LoginSignup
5
4

More than 3 years have passed since last update.

@hiedaeih(hiedaeih)

Matplotlib Tips - 基本プロット編 -

Last updated at Posted at 2021-03-29

ここではMatplotlibの基本的なプロットの部品をまとめていきます。
基本的な項目としては、日本語表示、図枠、図の配置、軸、目盛り、マーカーとライン、凡例あたりかなと思います。（Matplotlibにはたくさんの機能がありますが、まずはこのあたりが自由自在に作れるのが基本と思います。）
解説については、冒頭に挙げた参考ページに詳しく書いてあります。また、各項目にもリンクを貼ってあります。項目ごとのリンク集としても使えるかなと思います。

まだ途中ですが、随時更新していきます。

動作確認：Python 3.7.9､Matplotlib 3.3.1

よく参考にするページ

日本語表示

import matplotlib.pyplot as plt
import numpy as np
%matplotlib inline

# 日本語の使用
from matplotlib import rcParams
rcParams['font.family'] = 'sans-serif'
rcParams['font.sans-serif'] = ['Meirio', 'Hiragino Maru Gothic Pro', 'Yu Gothic', 
                               'Takao', 'IPAexGothic', 'IPAPGothic', 
                               'VL PGothic', 'Noto Sans CJK JP']

色の設定

目盛（Major Ticks､ Minor Ticks）のカスタマイズ

-『Python Data Science Handbook』（英語の無料オンライン版あり） ｢4.12 目盛のカスタマイズ｣

目盛（Tick Locator）の設定

-Tick locators(matplotlib.orgより)

tick-locators.png

#https://matplotlib.org/stable/gallery/ticks_and_spines/tick-locators.htmlを編集

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker

#日本語fontの設定
from matplotlib import rcParams
rcParams['font.family'] = 'sans-serif'
rcParams['font.sans-serif'] = ['Meirio', 'Hiragino Maru Gothic Pro', 'Yu Gothic', 
                               'Takao', 'IPAexGothic', 'IPAPGothic', 
                               'VL PGothic', 'Noto Sans CJK JP']


def setup(ax, title):
    """Set up common parameters for the Axes in the example."""
    # only show the bottom spine
    ax.yaxis.set_major_locator(ticker.NullLocator())
    ax.spines['right'].set_color('none') #ver.3.4.1では、ax.spines.right.set_color('none')
    ax.spines['left'].set_color('none') #ver.3.4.1では、ax.spines.left.set_color('none')
    ax.spines['top'].set_color('none') #ver.3.4.1では、ax.spines.top.set_color('none')

    ax.xaxis.set_ticks_position('bottom')
    ax.tick_params(which='major', width=1.00, length=5)
    ax.tick_params(which='minor', width=0.75, length=2.5)
    ax.set_xlim(0, 5)
    ax.set_ylim(0, 1)
    ax.text(0.0, 0.2, title, transform=ax.transAxes,
            fontsize=14, color='tab:blue')


fig, axs = plt.subplots(8, 1, figsize=(8, 6))

# Null Locator
setup(axs[0], title="NullLocator() 目盛の非表示")
axs[0].xaxis.set_major_locator(ticker.NullLocator())
axs[0].xaxis.set_minor_locator(ticker.NullLocator())

# Multiple Locator
setup(axs[1], title="MultipleLocator(0.5)  倍数目盛")
axs[1].xaxis.set_major_locator(ticker.MultipleLocator(0.5))
axs[1].xaxis.set_minor_locator(ticker.MultipleLocator(0.1))

# Fixed Locator
setup(axs[2], title="FixedLocator([0, 1, 5]) リストで固定された目盛")
axs[2].xaxis.set_major_locator(ticker.FixedLocator([0, 1, 5]))
axs[2].xaxis.set_minor_locator(ticker.FixedLocator(np.linspace(0.2, 0.8, 4)))

