AssertionError：不兼容的尺寸：參數'高度'必須是長度5或標量

Question

我有一個json文件，我正在反向排序使用natsort，然後我想繪製一個「速度」的圖形，但我得到一個錯誤。我現在在這裏也包含了JSON文件。

"AssertionError: incompatible sizes: argument 'height' must be length 5 or scalar" 

Traceback (most recent call last): File "new.py", line 71, in <module> visualize_type(sorted_waypoints) File "new.py", line 45, in visualize_type plt.bar(xlocations, counter.values()) File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/matp‌​lotlib/pyplot.py", line 2515, in bar ret = ax.bar(left, height, width=width, bottom=bottom, **kwargs) File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/matp‌​lotlib/axes.py", line 4999, in bar nbars) 

代碼：

import json 
import datetime 
import pprint 
from operator import itemgetter 
import natsort 
import matplotlib.pyplot as plt 
import numpy as np 
from collections import Counter 



#path to gps data file in json format. 
data_file = "waypoints.json" 


def speed_ans(self, data_file): 
    pass 



def visualize_type(output): 
    """Visualize data by category in a bar graph""" 

    #This returns a dict where it sums the total per Category. 
    counter = Counter(item["Speed"] for item in output) 

    # Set the labels which are based on the keys of our counter. 
    labels = tuple("Speed") 

    # Set where the labels hit the x-axis 
    xlocations = np.arange(len(labels)) + 0.5 

    # Width of each bar 
    width = 0.5 

    # Assign data to a bar plot 
    plt.bar(xlocations, counter.values(), width=width) 

    # Assign labels and tick location to x- and y-axis 
    plt.xticks(xlocations + width/2, labels, rotation=90) 
    plt.yticks(range(0, max(counter.values()), 5)) 

    # Give some more room so the labels aren't cut off in the graph 
    plt.subplots_adjust(bottom=0.4) 

    # Make the overall graph/figure larger 
    plt.rcParams['figure.figsize'] = 12, 8 

    # Save the graph! 
    plt.savefig("Graph.png") 

    plt.clf() 



if __name__ == '__main__': 
    with open(data_file) as f: 
     waypoints = json.load(f) 

    sorted_waypoints = natsort.natsorted(waypoints, key=itemgetter(*['Speed']), reverse = True) 
    pprint.pprint(sorted_waypoints) 

    visualize_type(sorted_waypoints) 

waypoints.json文件：

[{ 
    "Latitude": 1.282143333, 
    "Timestamp": 1434368770, 
    "Speed": 7.696, 
    "Longitude": 103.850785 
}, { 
    "Latitude": 1.282205, 
    "Timestamp": 1434368771, 
    "Speed": 7.233, 
    "Longitude": 103.850806667 
}, { 
    "Latitude": 1.282205, 
    "Timestamp": 1434368772, 
    "Speed": 7.233, 
    "Longitude": 103.850806667 
}, { 
    "Latitude": 1.282205, 
    "Timestamp": 1434368773, 
    "Speed": 7.444, 
    "Longitude": 103.850806667 
}, { 
    "Latitude": 1.282261667, 
    "Timestamp": 1434368774, 
    "Speed": 6.933, 
    "Longitude": 103.850833333 
}] 

Answer 1

我想你做什麼tuple()確實爲字符串的不正確的假設：

tuple("Speed") 
# returns ('S', 'p', 'e', 'e', 'd') 

我想你想要：

labels = counter.keys()