ex_pyplot.py

# https://matplotlib.org/gallery/index.html#pyplot-examples
from __future__ import division


from matplotlib import colors as mcolors
import matplotlib.pyplot as plt
import numpy as np


def easy_subplots():
    x = np.random.randn(50)

    # old style
    fig = plt.figure()
    ax1 = fig.add_subplot(221)
    ax2 = fig.add_subplot(222, sharex=ax1, sharey=ax1)
    ax3 = fig.add_subplot(223, sharex=ax1, sharey=ax1)
    ax3 = fig.add_subplot(224, sharex=ax1, sharey=ax1)

    # new style method 2; use an axes array
    fig, axs = plt.subplots(2, 2, sharex=True, sharey=True)
    axs[0, 0].plot(x)
    plt.show()


def scatter_plot():
    # Fixing random state for reproducibility
    np.random.seed(19680801)

    N = 50
    x = np.random.rand(N)
    y = np.random.rand(N)
    colors = np.random.rand(N)
    area = np.pi * (15 * np.random.rand(N)) ** 2  # 0 to 15 point radii

    plt.scatter(x, y, s=area, c=colors, alpha=0.5)
    plt.show()


def pie_chart():
    # Pie chart, where the slices will be ordered and plotted counter-clockwise:
    labels = 'Frogs', 'Hogs', 'Dogs', 'Logs'
    sizes = [15, 30, 45, 10]
    explode = (0, 0.1, 0, 0)  # only "explode" the 2nd slice (i.e. 'Hogs')

    fig1, ax1 = plt.subplots()
    ax1.pie(sizes, explode=explode, labels=labels, autopct='%1.1f%%',
            shadow=True, startangle=90)
    ax1.axis('equal')  # Equal aspect ratio ensures that pie is drawn as a circle.

    plt.show()


def simple_plot():
    plt.plot([1, 2, 3, 4])
    plt.ylabel('some numbers')
    plt.show()


def annotated_plot():
    ax = plt.subplot(111)

    t = np.arange(0.0, 5.0, 0.01)
    s = np.cos(2 * np.pi * t)
    line, = plt.plot(t, s, lw=2)

    plt.annotate('local max', xy=(2, 1), xytext=(3, 1.5),
                 arrowprops=dict(facecolor='black', shrink=0.05),
                 )

    plt.ylim(-2, 2)
    plt.show()


def histogram_multihist():
    np.random.seed(19680801)

    n_bins = 10
    x = np.random.randn(1000, 3)

    fig, axes = plt.subplots(nrows=2, ncols=2)
    ax0, ax1, ax2, ax3 = axes.flatten()

    colors = ['red', 'tan', 'lime']
    ax0.hist(x, n_bins, normed=1, histtype='bar', color=colors, label=colors)
    ax0.legend(prop={'size': 10})
    ax0.set_title('bars with legend')

    ax1.hist(x, n_bins, normed=1, histtype='bar', stacked=True)
    ax1.set_title('stacked bar')

    ax2.hist(x, n_bins, histtype='step', stacked=True, fill=False)
    ax2.set_title('stack step (unfilled)')

    # Make a multiple-histogram of data-sets with different length.
    x_multi = [np.random.randn(n) for n in [10000, 5000, 2000]]
    ax3.hist(x_multi, n_bins, histtype='bar')
    ax3.set_title('different sample sizes')

    fig.tight_layout()
    plt.show()


def boxplot_violin():
    fig, axes = plt.subplots(nrows=1, ncols=2, figsize=(9, 4))

    # Fixing random state for reproducibility
    np.random.seed(19680801)

    # generate some random test data
    all_data = [np.random.normal(0, std, 100) for std in range(6, 10)]

    # plot violin plot
    axes[0].violinplot(all_data,
                       showmeans=False,
                       showmedians=True)
    axes[0].set_title('Violin plot')

    # plot box plot
    axes[1].boxplot(all_data)
    axes[1].set_title('Box plot')

    # adding horizontal grid lines
    for ax in axes:
        ax.yaxis.grid(True)
        ax.set_xticks([y + 1 for y in range(len(all_data))])
        ax.set_xlabel('Four separate samples')
        ax.set_ylabel('Observed values')

    # add x-tick labels
    plt.setp(axes, xticks=[y + 1 for y in range(len(all_data))],
             xticklabels=['x1', 'x2', 'x3', 'x4'])
    plt.show()


def barchart():
    n_groups = 5

    means_men = (20, 35, 30, 35, 27)
    std_men = (2, 3, 4, 1, 2)

    means_women = (25, 32, 34, 20, 25)
    std_women = (3, 5, 2, 3, 3)

    fig, ax = plt.subplots()

    index = np.arange(n_groups)
    bar_width = 0.35

    opacity = 0.4
    error_config = {'ecolor': '0.3'}

    rects1 = ax.bar(index, means_men, bar_width,
                    alpha=opacity, color='b',
                    yerr=std_men, error_kw=error_config,
                    label='Men')

    rects2 = ax.bar(index + bar_width, means_women, bar_width,
                    alpha=opacity, color='r',
                    yerr=std_women, error_kw=error_config,
                    label='Women')

    ax.set_xlabel('Group')
    ax.set_ylabel('Scores')
    ax.set_title('Scores by group and gender')
    ax.set_xticks(index + bar_width / 2)
    ax.set_xticklabels(('A', 'B', 'C', 'D', 'E'))
    ax.legend()

    fig.tight_layout()
    plt.show()
def named_colors():


    colors = dict(mcolors.BASE_COLORS, **mcolors.CSS4_COLORS)

    # Sort colors by hue, saturation, value and name.
    by_hsv = sorted((tuple(mcolors.rgb_to_hsv(mcolors.to_rgba(color)[:3])), name)
                    for name, color in colors.items())
    sorted_names = [name for hsv, name in by_hsv]

    n = len(sorted_names)
    ncols = 4
    nrows = n // ncols + 1

    fig, ax = plt.subplots(figsize=(8, 5))

    # Get height and width
    X, Y = fig.get_dpi() * fig.get_size_inches()
    h = Y / (nrows + 1)
    w = X / ncols

    for i, name in enumerate(sorted_names):
        col = i % ncols
        row = i // ncols
        y = Y - (row * h) - h

        xi_line = w * (col + 0.05)
        xf_line = w * (col + 0.25)
        xi_text = w * (col + 0.3)

        ax.text(xi_text, y, name, fontsize=(h * 0.8),
                horizontalalignment='left',
                verticalalignment='center')

        ax.hlines(y + h * 0.1, xi_line, xf_line,
                  color=colors[name], linewidth=(h * 0.6))

    ax.set_xlim(0, X)
    ax.set_ylim(0, Y)
    ax.set_axis_off()

    fig.subplots_adjust(left=0, right=1,
                        top=1, bottom=0,
                        hspace=0, wspace=0)
    plt.show()

named_colors()