Plotly is a Python library which is used to design graphs, especially interactive graphs. It can plot various graphs and charts like histogram, barplot, boxplot, spreadplot and many more. It is mainly used in data analysis as well as financial analysis. Plotly is an interactive visualization library.
Scatter Plot
A scatter plot is a diagram where each value is represented by the dot graph. Scatter plot needs arrays for the same length, one for the value of x-axis and other value for the y-axis. Each data is represented as a dot point, whose location is given by x and y columns. It can be created using the scatter() method of plotly.express
Syntax: plotly.express.scatter(data_frame=None, x=None, y=None, color=None, symbol=None, size=None, hover_name=None, hover_data=None, custom_data=None, text=None, facet_row=None, facet_col=None, facet_col_wrap=0, error_x=None, error_x_minus=None, error_y=None, error_y_minus=None, animation_frame=None, animation_group=None, category_orders={}, labels={}, orientation=None, color_discrete_sequence=None, color_discrete_map={}, color_continuous_scale=None, range_color=None, color_continuous_midpoint=None, symbol_sequence=None, symbol_map={}, opacity=None, size_max=None, marginal_x=None, marginal_y=None, trendline=None, trendline_color_override=None, log_x=False, log_y=False, range_x=None, range_y=None, render_mode=’auto’, title=None, template=None, width=None, height=None)
Parameters:
| Name | Value | Description |
|---|---|---|
| x, y | array_like, shape (n, ) | The data positions |
| s | scalar or array_like, shape (n, ), optional | The marker size in points**2. Default is rcParams[‘lines.markersize’] ** 2. |
| c | color, sequence, or sequence of color, optional |
The marker color. Possible values: A single color format string. A sequence of color specifications of length n. A sequence of n numbers to be mapped to colors using cmap and norm. A 2-D array in which the rows are RGB or RGBA |
| marker | MarkerStyle, optional | The marker style. marker can be either an instance of the class or the text shorthand for a particular marker. Defaults to None, in which case it takes the value of rcParams[“scatter.marker”] = ‘o’ = ‘o’. See markers for more information about marker styles. |
Example:
Python3
import plotly.express as px import numpy as np # creating random data through randomint # function of numpy.random np.random.seed(42) random_x= np.random.randint(1,101,100) random_y= np.random.randint(1,101,100) plot = px.scatter(random_x, random_y) plot.show() |
Output:
Changing color
Color of dots of the scatter plot can be changed using the color argument of the scatter() method.
Example: We will use the built-in iris dataset.
Python3
import plotly.express as px # Loading the iris dataset df = px.data.iris() fig = px.scatter(df, x="sepal_width", y="sepal_length", color="species") fig.show() |
Output:
Changing Size
The size of the dots of the scatter plot can be changed using the size argument of the scatter() method.
Example:
Python3
import plotly.express as px # Loading the iris dataset df = px.data.iris() fig = px.scatter(df, x="sepal_width", y="sepal_length", color="species", size='petal_length', hover_data=['petal_width']) fig.show() |
Output:
