I have a string with a bunch of latitude and longitudes like this
LINESTRING (-79.0578544444577 43.0929133770364, -79.0559554404751 43.0929995585932, -79.0540564364926 43.09308574015, -79.0504086322323 43.0931797561892, -79.0503228015438 43.0911427096913)
and I want to get the coordinates out of the string into an array. I know this can be done with string splitting but I dont understand how to write the expression to get just the coordinates from the string.
can someone help me outwith this
( and last )", " and you will get String[] array that will contain pairs like "-79.0578544444577 43.0929133770364","-79.0559554404751 43.0929995585932",..." " on each of that pair to get another String[] array, this time containing "-79.0578544444577", "43.0929133770364"You could also use regex to find numbers in form [optional -][one or two digits][dot][more than one digits]. Such pattern could look like "-?\\d{1,2}[.]\\d+"
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Coordinates {
static class LatLon {
double lat;
double lon;
public LatLon( double lat, double lon ) {
this.lat = lat;
this.lon = lon;
}
@Override public String toString(){ return lat + ", " + lon; }
}
public static void main( String[] args ){
String info =
"LINESTRING (" +
"-79.0578544444577 43.0929133770364, " +
"-79.0559554404751 43.0929995585932, " +
"-79.0540564364926 43.09308574015, " +
"-79.0504086322323 43.0931797561892, " +
"-79.0503228015438 43.0911427096913)";
Pattern p = Pattern.compile( "[^\\(]+\\(([^\\)]+).*" );
Matcher m = p.matcher( info );
if( m.matches()) {
List< LatLon > coordinates = new java.util.LinkedList<>();
String[] coords = m.group( 1 ).split( "," );
for( int i = 0; i < coords.length; ++i ) {
String[] latLon = coords[i].trim().split( " " );
coordinates.add(
new LatLon(
Double.parseDouble( latLon[0] ),
Double.parseDouble( latLon[1] )));
}
System.out.println( coordinates );
}
}
}
Outputs:
[-79.0578544444577, 43.0929133770364, -79.0559554404751, 43.0929995585932, -79.0540564364926, 43.09308574015, -79.0504086322323, 43.0931797561892, -79.0503228015438, 43.0911427096913]
If you're happy having them all in one array:
String str = "LINESTRING (-79.0578544444577 43.0929133770364, -79.0559554404751 43.0929995585932, -79.0540564364926 43.09308574015, -79.0504086322323 43.0931797561892, -79.0503228015438 43.0911427096913)";
String[] arr = str.split("\\(|\\)")[1].split(",? ");
for (String s: arr)
System.out.println(a);
split("\\(|\\)") means split on ( or ). So that would be {"LINESTRING ", "-79...", ""}.
[1] because this is the position containing "-79...".
split(",? ") means split on , followed by a space or just a space.
If you want to extract the coordinates in pairs:
for (int i = 0; i < arr.length; i += 2)
{
System.out.println("coordinate 1 = "+arr[i]);
System.out.println("coordinate 2 = "+arr[i+1]);
}
If LineString is the name of your variable and what is inside the parenthesis its value (excluding parenthesis) then :
String[] coords = LINESTRING.split(" ");
should work !
Try this:
String[] coordinates = LINESTRING.split(",*\\s+");
This should immediately split both by space and by comma. This regular expression looks for zero or more commas and then one or more whitespace characters as the delimiter.
