How to add a data label that sum my stack histogram

Question

I'm working with pptx to create PowerPoint presentation. I want to add a data label that is the sum of each stack.

I successfully added the value on each different data with this.

if isValueOnGraph :
        plot = chart.plots[0]
        plot.has_data_labels = True
        data_labels = plot.data_labels
        data_labels.font.size = Pt(7)
        data_labels.font.color.rgb = RGBColor(0x0A, 0x42, 0x80)
        if million:
            
            data_labels.number_format = "0.0,,\"M\""
        else:
            data_labels.number_format = '0.00'

Result :

And here is what I want

Bonus point if the totals do not scale up my y axis

Thank you

Answer 1

EDIT:

As a disclaimer I have to say that this is a workaround, but I couldn't achieve what I suggested with the XL_LABEL_POSITION in conbination with XL_CHART_TYPE.COLUMN_STACKED.

I've tried to add another Series to use its text frame as OP intended. Said Series can have different values to increment or decrement its y-axis, since its colour is set to transparent. This is the code with the docs examples:

from pptx import Presentation
from pptx.dml.color import RGBColor
from pptx.chart.data import ChartData
from pptx.enum.chart import XL_LABEL_POSITION
from pptx.enum.chart import XL_CHART_TYPE
from pptx.util import Inches, Pt

prs = Presentation()
slide = prs.slides.add_slide(prs.slide_layouts[5])


chart_data = ChartData()
chart_data.categories = ['East', 'West', 'Midwest']
chart_data.add_series('Q1 Sales', (19.2, 21.4, 16.7))
chart_data.add_series('Q2 Sales', (22.3, 28.6, 15.2))
chart_data.add_series('Q3 Sales', (20.4, 26.3, 14.2))
# Change these values to adjust the labels hight
chart_data.add_series('Total', (10, 10, 10))

x, y, cx, cy = Inches(2), Inches(2), Inches(6), Inches(4.5)

graphic_frame = slide.shapes.add_chart(
    XL_CHART_TYPE.COLUMN_STACKED, x, y, cx, cy, chart_data
)

chart = graphic_frame.chart

plot = chart.plots[0]
plot.has_data_labels = True
data_labels = plot.data_labels

data_labels.font.size = Pt(13)
data_labels.font.color.rgb = RGBColor(0x0A, 0x42, 0x80)
# Workaround:
for point in plot.series[-1].points:
    # Setting each point's bg to transparent
    point.format.fill.background()
    point.data_label.has_text_frame = True
    # Value to display
    point.data_label.text_frame.text = '10000M'

prs.save('chart-01.pptx')

Output:

Original post:

You have to simply specify the location of your data_labels, in your case I think you want to add another label and specify its position with XL_LABEL_POSITION.OUTSIDE_END.

This is my output using the example in the docs

from pptx import Presentation
from pptx.dml.color import RGBColor
from pptx.chart.data import CategoryChartData, ChartData
from pptx.enum.chart import XL_LABEL_POSITION
from pptx.enum.chart import XL_CHART_TYPE
from pptx.util import Inches, Pt

prs = Presentation()
slide = prs.slides.add_slide(prs.slide_layouts[5])


chart_data = ChartData()
chart_data.categories = ['East', 'West', 'Midwest']
chart_data.add_series('Q1 Sales', (19.2, 21.4, 16.7))
chart_data.add_series('Q2 Sales', (22.3, 28.6, 15.2))
chart_data.add_series('Q3 Sales', (20.4, 26.3, 14.2))

x, y, cx, cy = Inches(2), Inches(2), Inches(6), Inches(4.5)
slide.shapes.add_chart(
    XL_CHART_TYPE.COLUMN_CLUSTERED, x, y, cx, cy, chart_data
)

graphic_frame = slide.shapes.add_chart(
    XL_CHART_TYPE.COLUMN_CLUSTERED, x, y, cx, cy, chart_data
)

chart = graphic_frame.chart

plot = chart.plots[0]
plot.has_data_labels = True
data_labels = plot.data_labels

data_labels.font.size = Pt(13)
data_labels.font.color.rgb = RGBColor(0x0A, 0x42, 0x80)
data_labels.position = XL_LABEL_POSITION.OUTSIDE_END


prs.save('chart-01.pptx')