CODEWITHSUNDEEP
pythonexcelopenpyxl
D.Blaz
D.Blaz

Reputation: 23

openpyxl trendline and R-squared value

I'm trying to add "linear" trend-line to my excel chart and display R-squared value using openpyxl, but i cannot find any example.

Below is python code that generates chart shown on image without trend-line and R-squared formula chart image.

Thanks!

from openpyxl import Workbook, load_workbook
from openpyxl.chart import (
    ScatterChart,
    Reference,
    Series,
)
from openpyxl.chart.trendline import Trendline


wb = load_workbook(r"path to load blank workbook\data.xlsx")
ws = wb.active

rows = [
    ['Size', 'Batch 1'],
    [3, 40],
    [4, 50],
    [2, 40],
    [5, 30],
    [6, 25],
    [7, 20],
]

for row in rows:
    ws.append(row)

chart = ScatterChart()
chart.title = "Scatter Chart"
#chart.style = 13
chart.x_axis.title = 'Size'
chart.y_axis.title = 'Percentage'



xvalues = Reference(ws, min_col=1, min_row=2, max_row=8)
for i in range(2, 4):
    values = Reference(ws, min_col=i, min_row=2, max_row=8)
    series = Series(values, xvalues, title_from_data=True)
    chart.series.append(series)



line = chart.series[0]
line.graphicalProperties.line.noFill = True
line.marker.symbol = "circle"


ws.add_chart(chart, "A10")

wb.save("path to save workbook\scatter.xlsx")

Upvotes: 2

Views: 2317

Answers (1)

Charlie Clark
Charlie Clark

Reputation: 19527

It's basically impossible to document all the possibilities for charts so you will occasionally have to dive into the XML of a relevant chart to find out how it's done. That said, trendlines are pretty easy to do.

from openpyxl.chart.trendline import Trendline
line.trendline = Trendline()

Upvotes: 3

Related Questions