Question

我有日期列表，我想在python中生成带有matplotlib的条形图。

我想提供这两种类型的条形码

我可以使用此代码，但我正在寻找更有效的代码，因为您可以看到我在2007年到2012年之间有多年，有时候这个范围会更宽

def plot():
    #--- the two samples ---
    samples1 = [1, 1, 1, 3, 2, 5, 1, 10, 10, 8]
    samples2 = [6, 6, 6, 1, 2, 3, 9, 12 ] 
    samples3 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 11, 12]

    N = 12 # number of bins
    hist1 = np.array([0] * N )
    hist2 = np.array([0] * N )
    hist3 = np.array([0] * N )

    #--- create two histogram. Values of 1 go in Bin 0 ---
    for x in samples1:
        hist1[x-1] += 1
    for x in samples2:
        hist2[x-1] += 1
    for x in samples3:
        hist3[x-1] += 1

    #--- display the bar-graph ---        
    width = 1
    p1 = plt.bar( np.arange(0,N)+0.5, hist1, width, color='#9932cc' )
    p2 = plt.bar( np.arange(0,N)+0.5, hist2, width, color='#ffa500', bottom=hist1 )
    p3 = plt.bar( np.arange(0,N)+0.5, hist3, width, color='#d2691e', bottom=hist1+hist2 )
    plt.legend( (p1[0], p2[0], p3[0]), ( 'hist1', 'hist2', 'hist3' ) )
    plt.xlabel( 'Bins' )
    plt.ylabel( 'Count' )
    #plt.axis([1, 46, 0, 6])
    plt.xticks( np.arange( 1,N+1 ) )
    plt.axis( [width/2.0, N+width/2.0, 0, max( hist1+hist2+hist3)] )
    plt.show()

你能帮我生成这种图表吗？

谢谢

Answer 1

您可以使用numpy histogram直接获取条形格式的数据，这应该比在python中循环更快。作为基于上述数据的最小示例，

import numpy as np
import matplotlib.pyplot as plt

#--- the two samples ---
samples1 = [1, 1, 1, 3, 2, 5, 1, 10, 10, 8]
samples2 = [6, 6, 6, 1, 2, 3, 9, 12 ] 
samples3 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 11, 12]

N = 12 # number of bins
hist1 = np.array([0] * N )
hist2 = np.array([0] * N )
hist3 = np.array([0] * N )

#--- create two histogram. Values of 1 go in Bin 0 ---
hist1, n = np.histogram(samples1,N)
hist2, n = np.histogram(samples2,N)
hist3, n = np.histogram(samples3,N)

#--- display the bar-graph ---        
width = 1
p1 = plt.bar( np.arange(0,N)+0.5, hist1, width, color='#9932cc' )
p2 = plt.bar( np.arange(0,N)+0.5, hist2, width, color='#ffa500', bottom=hist1 )
p3 = plt.bar( np.arange(0,N)+0.5, hist3, width, color='#d2691e', bottom=hist1+hist2 )
plt.legend( (p1[0], p2[0], p3[0]), ( '2010', '2011', '2012' ) )
plt.xlabel( 'Bins' )
plt.ylabel( 'Count' )
import datetime
months = [((datetime.date(2010, i, 1).strftime('%B'))[:3]) for i in range(1,13)]
plt.xticks( np.arange( 1,N+1 ),months )
plt.axis( [width/2.0, N+width/2.0, 0, max( hist1+hist2+hist3)] )
plt.show()

Answer 2

这两个图以非常相似的方式生成，所以我将只做第一个。您需要循环几个月，并获得一个堆积条形图，将每个月的条形bottom设置为每年前几个月的累计值：

import numpy as np
import matplotlib.pyplot as plt

months = ('Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
          'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec')

# Some random data for nyears from minyear
nyears = 8
nmonths = len(months)
minyear = 2005
monthly_counts = np.random.randint(low=2, high=15, size=(nyears,nmonths))

fig, ax = plt.subplots()
ind = np.arange(nyears)
width = 0.45
# Random colors for the months
c = np.random.rand(nmonths,3,1)

p = []
for imonth in range(nmonths):
    p.append(ax.bar(ind, monthly_counts[:,imonth], width,
                    bottom=np.sum(monthly_counts[:,:imonth], axis=1),
                    color=c[imonth], alpha=0.8)
            )

# Set x axis ticks and labels
ax.set_xticks(ind + width/2)
ax.set_xticklabels([str(minyear+i) for i in ind])

# Locate legend outside axes plot area
box = ax.get_position()
ax.set_position([box.x0, box.y0, box.width * 0.8, box.height])
ax.legend([pl[0] for pl in p], months, loc='center left', bbox_to_anchor=(1, 0.5))

plt.show()

如何在matplotlib python中生成每年出现的条形图？

2 个答案: