Feature request: Add support for Chart date axes

[jmcnamara]

Add functionality like Python XlsxWriter Data Axes.

See http://xlsxwriter.readthedocs.io/working_with_charts.html#date-category-axes

• Add date axis
• Add date min and max
• Add minor_unit_type
• Add major_unit_type

• Difficulty: 2 (Easy 1 - 5 Hard)
• Priority: 2 (High 1 - 5 Low)

Add +1 as a comment to vote for this feature and to get an update when it is implemented.

[ragundo]

+1
Needed for daily/month/year reports generation

[ale275]

+1
perfect for report and trend analysis

[jmcnamara]

Hi,

Note, it is currently possible to use an implicit date axis by using date input data for the X-axis, see the example below. This Feature Request is mainly to add an explicit chart date axis option (like Excel) to enable max and min values and a few other features. Also note, the max and min is also currently available if you use a scatter chart (although the units won't be clear).

Example:

#include "xlsxwriter.h"

/* Create a worksheet with a chart. */
int main() {

    lxw_workbook  *workbook  = new_workbook("chart_date.xlsx");
    lxw_worksheet *worksheet = workbook_add_worksheet(workbook, NULL);


    /* Add an Excel date format. */
    lxw_format *date_format = workbook_add_format(workbook);
    format_set_num_format(date_format, "yyyy-mm-dd");

    /* Widen the first column to make the text clearer. */
    worksheet_set_column(worksheet, 0, 0, 20, NULL);

    /* Write some data for the chart. */
    lxw_datetime datetime1 = {.year = 2016, .month = 1, .day = 13};
    lxw_datetime datetime2 = {.year = 2016, .month = 1, .day = 14};
    lxw_datetime datetime3 = {.year = 2016, .month = 1, .day = 15};
    lxw_datetime datetime4 = {.year = 2016, .month = 1, .day = 16};
    lxw_datetime datetime5 = {.year = 2016, .month = 1, .day = 17};
    lxw_datetime datetime6 = {.year = 2016, .month = 1, .day = 18};
    lxw_datetime datetime7 = {.year = 2016, .month = 1, .day = 19};

    worksheet_write_datetime(worksheet, 0, 0, &datetime1, date_format);
    worksheet_write_datetime(worksheet, 1, 0, &datetime2, date_format);
    worksheet_write_datetime(worksheet, 2, 0, &datetime3, date_format);
    worksheet_write_datetime(worksheet, 3, 0, &datetime4, date_format);
    worksheet_write_datetime(worksheet, 4, 0, &datetime5, date_format);
    worksheet_write_datetime(worksheet, 5, 0, &datetime6, date_format);
    worksheet_write_datetime(worksheet, 6, 0, &datetime7, date_format);

    worksheet_write_number(worksheet, 0, 1, 10, NULL);
    worksheet_write_number(worksheet, 1, 1, 20, NULL);
    worksheet_write_number(worksheet, 2, 1, 30, NULL);
    worksheet_write_number(worksheet, 3, 1, 10, NULL);
    worksheet_write_number(worksheet, 4, 1, 30, NULL);
    worksheet_write_number(worksheet, 5, 1, 10, NULL);
    worksheet_write_number(worksheet, 6, 1, 20, NULL);

    /* Create a chart object. */
    lxw_chart *chart = workbook_add_chart(workbook, LXW_CHART_COLUMN);

    /* Add a chart series. */
    chart_add_series(chart, "=Sheet1!$A$1:$A$7", "=Sheet1!$B$1:$B$7");

    /* Rotate the axis data text to make it easier to read. */
    lxw_chart_font font = {.rotation = -30};
    chart_axis_set_num_font(chart->x_axis, &font);

    /* Insert the chart into the worksheet. */
    worksheet_insert_chart(worksheet, CELL("D2"), chart);

    return workbook_close(workbook);
}

Output: