Question

现在，我正在一个项目中，尝试可视化纽约市的互联网覆盖范围。我已经下载了fcc的csv，其中详细介绍了美国的互联网覆盖范围，并使用java对其进行了解析，以获取仅与纽约有关的所有数据。我仅通过选择包含纽约5个县（五个行政区）的正确普查代码的数据行来做到这一点。这是问题所在。 fcc的csv仅有的地理链接数据是人口普查代码，现在，我在将数据链接到地图上的地理位置时遇到了麻烦。我有一个geojson文件，其中包含与nyc中每个人口普查代码一起提供的地理数据，但是我不知道如何在Java中解析和编辑geojson文件。这是我拥有的geojson的格式：

{
   "type": "FeatureCollection",
   "features": [
      {
         "type": "Feature",
         "id": 0,
         "properties": {
            "OBJECTID": 2038,
            "STATEFP": "36",
            "COUNTYFP": "081",
            "TRACTCE": "014000",
            "BLKGRPCE": "1",
            "GEOID": "360810140001",
            "NAMELSAD": "Block Group 1",
            "MTFCC": "G5030",
            "FUNCSTAT": "S",
            "ALAND": 113131,
            "AWATER": 0,
            "INTPTLAT": "+40.7030341",
            "INTPTLON": "-073.8279064",
            "geo_id": "15000US360810140001",
            "OBJECTID_1": 10466,
            "GEOID_1": "15000US360810140001",
            "SHAPE_Leng": 0.02086447918,
            "SHAPE_Area": 0.00001205464
         },
         "geometry": {
            "type": "Polygon",
            "coordinates": [
               [
                  [
                     -73.82266,
                     40.703585
                  ],
                  [
                     -73.83152,
                     40.70139
                  ],
                  [
                     -73.83213,
                     40.702794
                  ],
                  [
                     -73.82576,
                     40.704428
                  ],
                  [
                     -73.82246,
                     40.703656
                  ],
                  [
                     -73.82266,
                     40.703585
                  ]
               ]
            ]
         }
      },

我想象的方法是选择第一个geojson对象，然后使用该代码搜索csv，或者选择第一个csv行，然后在我的geojson中搜索相同的普查代码。这样显然是效率低下的。是一种更好的解决方案，以某种方式根据普查代码的数值对csv进行排序，然后从geojson开始读取吗？如果csv被订购，我可以编写一个二进制搜索算法来做到这一点。

总结一下：我需要基于一列的数值排序csv的帮助，以及有关读取和编辑geojson文件的帮助。我将不胜感激。

这是我试图用来配对值的代码（我已经将geojson转换为csv，但是我发现当从csv转换为geojson时，我发现没有在线代码可以正常工作。

public static void main(String args[]) throws FileNotFoundException{
  // Construct a BufferedReader object from the input file
    BufferedReader r = new BufferedReader(new FileReader("newyorkcitydistilled.csv"));
    BufferedReader cs = new BufferedReader(new FileReader("convertcsv.csv"));
    String[] linedata;
    String[] linedata2;
    PrintWriter pw = new PrintWriter(new File("nycdistilledgeo2.csv"));
    String line;
    String line2;
    int it = 0;
  try{
//prime the geodata

//NOTE TO SELF!!! THE CSV FOR CONVERT NEETS TO BE REFORMATTED BECAUSE OF THE FIRST THREE COLUMNS
      line2 = cs.readLine();
      linedata2 = line2.split(",(?=(?:[^\"]*\"[^\"]*\")*[^\"]*$)", -1);

    while ((line = r.readLine()) != null) {
          if (line.isEmpty()) {
              break;}
          it++;
          if(it % 100 == 0)
          System.out.println(it);
          linedata = line.split(",(?=(?:[^\"]*\"[^\"]*\")*[^\"]*$)", -1);
      //    System.out.print(line2);
//while the two lines being looked at dont fit the matching criteria, keep looking through the convertcsv
      while((boroComp(linedata[9].substring(2,5),linedata2[4].substring(0,1)) && linedata[9].substring(5,15).equals(linedata2[4].substring(1,11))) == false){
            line2 = cs.readLine();
            try{
            linedata2 = line2.split(",(?=(?:[^\"]*\"[^\"]*\")*[^\"]*$)", -1);
        //    System.out.println(linedata2[4]);
          }catch(NullPointerException e){
        //    System.out.println("caught");
            break;
          }
            //somehow before it hits the last line of the csv, it needs to just say no match and move on

//need to restart the progress on readline for CS every time a correct comparison is made
        }
      //  System.out.println("not broken");
//if it is true, add the new line in
    //  System.out.println(line2);
  //    System.out.println(linedata2[0] + "," + linedata2[1] + "," + linedata2[2] + "," + linedata2[5]);
      //  System.out.println(line + linedata2[0] + linedata2[1] + linedata2[2] + linedata2[5]);
        pw.write(line + "," + linedata2[0] + "," + linedata2[1] + "," + linedata2[2] + "," + linedata2[5] + "\n");
//reset the buffered reader
        cs.close();
        cs = new BufferedReader(new FileReader("convertcsv.csv"));
//reprime the String
        line2 = cs.readLine();
        linedata2 = line2.split(",(?=(?:[^\"]*\"[^\"]*\")*[^\"]*$)", -1);
      }
        r.close();
        cs.close();
}
catch( IOException ioException ) {
    System.out.println("Exception: "+ioException);
}

pw.flush();
}
}

Here's a line of my csv data, sorted from the fcc

geojson编辑和阅读，假装我是菜鸟

0 个答案: