【python實(shí)戰(zhàn)】matplotlib繪圖（三）

今天主要講一下get到的一些小技能刷钢，包括：

當(dāng)坐標(biāo)軸標(biāo)簽太長串绩，出框的時(shí)候室琢，自動(dòng)調(diào)整子圖——語句：plt.tight_layout()
自動(dòng)調(diào)整text（文本標(biāo)簽）的位置遮糖，避免重疊——調(diào)包：adjustText（具體文檔見adjustText文檔）
調(diào)用已有的顏色主題麻汰；Choosing Colormaps in Matplotlib

import matplotlib.pyplot as plt
import matplotlib
import numpy as np
import matplotlib.transforms as mtransforms
from matplotlib.ticker import FuncFormatter
from adjustText import adjust_text
from matplotlib import cm
#設(shè)置字體速客、圖形樣式
matplotlib.rcParams['font.sans-serif'] = ['SimHei']
matplotlib.rcParams['font.family']='sans-serif'
matplotlib.rcParams['axes.unicode_minus'] = False
# 顏色轉(zhuǎn)換
def RGB_to_Hex(tmp):
    rgb = tmp.split(',')#將RGB格式劃分開來
    strs = '#'
    for i in rgb:
        num = int(i)#將str轉(zhuǎn)int
        #將R、G五鲫、B分別轉(zhuǎn)化為16進(jìn)制拼接轉(zhuǎn)換并大寫
        strs += str(hex(num))[-2:].replace('x','0').upper()
    return strs

1.左右條形圖（left_right_barh)

left_right_barh.png

def left_right_barh(fig,subplotid,ylabel,values1,values2,label1,label2,textformat,withlegend=1,category=0,filename=0):
    values1=[0-i for i in values1]
    # 倒序
    ylabel,values1,values2=ylabel[::-1],values1[::-1],values2[::-1]
    # 作圖
    ax=fig.add_subplot(subplotid)
    barh1=ax.barh(ylabel,width=values1,label=label1)
    barh2=ax.barh(ylabel,width=values2,label=label2)
    # 去掉邊框
    orientation=['top','bottom','right']
    for o in orientation:
        ax.spines[o].set_visible(False)
    # 去掉xticks
    ax.set_xticks(())
    # 圖例
    if withlegend:
        ax.legend(ncol=2, bbox_to_anchor=(0.5, -0.1),edgecolor='w',
                      loc='lower center', fontsize='small')
    # y軸標(biāo)題
    if category:
        ax.set_ylabel(category)
    # 添加barh的數(shù)據(jù)標(biāo)簽
    texts=[]
    for b in barh1:
        texts.append(ax.text(b.get_width()-0.04,b.get_y()+b.get_height()/3,
            format(-b.get_width(),textformat),va="center",ha='left'))
    for b in barh2:
        texts.append(ax.text(b.get_width(),b.get_y()+b.get_height()/3,
            format(b.get_width(),textformat),va="center",ha='right'))
    adjust_text(texts,only_move={'points':'x', 'text':'x', 'objects':'x'}) #避免y軸上的調(diào)整
    plt.tight_layout()#調(diào)整子圖溺职，避免標(biāo)簽出框，自動(dòng)調(diào)整的語句,圖則會(huì)自動(dòng)調(diào)整標(biāo)簽大小
    if filename:
        plt.savefig(filename,dpi=600)
    return ax
def left_right_barh_ex():
    # 數(shù)據(jù)
    ylabel=["不識(shí)字或識(shí)字很少","小學(xué)","初中","普通高中","中等職業(yè)/技術(shù)/師范學(xué)校","高職/大專","本科","研究生","博士"]
    values1=[0.0477,0.2013,0.2751,0.128,0.0774,0.1219,0.1244,0.0172,0.007]
    values2=[0.0196,0.1405,0.2834,0.1577,0.0597,0.1275,0.1698,0.0299,0.0119]
    textformat='.2%'
    fig=plt.figure()
    left_right_barh(fig,111,ylabel=ylabel,values1=values1,values2=values2,
        label1='母親',label2='父親',filename="left_right_barh.png",textformat=textformat)
    plt.show()
left_right_barh_ex()

若不加plt.tight_layout()的效果如下位喂，可以看到辅愿，縱坐標(biāo)標(biāo)簽太長已經(jīng)出去了。

left_right_barh（軸標(biāo)簽未調(diào)整）.png

若不加adjust_text(texts,only_move={'points':'x', 'text':'x', 'objects':'x'})的效果如下忆某，可以看到点待，數(shù)據(jù)標(biāo)簽擠在一起了。

left_right_barh（數(shù)據(jù)標(biāo)簽未調(diào)整）.png

adjustText這個(gè)包在做散點(diǎn)圖進(jìn)行數(shù)據(jù)標(biāo)簽添加時(shí)弃舒，應(yīng)該是最有用的癞埠，文檔中的例子如下：

adjustText.png

2.簡單柱狀圖（simple_bar)

simple_bar1.png

def simple_bar(xlabel,value,colorname,filename):
    # 系列顏色選取
    colorname=cm.get_cmap(name=colorname)
    color=colorname(value)
    fig=plt.figure()
    ax=fig.add_subplot()
    bar=ax.bar(xlabel,value,color=color)
    # 去掉邊框
    orientation=['top','left','right']
    for o in orientation:
        ax.spines[o].set_visible(False)
    # 去掉xticks
    ax.set_yticks(())
    # 文本標(biāo)簽
    for b in bar:
        ax.text(b.get_x()+b.get_width()/2,b.get_height()+0.01,
            format(b.get_height(),'.2%'),va="center",ha='center')
    plt.savefig(filename,dpi=600)
    plt.show()
def simple_bar_ex1():
    xlabel=["5萬元以下",    "5萬-10萬",   "11萬-20萬",  "21萬-40萬",  "41萬以上"]
    value=[0.3417,  0.3095, 0.2272, 0.0858, 0.0359]
    simple_bar(xlabel,value,colorname='coolwarm',filename='simple_bar1.png')

這里用的colorname是”coolwarm”状原，改一下這個(gè)colorname為“Pastel1”，效果如下：