other_args)¶
Display density function contour.
- Parameters
mapping (FeatureSpec) – Set of aesthetic mappings created by aes() function. Aesthetic mappings describe the way that variables in the data are mapped to plot “aesthetics”.
data (dict or DataFrame) – The data to be displayed in this layer. If None, the default, the data is inherited from the plot data as specified in the call to ggplot.
stat (str, default=’density2d’) – The statistical transformation to use on the data for this layer, as a string.
position (str or FeatureSpec) – Position adjustment, either as a string (‘identity’, ‘stack’, ‘dodge’, …), or the result of a call to a position adjustment function.
show_legend (bool, default=True) – False - do not show legend for this layer.
sampling (FeatureSpec) – Result of the call to the sampling_xxx() function. Value None (or ‘none’) will disable sampling for this layer.
tooltips (layer_tooltips) – Result of the call to the layer_tooltips() function. Specifies appearance, style and content.
kernel (str, default=’gaussian’) – The kernel we use to calculate the density function. Choose among ‘gaussian’, ‘cosine’, ‘optcosine’, ‘rectangular’ (or ‘uniform’), ‘triangular’, ‘biweight’ (or ‘quartic’), ‘epanechikov’ (or ‘parabolic’).
bw (str or list of float) – The method (or exact value) of bandwidth. Either a string (choose among ‘nrd0’ and ‘nrd’), or a float array of length 2.
adjust (float) – Adjust the value of bandwidth my multiplying it. Changes how smooth the frequency curve is.
n (list of int) – The number of sampled points for plotting the function (on x and y direction correspondingly).
bins (int) – Number of levels.
binwidth (float) – Distance between levels.
other_args – Other arguments passed on to the layer. These are often aesthetics settings used to set an aesthetic to a fixed value, like color=’red’, fill=’blue’, size=3 or shape=21. They may also be parameters to the paired geom/stat.
- Returns
Geom object specification.
- Return type
LayerSpec
Note
geom_density2d() draws density function.
Computed variables:
..group.. : number of density estimate contour line.
geom_density2d() understands the following aesthetics mappings:
x : x-axis coordinates.
y : y-axis coordinates.
alpha : transparency level of a layer. Understands numbers between 0 and 1.
color (colour) : color of a geometry lines. Can be continuous or discrete. For continuous value this will be a color gradient between two colors.
size : lines width. Defines line width.
linetype : type of the line of border. Codes and names: 0 = ‘blank’, 1 = ‘solid’, 2 = ‘dashed’, 3 = ‘dotted’, 4 = ‘dotdash’, 5 = ‘longdash’, 6 = ‘twodash’.
Note
‘density2d’ statistical transformation combined with parameter value contour=False could be used to draw heatmaps (see the example below).
Examples
1import numpy as np 2from lets_plot import * 3LetsPlot.setup_html() 4n = 1000 5np.random.seed(42) 6x = np.random.normal(size=n) 7y = np.random.normal(size=n) 8ggplot({'x': x, 'y': y}, aes('x', 'y')) + \ 9 geom_density2d()