Question

我只是试图从pandas DataFrame中列出地区名称和District对象的列表，但是由于某些原因，代码永远无法完成运行。我看不到任何可能成为无限循环的地方，因此，为什么每次运行它都会卡住，这超出了我的范围。这是卡住的部分（尤其是j迭代的for循环）：

import numpy as np
import pandas as pd

#make dataframe
data = pd.read_csv('gun-violence-data_01-2013_03-2018.csv', header=0, delimiter=',')

#drop data points with null condressional district values
data = data[data.congressional_district != 0]
data.dropna(axis=0,how='any',subset=['congressional_district'],inplace= True)

#constructing working table
table = data[['incident_id','state','congressional_district']]

#list of districts. Formatting in original file must be corrected to analyze data
districtNames = ['filler1','filler2']
districts = []
s = table.shape

#loop thru the rows of the table
for i in range(s[0]):
    check = True

    #build strings for each district
    ds = table.iloc[i,1] + str(table.iloc[i,2])
    #testString = str(table.iloc[i,2])

    #append ds to districtNames if it isnt in already
    #make array of District Objects
    for j in range(len(districtNames)):
        if(ds == districtNames[j]):
            check = False
        if(check):
            districtNames.append(ds)
            districts.append(District(ds,0))

作为参考，这是地区类：

class District:
def __init__(self, name, count):
    self._name = name
    self._count = count
def get_name(self):
    return name
def get_count(self):
    return count
def updateCount(self,amount):
    self._count += amount

.csv初始文件很大，在切掉第8行和第9行中的某些数据点后，我还剩下227,312个数据点。我了解这很多，但是运行5分钟后代码甚至还没有完成。我在做什么错了？

Answer 1

并不是它不会终止，而是在当前状态下效率低下。尝试这样的事情：

import numpy as np
import pandas as pd

class District:
    def __init__(self, name, count):
        self._name = name
        self._count = count
    def get_name(self):
        return name
    def get_count(self):
        return count
    def updateCount(self,amount):
        self._count += amount

#make dataframe
data = pd.read_csv('gun-violence-data_01-2013_03-2018.csv', header=0, delimiter=',')

#drop data points with null condressional district values
data = data[data.congressional_district != 0]
data.dropna(axis=0,how='any',subset=['congressional_district'],inplace= True)

#constructing working table
table = data[['incident_id','state','congressional_district']]

#list of districts. Formatting in original file must be corrected to analyze data
districtNames = (table.state + table.congressional_district.astype(str)).unique()
districts = list(map(lambda districtName: District(districtName, 0), districtNames))

Answer 2

您可以使用<div class="green"> <span>Green</span> </div> <div class="blue"> <span>Blue</span> </div>包来查看代码在哪个循环中停留。

tqdm

陷入潜在的无限循环

2 个答案: