lets_plot.geom_bin2d

lets_plot.geom_bin2d(mapping=None, *, data=None, stat=None, position=None, show_legend=None, sampling=None, tooltips=None, bins=None, binwidth=None, drop=None, color_by=None, fill_by=None, **other_args)

Divides the plane into a grid and color the bins by the count of cases in them.

Parameters

mappingFeatureSpec

Set of aesthetic mappings created by aes() function. Aesthetic mappings describe the way that variables in the data are mapped to plot “aesthetics”.

datadict or Pandas or Polars 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.

statstr, default=’bin2d’

The statistical transformation to use on the data for this layer, as a string.

positionstr or FeatureSpec, default=’identity’

Position adjustment, either as a string (‘identity’, ‘stack’, ‘dodge’, …), or the result of a call to a position adjustment function.

show_legendbool, default=True

False - do not show legend for this layer.

samplingFeatureSpec

Result of the call to the sampling_xxx() function. To prevent any sampling for this layer pass value “none” (string “none”).

tooltipslayer_tooltips

Result of the call to the layer_tooltips() function. Specify appearance, style and content.

binslist of int, default=[30, 30]

Number of bins in both directions, vertical and horizontal. Overridden by binwidth.

binwidthlist of float

The width of the bins in both directions, vertical and horizontal. Override bins. The default is to use bin widths that cover the entire range of the data.

dropbool, default=True

Specify whether to remove all bins with 0 counts.

color_by{‘fill’, ‘color’, ‘paint_a’, ‘paint_b’, ‘paint_c’}, default=’color’

Define the color aesthetic for the geometry.

fill_by{‘fill’, ‘color’, ‘paint_a’, ‘paint_b’, ‘paint_c’}, default=’fill’

Define the fill aesthetic for the geometry.

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

LayerSpec

Geom object specification.

Notes

geom_bin2d() applies rectangular grid to the plane then counts observation in each cell of the grid (bin). Uses geom_tile() to display counts as a tile fill-color.

Computed variables:

• ..count.. : number of points with coordinates in the same bin.

geom_bin2d() understands the following aesthetics mappings:

• x : x-axis value.

• y : y-axis value.

• alpha : transparency level of a layer. Accept values between 0 and 1.

• color (colour) : color of the geometry lines. String in the following formats: RGB/RGBA (e.g. “rgb(0, 0, 255)”); HEX (e.g. “#0000FF”); color name (e.g. “red”); role name (“pen”, “paper” or “brush”).

• fill : fill color. String in the following formats: RGB/RGBA (e.g. “rgb(0, 0, 255)”); HEX (e.g. “#0000FF”); color name (e.g. “red”); role name (“pen”, “paper” or “brush”).

• size : line width, default=0 (i.e. tiles outline initially is not visible).

• weight : used by ‘bin’ stat to compute weighted sum instead of simple count.

Examples

import numpy as np
from lets_plot import *
LetsPlot.setup_html()
np.random.seed(42)
mean = np.zeros(2)
cov = np.eye(2)
x, y = np.random.multivariate_normal(mean, cov, 1000).T
ggplot({'x': x, 'y': y}, aes(x='x', y='y')) + geom_bin2d()

import numpy as np
from lets_plot import *
LetsPlot.setup_html()
np.random.seed(42)
n = 5000
x = np.random.uniform(-2, 2, size=n)
y = np.random.normal(scale=.5, size=n)
ggplot({'x': x, 'y': y}, aes(x='x', y='y')) + \
    geom_bin2d(aes(fill='..density..'), binwidth=[.25, .24], \
               tooltips=layer_tooltips().format('@x', '.2f')
                       .format('@y', '.2f').line('(@x, @y)')
                       .line('count|@..count..')
                       .format('@..density..', '.3f')
                       .line('density|@..density..')) + \
    scale_fill_gradient(low='black', high='red')

import numpy as np
from lets_plot import *
LetsPlot.setup_html()
np.random.seed(42)
mean = np.zeros(2)
cov = [[1, .5],
       [.5, 1]]
x, y = np.random.multivariate_normal(mean, cov, 500).T
ggplot({'x': x, 'y': y}, aes(x='x', y='y')) + \
    geom_bin2d(aes(alpha='..count..'), bins=[20, 20], \
               fill='darkgreen') + \
    geom_point(size=1.5, shape=21, color='white', \
               fill='darkgreen') + \
    ggsize(600, 450)

import numpy as np
from lets_plot import *
LetsPlot.setup_html()
np.random.seed(42)
x, y = np.random.multivariate_normal(mean=[-98, 39], cov=[[100, 0], [0, 10]], size=100).T
ggplot() + geom_livemap() + \
    geom_bin2d(aes(x, y, fill='..density..'), \
               bins=[10, 5], alpha=.5, show_legend=False)