我有一个巨大的文件,其中有一些丢失的行。数据需要植根于国家。
输入数据如下:
csv_str = """Type,Country,State,County,City,
1,USA,,,
2,USA,OH,,
3,USA,OH,Franklin,
4,USA,OH,Franklin,Columbus
4,USA,OH,Franklin,Springfield
4,USA,WI,Dane,Madison
"""
需要:
csv_str = """Type,Country,State,County,City,
1,USA,,,
2,USA,OH,,
3,USA,OH,Franklin,
4,USA,OH,Franklin,Columbus
4,USA,OH,Franklin,Springfield
4,USA,WI,,
4,USA,WI,Dane,
4,USA,WI,Dane,Madison
"""
根据我的逻辑关键字是Type
字段,如果我找不到城市(类型4)的县(类型3),则插入一个字段到县的行。
与县相同。如果我找不到县(类型3)的州(类型2),则插入一行,其中字段最多为州。
由于我对python中的设施缺乏了解,我正在尝试更多的蛮力方法。这有点问题,因为我需要在同一个文件上进行大量迭代。
我也尝试了谷歌精炼,但无法让它工作。手动操作非常容易出错。
任何帮助表示感谢。
import csv
import io
csv_str = """Type,Country,State,County,City,
1,USA,,,
2,USA,OH,,
3,USA,OH,Franklin,
4,USA,OH,Franklin,Columbus
4,USA,OH,Franklin,Springfield
4,USA,WI,Dane,Madison
"""
found_county =[]
missing_county =[]
def check_missing_county(row):
found = False
for elm in found_county:
if elm.Type == row.Type:
found = True
if not found:
missing_county.append(row)
print(row)
reader = csv.reader(io.StringIO(csv_str))
for row in reader:
check_missing_county(row)
答案 0 :(得分:1)
根据我对这个问题的理解,我已经敲了下面的内容:
import csv
import io
csv_str = u"""Type,Country,State,County,City,
1,USA,,,
2,USA,OH,,
3,USA,OH,Franklin,
4,USA,OH,Franklin,Columbus
4,USA,OH,Franklin,Springfield
4,USA,WI,Dane,Madison
"""
counties = []
states = []
def handle_missing_data(row):
try:
rtype = int(row[0])
except ValueError:
return []
rtype = row[0]
country = row[1]
state = row[2]
county = row[3]
rows = []
# if a state is present and it hasn't a row of it's own
if state and state not in states:
rows.append([rtype, country, state, '', ''])
states.append(state)
# if a county is present and it hasn't a row of it's own
if county and county not in counties:
rows.append([rtype, country, state, county, ''])
counties.append(county)
# if the row hasn't already been added add it now
if row not in rows:
rows.append(row)
return rows
csvf = io.StringIO(csv_str)
reader = csv.reader(csvf)
for row in reader:
new_rows = handle_missing_data(row)
for new_row in new_rows:
print new_row