Plotting with Pandas#

easychart natively supports pd.Series and pd.DataFrame objects. Each pd.Series or pd.DataFrame is treated as a single series, and each row will be handled as a data point. Numeric values from a pd.Index will be used as the x coordinates, although you can override this.

import pandas as pd
import easychart

data = pd.Series([(x - 20) ** 2 + 3 for x in range(10, 30)], index=range(10, 30))

chart = easychart.new()
chart.plot(data)
chart

Here’s an example from a pd.DataFrame.

import easychart
import pandas as pd

grades = pd.DataFrame(
    [[68, 87], [71, 85]], columns=["min", "max"], index=["male", "female"]
)

chart = easychart.new("columnrange")
chart.categories = grades.index
chart.plot(grades, name="min-max range of grades")
chart

Important

The number of columns of the pd.DataFrame must be appropriate for the series type.

For example:

  • a line series requires an (x, y) value for each point, so 2 columns (or 1 column and the pd.Index) are expected

  • a columnrange series requires an (x, min, max) value for each point, so 3 columns (or 2 columns and the pd.Index) are expected

  • a bubble series requires an (x, y, z) value for each point, so 3 columns (or 2 columns and the pd.Index) are expected

import math
import pandas as pd
import easychart

numbers = pd.DataFrame([[x, math.cos(x)] for x in range(-100, 100)])

chart = easychart.new("scatter")
chart.plot(numbers.values)  # 2 columns only (no index)
chart

import math
import pandas as pd
import easychart

numbers = pd.DataFrame(
    [[math.cos(x), math.sin(x)] for x in range(-10, 10)], index=range(-10, 10)
)

chart = easychart.new("bubble")
chart.plot(numbers)  # index + 2 columns
chart

You can override the index of the data by explicitly passing an index argument. In the below example, we override the x coordinates to the range 100 to 130.

import pandas as pd
import easychart

data = pd.Series([(x - 20) ** 2 + 3 for x in range(10, 30)], index=range(10, 30))

chart = easychart.new()
chart.plot(data, index=range(100, 130))
chart

Alternatively, you can drop the index by calling the values property of the pandas objects.

Important

This is particularly relevant for scatter plots drawn from two columns of a pd.DataFrame objects.

import math
import pandas as pd
import easychart

numbers = pd.DataFrame([[x, math.cos(x)] for x in range(-100, 100)])

chart = easychart.new("scatter")
chart.plot(numbers.values)  # 2 columns only (no index)
chart

In the below example, we drop the index, and the x coordinates default to the range [0...n].

import pandas as pd
import easychart

data = pd.Series([(x - 20) ** 2 + 3 for x in range(10, 30)], index=range(10, 30))

chart = easychart.new()
chart.plot(data.values)
chart