matplotlib 柱状图

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# coding utf-8

# import matplotlib
import numpy as np
import matplotlib.pyplot as plt
import matplotlib
import xlrd


def read_excel(path):
    try:
        list = []
        file = xlrd.open_workbook(path)
        sheet = file.sheet_by_index(0)
        rows = sheet.row_values
        for line in range(0, sheet.nrows):
            list.append(rows(line))
        return list
    except:
        pass


def fun1():
#    population = read_excel(r'renkou2016.xlsx')     # 人口列表
　　 population=[['年末总人口(万人)', 138271.0], ['0-14岁人口(万人)', 23091.0], ['15-64岁人口(万人)', 100246.0], ['65岁及以上人口(万人)', 14933.0]]#测试数据
    date = []
    name = []
    for i in range(0,len(population)):
        date.append(population[i][1])
        name.append(population[i][0])

    # 中文乱码的处理
    plt.rcParams['font.sans-serif'] = ['SimHei']  # 步骤一（替换sans-serif字体）
    plt.rcParams['axes.unicode_minus'] = False  # 步骤二（解决坐标轴负数的负号显示问题）

    # 绘图
    plt.bar(range(4), date, align = 'center',color='steelblue', alpha = 0.8)

    # 添加轴标签
    plt.ylabel('人口')   # 添加标题
    plt.title('2016年人口各年龄阶段分布的柱形图')    # 添加刻度标签
    plt.xticks(range(len(date)), name)
    # 设置Y轴的刻度范围
    plt.ylim([5000,150000])
    # 为每个条形图添加数值标签
    for x, y in enumerate(date):
        plt.text(x, y+100, '%s' % round(y, 1), ha='center')      # 显示图形 plt.show()
    return plt


if __name__ == '__main__':
    plt = fun1()
    plt.show()