Date Axis with C++

Possible Usage Scenarios

When you create a chart from worksheet data that uses dates, and the dates are plotted along the horizontal (category) axis in the chart, Aspose.Cells automatically changes the category axis to a date (time-scale) axis. A date axis displays dates in chronological order at specific intervals or base units, such as the number of days, months, or years, even if the dates on the worksheet are not in sequential order or in the same base units. By default, Aspose.Cells determines the base units for the date axis based on the smallest difference between any two dates in the worksheet data. For example, if you have data for stock prices where the smallest difference between dates is seven days, Aspose.Cells sets the base unit to days, but you can change the base unit to months or years if you want to see the performance of the stock over a longer period of time.

Handle Date Axis like Microsoft Excel

Please see the following sample code that creates a new Excel file and puts values of the chart in the first worksheet. Then we add a chart and set the type of the Axis  to TimeScale and then set the base units to Days.

Sample Code

#include <iostream>
#include "Aspose.Cells.h"
using namespace Aspose::Cells;
using namespace Aspose::Cells::Charts;

int main() {
    Aspose::Cells::Startup();

    // Create an instance of Workbook
    Workbook workbook;

    // Get the first worksheet
    Worksheet worksheet = workbook.GetWorksheets().Get(0);

    // Add the sample values to cells
    worksheet.GetCells().Get(u"A1").PutValue(u"Date");

    // 14 means datetime format
    Style style = worksheet.GetCells().GetStyle();
    style.SetNumber(14);

    // Put values to cells for creating chart
    worksheet.GetCells().Get(u"A2").SetStyle(style);
    worksheet.GetCells().Get(u"A2").PutValue(Date{2022, 6, 26, 0, 0, 0, 0});

    worksheet.GetCells().Get(u"A3").SetStyle(style);
    worksheet.GetCells().Get(u"A3").PutValue(Date{2022, 5, 22, 0, 0, 0, 0});

    worksheet.GetCells().Get(u"A4").SetStyle(style);
    worksheet.GetCells().Get(u"A4").PutValue(Date{2022, 8, 3, 0, 0, 0, 0});

    worksheet.GetCells().Get(u"B1").PutValue(u"Price");
    worksheet.GetCells().Get(u"B2").PutValue(40);
    worksheet.GetCells().Get(u"B3").PutValue(50);
    worksheet.GetCells().Get(u"B4").PutValue(60);

    // Add a chart to the worksheet
    int chartIndex = worksheet.GetCharts().Add(ChartType::Column, 9, 6, 21, 13);

    // Access the instance of the newly added chart
    Chart chart = worksheet.GetCharts().Get(chartIndex);

    // Add SeriesCollection (chart data source) to the chart ranging from "A1" cell to "B4"
    chart.SetChartDataRange(u"A1:B4", true);

    // Set the Axis type to Date time
    chart.GetCategoryAxis().SetCategoryType(CategoryType::TimeScale);

    // Set the base unit for CategoryAxis to days
    chart.GetCategoryAxis().SetBaseUnitScale(TimeUnit::Days);

    // Set the direction for the axis text to be vertical
    chart.GetCategoryAxis().GetTickLabels().SetDirectionType(ChartTextDirectionType::Vertical);

    // Fill the PlotArea area with nothing
    chart.GetPlotArea().GetArea().GetFillFormat().SetFillType(FillType::None);

    // Set max value of Y axis
    chart.GetValueAxis().SetMaxValue(70);

    // Set major unit
    chart.GetValueAxis().SetMajorUnit(10);

    // Save the file
    workbook.Save(u"DateAxis.xlsx");

    Aspose::Cells::Cleanup();
    return 0;
}