[python] python 用 matplotlib 畫出散點圖 scatter 筆記, 標記上點的text

matplotlib  提供能畫的種類

http://matplotlib.org/gallery.html

source code example included.


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import matplotlib.pyplot as plt
import numpy as np

#find max under list of list, sublist[x] means the target column
def max_value_lol(inputlist,target_column):
    return max([sublist[target_column] for sublist in inputlist])

#畫出上下兩個圖根據不同data欄位, data is list of list , head_title is list for title
def data_Visualization(head_title,data):
    #print(max_value((data)))
    max_submit_times=max_value_lol(data,1)
    point_scale=6
    #print(len(data))

    fig=plt.figure(figsize=(6,4))
    ax=fig.add_subplot(211)
    N = len(data)
    for item in data :
        x = float(item[6])
        y = float(item[7])
        colors = np.random.rand(N)
        area = np.pi * (15 * (x+y)/2)**2
        #add wording besides the points
        ax.text(x, y, item[0])
        #area = np.pi * (15 * (item[1]/max_submit_times)*point_scale)**2  # 0 to 15 point radiuses
        plt.scatter(x, y, s=area, c=colors, alpha=0.5)

    plt.xlabel(head_title[6])
    plt.ylabel(head_title[7])
    plt.xlim(-0.2,float (max_value_lol(data,6))+0.2)
    plt.ylim(-0.2,float (max_value_lol(data,7))+0.2)
    #plt.legend()




    #second pic
    ax=fig.add_subplot(212)
    for item in data :
        x = float(item[8])
        y = float(item[9])
        colors = np.random.rand(N)
        area = np.pi * (15 * (float(item[8])+float(item[9]))/15)**2
        #area = np.pi * (15 * (item[1]/max_submit_times)*point_scale)**2  # 0 to 15 point radiuses
        plt.scatter(x, y, s=area, c=colors, alpha=0.5)


    plt.xlabel(head_title[8])
    plt.ylabel(head_title[9])
    plt.xlim(-0.2,float (max_value_lol(data,8))+1)
    plt.ylim(-0.2,float (max_value_lol(data,9))+5)

    plt.show()
    return


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