# Plotly Stacked Area Chart

This tutorial will discuss creating a stacked area chart using the `stackgroup` parameter of the `scatter()` function of Plotly.

## Plotly Stacked Area Plot

A stacked area chart contains more than one area of different data frames. We can plot more than one area on the same graph using the `stackgroup()` parameter of the `scatter()` function.

After creating a scatter plot, we can add another area using the `add_trace()` function, which adds data in the same figure.

For example, let’s use some random data to create a scatter plot and then add another area using the `add_trace()` function. See the code below.

``````import plotly.graph_objects as go

x = [1, 2, 3, 4]
plot = px.Figure(go.Scatter(name='Data One',x = x,
y = [100, 200, 500, 673],stackgroup='one'))

name = 'Data Two',
x = x,
y = [56, 123, 982, 213],
stackgroup='one'))

plot.show()
``````

Output: We can also change the normalization of the graph using the `groupnorm` argument and setting its value to percent for the sum of the stack group.

For example, let’s plot the above graph using normalized values. See the code below.

``````import plotly.graph_objects as go

x = [1, 2, 3, 4]
plot = px.Figure(go.Scatter(name='Data One',x = x,
y = [100, 200, 500, 673],stackgroup='one',groupnorm='percent'))

name = 'Data Two',
x = x,
y = [56, 123, 982, 213],
stackgroup='one'))

plot.show()
``````

Output: We can use the `add_trace()` function to add another area into the scatter plot after it is created. Still, we can also do that while creating the figure by saving the data inside a variable and then using that variable to plot the stacked area plot.

For example, let’s create the stacked area plot again. See the code below.

``````import plotly.graph_objects as go

x = [1, 2, 3, 4]
data=[go.Scatter(name='Data One',x = x,
y = [100, 200, 500, 673],stackgroup='one'),
go.Scatter(
name = 'Data Two',
x = x,
y = [56, 123, 982, 213],
stackgroup='one')]

plot = px.Figure(data)
plot.show()
``````

Output: Author: Ammar Ali

Hello! I am Ammar Ali, a programmer here to learn from experience, people, and docs, and create interesting and useful programming content. I mostly create content about Python, Matlab, and Microcontrollers like Arduino and PIC.