CSV字段导入格式问题

Question

我正在尝试使用Google Maps JavaScript API v3中的热图可视化服务。

我有一个带lat，lng和weight的csv文件。它看起来像这样：

lat,    lng,    weight
37.782551, -122.445368, 1
51.520027,  -0.0923842, 2

我希望从这些csv值得到以下结果 -

{location: new google.maps.LatLng(37.782551,-122.445368), weight: 1},
{location: new google.maps.LatLng(51.520027,-0.0923842), weight: 2},

我不懂JavaScript，所以我尝试使用Python。

with open('./Test.csv', 'rU') as csvfile:
    reader = csv.DictReader(csvfile)
    location = ['{lat},{lng}'.format(**row) for row in reader]
    weight = ['weight'.format(**row) for row in reader]

for i in range(0,(len(location))):
    location_lt = ("new google.mapsLatLng", location[i])
    location_we = (location_lt, "weight", weight)
    print(location_we)

然而，这有很多问题。重量场缺失。我相信我应该尝试使用zip功能。格式也不如上所述

(('new google.mapsLatLng', '51.5195078,-0.0971911'), 'weight', [])
(('new google.mapsLatLng', '51.520027,-0.0923842'), 'weight', [])

任何指针都会非常感激。

Answer 1

正如你的问题所说，让我们认真考虑你想要一个字符串作为位置。那么真正的潜在问题很简单，你将如何转换你的CSV文件？您将以相同的方式转换每一行，因此您应该为此创建一个函数。例如：

import csv

fmt01 = "new google.mapsLatLng({lat},{lng})"
def row_transform01(row):
  lat = row["lat"]
  lng = row["lng"]
  weight = int(row["weight"])
  return dict(location=fmt01.format(lat=lat,lng=lng)
             ,weight=weight
             )

def transform(csvfilename, row_transform):
  with open(csvfilename, 'rU') as csvfile:
    reader = csv.DictReader(csvfile)
    transform = list(row_transform(row) for row in reader)
  return transform

for row in transform("/temp/temp.csv",row_transform01):
  print row

修改

好的，似乎你想要str我认为你想要dict。没有汗，只需改变行变换。

fmt02 = "{{location: new google.maps.LatLng({lat},{lng}), weight:{weight}}},"
def row_transform02(row):
  lat = row["lat"]
  lng = row["lng"]
  weight = int(row["weight"])
  return fmt02.format(lat=lat,lng=lng, weight=weight)

for row in transform("/temp/temp.csv",row_transform02):
  print row

Answer 2

这是我的解决方案 - 它提供了一个完全符合您要求的字符串 - 除了最后一行没有最终的逗号，因为它似乎是不可取的。

类似于其他答案的概念，你想要转换每一行，除了我在这里直接使用字符串格式来产生结果。

import csv

class CsvImport():
    resultFormat = "{{location: new google.maps.LatLng({lat},{lng}), weight: {weight}}}"

    def Run(self, filename):
        # Get the formatted rows from CSV file
        rows = self.readCsv(filename)
        print ",\n".join(rows)

    def readCsv(self, fileName):
        with open(fileName, 'rU') as csvfile:
            reader = csv.DictReader(csvfile)
            # Keys may or may not be pulled in with extra space by DictReader()
            # The next line simply creates a small dict of stripped keys to original padded keys
            keys = { key.strip(): key for (key) in reader.fieldnames }
            # Format each row into the final string
            rows = [ self.makeRow(row, keys) for row in reader ]
            return rows;

    def makeRow(self, row, keys):
        # Account for extra spaces in keys
        return self.resultFormat.format(
            lat=row[keys["lat"]].strip(), 
            lng = row[keys["lng"]].strip(), 
            weight=row[keys["weight"]].strip()
        )

if __name__ == "__main__":
    CsvImport().Run("./Test.csv")

结果：