.. _ticks_and_spines-tick-locators:

ticks_and_spines example code: tick-locators.py
===============================================



.. plot:: /home/tcaswell/src/p/matplotlib/doc/mpl_examples/ticks_and_spines/tick-locators.py

::

    """
    =============
    Tick locators
    =============
    
    Show the different tick locators.
    """
    
    import numpy as np
    import matplotlib.pyplot as plt
    import matplotlib.ticker as ticker
    
    
    # Setup a plot such that only the bottom spine is shown
    def setup(ax):
        ax.spines['right'].set_color('none')
        ax.spines['left'].set_color('none')
        ax.yaxis.set_major_locator(ticker.NullLocator())
        ax.spines['top'].set_color('none')
        ax.xaxis.set_ticks_position('bottom')
        ax.tick_params(which='major', width=1.00)
        ax.tick_params(which='major', length=5)
        ax.tick_params(which='minor', width=0.75)
        ax.tick_params(which='minor', length=2.5)
        ax.set_xlim(0, 5)
        ax.set_ylim(0, 1)
        ax.patch.set_alpha(0.0)
    
    
    plt.figure(figsize=(8, 6))
    n = 8
    
    # Null Locator
    ax = plt.subplot(n, 1, 1)
    setup(ax)
    ax.xaxis.set_major_locator(ticker.NullLocator())
    ax.xaxis.set_minor_locator(ticker.NullLocator())
    ax.text(0.0, 0.1, "NullLocator()", fontsize=14, transform=ax.transAxes)
    
    # Multiple Locator
    ax = plt.subplot(n, 1, 2)
    setup(ax)
    ax.xaxis.set_major_locator(ticker.MultipleLocator(0.5))
    ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.1))
    ax.text(0.0, 0.1, "MultipleLocator(0.5)", fontsize=14,
            transform=ax.transAxes)
    
    # Fixed Locator
    ax = plt.subplot(n, 1, 3)
    setup(ax)
    majors = [0, 1, 5]
    ax.xaxis.set_major_locator(ticker.FixedLocator(majors))
    minors = np.linspace(0, 1, 11)[1:-1]
    ax.xaxis.set_minor_locator(ticker.FixedLocator(minors))
    ax.text(0.0, 0.1, "FixedLocator([0, 1, 5])", fontsize=14,
            transform=ax.transAxes)
    
    # Linear Locator
    ax = plt.subplot(n, 1, 4)
    setup(ax)
    ax.xaxis.set_major_locator(ticker.LinearLocator(3))
    ax.xaxis.set_minor_locator(ticker.LinearLocator(31))
    ax.text(0.0, 0.1, "LinearLocator(numticks=3)",
            fontsize=14, transform=ax.transAxes)
    
    # Index Locator
    ax = plt.subplot(n, 1, 5)
    setup(ax)
    ax.plot(range(0, 5), [0]*5, color='White')
    ax.xaxis.set_major_locator(ticker.IndexLocator(base=.5, offset=.25))
    ax.text(0.0, 0.1, "IndexLocator(base=0.5, offset=0.25)",
            fontsize=14, transform=ax.transAxes)
    
    # Auto Locator
    ax = plt.subplot(n, 1, 6)
    setup(ax)
    ax.xaxis.set_major_locator(ticker.AutoLocator())
    ax.xaxis.set_minor_locator(ticker.AutoMinorLocator())
    ax.text(0.0, 0.1, "AutoLocator()", fontsize=14, transform=ax.transAxes)
    
    # MaxN Locator
    ax = plt.subplot(n, 1, 7)
    setup(ax)
    ax.xaxis.set_major_locator(ticker.MaxNLocator(4))
    ax.xaxis.set_minor_locator(ticker.MaxNLocator(40))
    ax.text(0.0, 0.1, "MaxNLocator(n=4)", fontsize=14, transform=ax.transAxes)
    
    # Log Locator
    ax = plt.subplot(n, 1, 8)
    setup(ax)
    ax.set_xlim(10**3, 10**10)
    ax.set_xscale('log')
    ax.xaxis.set_major_locator(ticker.LogLocator(base=10.0, numticks=15))
    ax.text(0.0, 0.1, "LogLocator(base=10, numticks=15)",
            fontsize=15, transform=ax.transAxes)
    
    # Push the top of the top axes outside the figure because we only show the
    # bottom spine.
    plt.subplots_adjust(left=0.05, right=0.95, bottom=0.05, top=1.05)
    
    plt.show()
    

Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)