习题1:读入文件pmi_days.csv,完成以下操作:
1.统计质量等级对应的天数,例如:
优:5天
良:3天
中度污染:2天
2.找出PMI2.5的最大值和最小值,分别指出是哪一天。
#习题1:读入文件pmi_days.csv,完成以下操作:
#1.统计质量等级对应的天数,例如:
#优:5天
#良:3天
#中度污染:2天
#2.找出PMI2.5的最大值和最小值,分别指出是哪一天。
import csv
filename='D:\Downloads\pmi_days.csv'
with open(filename, 'r') as f:
reader = csv.reader(f)
header_row = next(reader)
heads = []# 创建一个空列表用于存放每天的质量等级
pm=[]#创建一个空列表用于存放每天的PM2.5
day=[]#创建一个空列表用于存放日期
for row in reader: # 遍历文件对象
heads.append(row[2]) # 添加每行的第一列到列表里
pm.append(int(row[3]))
day.append(row[0])
y=0
l=0
q=0
z=0
for i in range (30):
if heads[i]=="优":
y=y+1
elif heads[i]=="良":
l=l+1
elif heads[i]=='轻度污染':
q=q+1
elif heads[i]=='中度污染':
z=z+1
zuida=max(pm)
zuixiao=min(pm)
print("优{}天,良{}天,轻度污染{}天,中度污染{}天".format(y,l,q,z))
for a in range(30):
if pm[a]==zuida:
print("PMI2.5的最大值是{},是{}".format(zuida,day[a]))
for b in range(30):
if pm[b]==zuixiao:
print("PMI2.5的最小值是{},是{}".format(zuixiao, day[b]))
习题2:读入文件1980-2018GDP.csv,完成以下操作:
1.按行输出每年GDP数据,表头列名如文件第1行所示。
import csv with open("D:\Downloads\GDP.csv" ,'r') as f: reader = csv.reader(f) #默认返回list 每行类型 for row in reader: print(row)
2.将各年GDP数据转换成字典格式,以年份为keys,其它值为values(数据类型为列表方式),例如:
{
2017:[827121.7,6.8%,60989]
........
}
import csv
list=[]
list1=[]
zidian={}
daxiao=[]
d=0
e=0
with open("D:\Downloads\GDP.csv",'r') as f:
reader = csv.reader(f)
fieldnames = next(reader)
print(fieldnames)
csv_reader = csv.DictReader(f,fieldnames=fieldnames)
for row in reader:
list.append(row)
for i in range(0,len(list)):
print("%-8s"%list[i][0],"\t%-10.7s"%list[i][1],"\t%-12.5s"%list[i][2],"\t%-13.5s"%list[i][3],list[i][4])
with open("D:\Downloads\GDP.csv", 'r') as f:
reader = csv.reader(f)
fieldnames = next(reader)
csv_reader = csv.DictReader(f, fieldnames=fieldnames)
for row in csv_reader:
dict={}
for key,value in row.items():
dict[key] = value
if key == 'GDP(亿元)':
daxiao.append(float(dict.get('GDP(亿元)')))
dict.get('年份')
list1.append(int(dict.get('年份')))
for i in range(0, len(list)):
zidian[list1[i]] = list[i][1:]
print(zidian)
for i in range(0,len(daxiao)):
if daxiao[i]==max(daxiao):
d=list1[i]
if daxiao[i]==min(daxiao):
e=list1[i]
print("PM2.5最大值:{} 日期:{}".format(max(daxiao), d))
print("PM2.5最小值:{} 日期:{}".format(min(daxiao), e))