# Linear Locator
setup(axs[3], title="LinearLocator(numticks=3)  minからmaxまで等間隔の目盛")
axs[3].xaxis.set_major_locator(ticker.LinearLocator(3))
axs[3].xaxis.set_minor_locator(ticker.LinearLocator(31))

# Index Locator
setup(axs[4], title="IndexLocator(base=0.5, offset=0.25)  indexをもつ目盛")
axs[4].plot(range(0, 5), [0]*5, color='white')
axs[4].xaxis.set_major_locator(ticker.IndexLocator(base=0.5, offset=0.25))

# MaxN Locator
setup(axs[5], title="MaxNLocator(n=4)  最大値に適切に割り振られた目盛")
axs[5].xaxis.set_major_locator(ticker.MaxNLocator(4))
axs[5].xaxis.set_minor_locator(ticker.MaxNLocator(40))

# Auto Locator
setup(axs[6], title="AutoLocator() MaxNLocatorと単純なデフォルト値")
axs[6].xaxis.set_major_locator(ticker.AutoLocator())
axs[6].xaxis.set_minor_locator(ticker.AutoMinorLocator())

# Log Locator
setup(axs[7], title="LogLocator(base=10, numticks=15) minからmaxまでの対数目盛")
axs[7].set_xlim(10**3, 10**10)
axs[7].set_xscale('log')
axs[7].xaxis.set_major_locator(ticker.LogLocator(base=10, numticks=15))

plt.savefig("tick-locators.png")

plt.tight_layout()
plt.show()

目盛フォーマット（Tick Formatters）の設定

tick-formatter1.png
tick-formatter2.png

# https://matplotlib.org/stable/gallery/ticks_and_spines/tick-formatters.html?highlight=tick%20formatを編集
import matplotlib.pyplot as plt
from matplotlib import ticker

#日本語fontの設定
from matplotlib import rcParams
rcParams['font.family'] = 'sans-serif'
rcParams['font.sans-serif'] = ['Meirio', 'Hiragino Maru Gothic Pro', 'Yu Gothic', 
                               'Takao', 'IPAexGothic', 'IPAPGothic', 
                               'VL PGothic', 'Noto Sans CJK JP']

def setup(ax, title):
    """Set up common parameters for the Axes in the example."""
    # only show the bottom spine
    ax.yaxis.set_major_locator(ticker.NullLocator())
    ax.spines['right'].set_color('none') #ver.3.4.1では、ax.spines.right.set_color('none')
    ax.spines['left'].set_color('none') #ver.3.4.1では、ax.spines.left.set_color('none')
    ax.spines['top'].set_color('none') #ver.3.4.1では、ax.spines.top.set_color('none')

    # define tick positions
    ax.xaxis.set_major_locator(ticker.MultipleLocator(1.00))
    ax.xaxis.set_minor_locator(ticker.MultipleLocator(0.25))

    ax.xaxis.set_ticks_position('bottom')
    ax.tick_params(which='major', width=1.00, length=5)
    ax.tick_params(which='minor', width=0.75, length=2.5, labelsize=10)
    ax.set_xlim(0, 5)
    ax.set_ylim(0, 1)
    ax.text(0.0, 0.2, title, transform=ax.transAxes,
            fontsize=14, color='tab:blue')


# Tick formatters can be set in one of two ways, either by passing a ``str``
# or function to `~.Axis.set_major_formatter` or `~.Axis.set_minor_formatter`,
# or by creating an instance of one of the various `~.ticker.Formatter` classes
# and providing that to `~.Axis.set_major_formatter` or
# `~.Axis.set_minor_formatter`.

