A line shows a series of data points connected with a line along the X-axis. It is an independent axis because the values on the X-axis do not depend on the vertical Y-axis.

The Y-axis is a dependent axis because its values depend on the X-axis and the result is the line that progress horizontally.

Working with XlsxWriter Line Chart

To generate the line chart programmatically using XlsxWriter, we use add_series(). The type of chart object is defined as ”line”.

Example

In the following example, we shall plot line chart showing the sales figures of two products over six months. Two data series corresponding to sales figures of Product A and Product B are added to the chart with add_series() method.

import xlsxwriter

wb = xlsxwriter.Workbook(''hello.xlsx'')
worksheet = wb.add_worksheet()
headings = [''Month'', ''Product A'', ''Product B'']

data = [
   [''Jan'', ''Feb'', ''Mar'', ''Apr'', ''May'', ''June''],
   [10, 40, 50, 20, 10, 50],
   [30, 60, 70, 50, 40, 30],
]

bold=wb.add_format({''bold'':True})
worksheet.write_row(''A1'', headings, bold)
worksheet.write_column(''A2'', data[0])
worksheet.write_column(''B2'', data[1])
worksheet.write_column(''C2'', data[2])

chart1 = wb.add_chart({''type'': ''line''})

chart1.add_series({
   ''name'': ''=Sheet1!$B$1'',
   ''categories'': ''=Sheet1!$A$2:$A$7'',
   ''values'': ''=Sheet1!$B$2:$B$7'',
})
chart1.add_series({
   ''name'': [''Sheet1'', 0, 2],
   ''categories'': [''Sheet1'', 1, 0, 6, 0],
   ''values'': [''Sheet1'', 1, 2, 6, 2],
})
chart1.set_title ({''name'': ''Sales analysis''})
chart1.set_x_axis({''name'': ''Months''})
chart1.set_y_axis({''name'': ''Units''})

worksheet.insert_chart(''D2'', chart1)

wb.close()

Output

After executing the above program, here is how XlsxWriter generates the Line chart −

Along with data_labels, the add_series() method also has a marker property. This is especially useful in a line chart. The data points are indicated by marker symbols such as a circle, triangle, square, diamond etc. Let us assign circle and square symbols to the two data series in this chart.

chart1.add_series({
   ''name'': ''=Sheet1!$B$1'',
   ''categories'': ''=Sheet1!$A$2:$A$7'',
   ''values'': ''=Sheet1!$B$2:$B$7'',
   ''data_labels'': {''value'': True},
   ''marker'': {''type'': ''circle''},
})
chart1.add_series({
   ''name'': [''Sheet1'', 0, 2],
   ''categories'': [''Sheet1'', 1, 0, 6, 0],
   ''values'': [''Sheet1'', 1, 2, 6, 2],
   ''data_labels'': {''value'': True},
   ''marker'': {''type'': ''square''},})

The data labels and markers are added to the line chart.

Line chart also supports stacked and percent_stacked subtypes.