Question

我在尝试从CSV文件中绘制一些坐标时遇到了一些麻烦。我正在使用纬度和经度，然后我使用Web墨卡托（https://en.wikipedia.org/wiki/Web_Mercator#Formulas）转换它们，之后我将使用最小值和最大值并使用map（）函数将它们映射到之间的值0和500.但是，我收到以下错误：

总行数：6606

maxLat = 198987.05; minLat = 198986.94; maxLong = 110837.664; minLong = 110836.695 拉特＆amp;在映射之前很久：198986.27; 110840.68 拉特＆amp; map（）之后很久：-6142.857; 4112.9033 拉特＆amp;在norm（）之后很久：-6.142857; 4.112903

地图（NaN，198986.94,198987.05,0,500）调用，返回NaN（不是数字）

地图（NaN，110836.695,110837.664,0,500）被叫，返回NaN（不是数字）

我很感激如何解决错误或代码改进的任何建议。先感谢您。代码本身：

import java.util.Collections;

Table csvFile;

ArrayList<Float>times = new ArrayList<Float>();
ArrayList<Float>latitude = new ArrayList<Float>();
ArrayList<Float>longitude = new ArrayList<Float>();
ArrayList<Float>lap = new ArrayList<Float>();

ArrayList<Float>latitudeCal = new ArrayList<Float>();
ArrayList<Float>longitudeCal = new ArrayList<Float>();

float maxLat = 0;
float maxLong = 0;
float minLat = 0;
float minLong = 0;

void setup() {
  size(600, 800);
  csvFile = loadTable("RRData.csv", "header");

  int totalRows = csvFile.getRowCount();

  println("total number of rows: " + totalRows);

  for (TableRow row : csvFile.rows()) { 
    times.add(row.getFloat("Time"));
    latitude.add(normLat(row.getFloat("Latitude")));
    longitude.add(normLon(row.getFloat("Longitude")));
  }

  maxLat = latitude.get(0);
  maxLong = longitude.get(0);
  maxLat = latitude.get(0);
  maxLong = longitude.get(0);

  // Finding Max Values
  for (int i = 1; i < latitude.size() - 1; i++) {
    maxLat = max(maxLat, latitude.get(i));
    maxLong = max(maxLong, longitude.get(i));
    minLat = min(minLat, latitude.get(i));
    minLong = min(minLong, longitude.get(i));
  }

  println("maxLat = "  + maxLat + "; minLat = " + minLat + " ; maxLong = " + maxLong + "; minLong = " + minLong); 

  println("lat & long before mapping: " + latitude.get(0) + " ; " + longitude.get(0));

  println("lat & long after map(): " + map(latitude.get(0), minLat, maxLat, 0, 1000) + " ; " + map(longitude.get(0), minLong, maxLong, 0, 1000)); // map() doesn't worked as intended

  //Try Normalising
  println("lat & long after norm(): " + norm(latitude.get(0), minLat, maxLat) + " ; " + norm(longitude.get(0), minLong, maxLong));

  // Mapping 
  for (int  i = 0; i < latitude.size() - 1; i++) {
    float num = latitude.get(i);
    float num2 = longitude.get(i);
    //println(num);
    //println(num2);
    latitudeCal.add(map(num, minLat, maxLat, 0, 500));
    longitudeCal.add(map(num2, minLong, maxLong, 0, 500));
  }

}

float normLon(float lon) {
  lon = radians(lon);
  float a = (256 / PI) * pow(2, 10);
  float b = lon + PI;
  return a * b;
}

float normLat(float lat) {
  lat = radians(lat);
  float a = (256 / PI) * pow(2, 10);
  float b = tan(PI / 4 + lat / 2);
  float c = PI - log(b);
  return a * c;
}

void draw() {  
  background(51);
  for (int i = 0; i < times.size() - 1; i++) {
    noFill();
    ellipse(latitude.get(i), longitude.get(i), 20, 20);
  }
}

在处理中使用map（）时出现一些错误

0 个答案: