examples.rst

.. currentmodule:: nc_time_axis

Examples

Basic Usage

nc-time-axis works by adding converters to the flexible `units registry`_ of `matplotlib`_. To register its converters, simply import nc_time_axis. Then you will be able to make plots with :py:class:`cftime.datetime` axes.

.. ipython:: python
    :okwarning:

    import cftime
    import matplotlib.pyplot as plt
    import nc_time_axis
    import numpy as np

    fig, ax = plt.subplots(1, 1)
    x = np.linspace(0, 6 * np.pi)
    y = 0.5 * x + np.sin(x)
    times = cftime.num2date(x, units="days since 2000-01-01", calendar="noleap")
    ax.plot(times, y);

    @savefig basic.png
    fig.show()

Setting the Axes Ticks and Tick Format

In the first example, the ticks and tick label formats were chosen automatically using heuristics in nc-time-axis. If you would like to explicitly set the tick positions and label format you may do so using :py:meth:`matplotlib.axes.Axes.set_xticks` and :py:class:`CFTimeFormatter`. The :py:class:`CFTimeFormatter` takes in a date format string (see the Python documentation for acceptable format codes) and the calendar type of the axis (see the :py:class:`cftime.datetime` documentation for valid calendar strings).

.. ipython:: python
    :okwarning:

    fig, ax = plt.subplots(1, 1)
    ax.plot(times, y);
    ax.set_xticks([cftime.datetime(2000, 1, day, calendar="noleap") for day in range(2, 19, 4)]);
    formatter = nc_time_axis.CFTimeFormatter("%m-%d %H:%M", "noleap")
    ax.xaxis.set_major_formatter(formatter)

    @savefig set_ticks.png
    fig.show()