How to change font size of chart title and axis title ?

[DrFunn1]

There are two methods to style chart text elements. Axis numbers can be styled using chart.text RichText properties and chart titles using drawing.text ParagraphProperties. The legend can be styled using either method.

from openpyxl.chart import ScatterChart, Reference, Series
from openpyxl.chart.text import RichText
from openpyxl.drawing.text import Paragraph, ParagraphProperties, CharacterProperties, RichTextProperties, Font, RegularTextRun

# Set up basic XY Scatter Chart
chart = ScatterChart()
chart.title = "Scatter Chart"
chart.style = 2 # Excel menu chart tools: Design > Chart Styles
chart.x_axis.title = 'X-axis Title'
chart.y_axis.title = 'Primary Y-axis Title'

# Style chart
# X and Y axes numbers
font = Font(typeface='Verdana')
size = 1400 # 14 point size
cp = CharacterProperties(latin=font, sz=size, b=False) # Not bold
pp = ParagraphProperties(defRPr=cp)
rtp = RichText(p=[Paragraph(pPr=pp, endParaRPr=cp)])
chart.x_axis.txPr = rtp        # Works!
chart.y_axis.txPr = rtp        # Works!

# X and Y axes titles
chart.x_axis.title.tx.rich.p[0].pPr = pp       # Works!
chart.y_axis.title.tx.rich.p[0].pPr = pp       # Works!