# The first two examples directly pass a ``str`` or function.

fig0, axs0 = plt.subplots(2, 1, figsize=(8, 2))
fig0.suptitle('Simple Formatting')

# A ``str``, using format string function syntax, can be used directly as a
# formatter.  The variable ``x`` is the tick value and the variable ``pos`` is
# tick position.  This creates a StrMethodFormatter automatically.
setup(axs0[0], title="'{x} km'")
axs0[0].xaxis.set_major_formatter('{x} km')

# A function can also be used directly as a formatter. The function must take
# two arguments: ``x`` for the tick value and ``pos`` for the tick position,
# and must return a ``str``  This creates a FuncFormatter automatically.
setup(axs0[1], title="lambda x, pos: str(x-5)")
axs0[1].xaxis.set_major_formatter(lambda x, pos: str(x-5))

fig0.tight_layout()
plt.savefig("tick-formatter1.png", bbox_inches='tight', pad_inches=0.1)

# The remaining examples use Formatter objects.

fig1, axs1 = plt.subplots(7, 1, figsize=(8, 6))
fig1.suptitle('Formatter Object Formatting')

# Null formatter
setup(axs1[0], title="NullFormatter() 目盛を表示しない")
axs1[0].xaxis.set_major_formatter(ticker.NullFormatter())

# StrMethod formatter
setup(axs1[1], title="StrMethodFormatter('{x:.3f}') フォーマットを指定")
axs1[1].xaxis.set_major_formatter(ticker.StrMethodFormatter("{x:.3f}"))

# FuncFormatter can be used as a decorator
@ticker.FuncFormatter
def major_formatter(x, pos):
    return f'[{x:.2f}]'

setup(axs1[2], title='FuncFormatter("[{:.2f}]".format 表示するラベルを返すユーザ定義関数を使用')
axs1[2].xaxis.set_major_formatter(major_formatter)

# Fixed formatter
setup(axs1[3], title="FixedFormatter(['A', 'B', 'C', ...]) 指定したラベルを表示")
# FixedFormatter should only be used together with FixedLocator.
# Otherwise, one cannot be sure where the labels will end up.
positions = [0, 1, 2, 3, 4, 5]
labels = ['A', 'B', 'C', 'D', 'E', 'F']
axs1[3].xaxis.set_major_locator(ticker.FixedLocator(positions))
axs1[3].xaxis.set_major_formatter(ticker.FixedFormatter(labels))

# Scalar formatter
setup(axs1[4], title="ScalarFormatter() スカラー値（デフォルト）")
axs1[4].xaxis.set_major_formatter(ticker.ScalarFormatter(useMathText=True))

# FormatStr formatter
setup(axs1[5], title="FormatStrFormatter('#%d') 各ラベルに指定したらフォーマットの文字列を使用")
axs1[5].xaxis.set_major_formatter(ticker.FormatStrFormatter("#%d"))

# Percent formatter
setup(axs1[6], title="PercentFormatter(xmax=5) パーセント表示 (目盛の最大値/xmax)×100")
axs1[6].xaxis.set_major_formatter(ticker.PercentFormatter(xmax=5))

fig1.tight_layout()
plt.savefig("tick-formatter2.png", bbox_inches='tight', pad_inches=0.1)

#plt.show()

LineとMarkerのパターン

MarkerandLines.png

fig = plt.figure(figsize=(20,3))
ax = fig.add_subplot(111, xlim=(-1, 40), ylim=(0.05, 0.2), frameon=False, xticks=[], yticks=[])

# Lineをプロット
ls_list = ['-','--', ':', '-.']

for i, ls in enumerate(ls_list):
    text = "'%s'" % ls
    ax.text(10*i+4, 0.17, text, size=30, va='center')
    ax.plot([10*i+2, 10*i+7], [0.15, 0.15], ls, color='black', linewidth=2)
ax.text(-1, 0.16, 'Lines', size=20, ha='left');

# Markerをプロット
m_list = ['.', ',', 'o', 'v', '^', '<', '>', '1', '2', '3', '4', '8', 's',
          'p', '*', 'h', 'H', '+', 'P', 'x', 'X', 'D', 'd', '|', '_',
          0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, '']

for i, m in enumerate(m_list):
    ax.plot(i+3, 0.1, c='gainsboro',
            marker=m, ms=15, mfc='lightsteelblue', mew=1.5, mec='royalblue')
    ax.text(i+3, 0.12, m, size=20, ha='center')
ax.text(-1, 0.12, 'Markers', size=20, ha='left')

fig.savefig('MarkerandLines.png')

シンプルなプロット(パターン1)

import matplotlib as mpl
import matplotlib.pyplot as plt
from matplotlib.ticker import AutoMinorLocator, MultipleLocator
import numpy as np

#日本語fontの設定
from matplotlib import rcParams
rcParams['font.family'] = 'sans-serif'
rcParams['font.sans-serif'] = ['Meirio', 'Hiragino Maru Gothic Pro', 'Yu Gothic', 
                               'Takao', 'IPAexGothic', 'IPAPGothic', 
                               'VL PGothic', 'Noto Sans CJK JP']
%matplotlib inline


# データの作成
x = np.linspace(0, 20, 1000)
y1 = 0.8 * np.sin(x)
y2 = 0.8 * np.cos(x)


# 作図パラメータの設定
figsize = (10, 5)  #図のプロットサイズ
hspace, wspace = 0.4, 0.4  #プロットの間隔(サブプロットの幅と高さに対する比率(0.2→20%))

xmin, xmax, dx = 0, 20, 1.0 # lower limit, upper limit and increment of of axis
ymin, ymax, dy = -1, 1, 0.2 

nAutoMinorLoc_x, nAutoMinorLoc_y = 4, 4  # Number of AutoMinorLocator

title = 'Fig. Sample1'
xlabel, ylabel = 'x軸 [単位]', 'y axis [Unit]'


# 作図
fig = plt.figure(figsize=figsize)
fig.subplots_adjust(hspace=hspace, wspace=wspace)

ax = fig.add_subplot(1, 1, 1)
ax.plot(x, y1, linewidth=2, color='royalblue', label="sin x")
ax.plot(x, y2, '--', linewidth=1, color='orangered', label="cos x")
ax.plot(x[100], y1[100], 'o', markersize=10, markeredgecolor='navy', 
        markeredgewidth=2.0, markerfacecolor='0.8', label='')

# 図のタイトル
ax.set_title(title, fontsize=20)

# 軸の設定
ax.set(xlim=(xmin, xmax), ylim=(ymin, ymax))

ax.set_xlabel(xlabel, fontsize=12)
ax.set_ylabel(ylabel, fontsize=12)

ax.xaxis.set_major_locator(MultipleLocator(dx)) #指定した数の倍数に主目盛りが設定される
ax.xaxis.set_minor_locator(AutoMinorLocator(nAutoMinorLoc_x))
ax.yaxis.set_major_locator(MultipleLocator(dy))
ax.yaxis.set_minor_locator(AutoMinorLocator(nAutoMinorLoc_y))

ax.tick_params(which='both', direction='in', width=1.0, labelsize=12, labelcolor='black')
ax.tick_params(which='major', length=6)
ax.tick_params(which='minor', length=3);

ax.grid(which='major', axis='both', linestyle="-", linewidth=0.5, color='0.5') #, zorder=-10

# y=0のラインの追加
ax.axhline(0, 0, 1, linestyle="-", linewidth=1, color='black')


# 凡例の設定
ax.legend(bbox_to_anchor=(1.01, 1), loc='upper left', borderaxespad=0, fontsize=12)

# 図の出力
fig.savefig("case1.jpg", bbox_inches='tight', pad_inches=0.1, dpi=200);

case1.jpg

以下、更新中

5
4
0

Register as a new user and use Qiita more conveniently

  1. You get articles that match your needs
  2. You can efficiently read back useful information
  3. You can use dark theme
What you can do with signing up
Sign upLogin
5
4