[Geotools-gt2-users] Re moving all features in a datastore...
Hejhej,
I've come up with a way to remove all features of a datastore... However,
I'm quite sure that there are more efficient ways to do this, getting rid of
this awkward iteration. Maybe someone can enlighten me.
Thanks very much in advance.
Markus
Code, created for shapefiles...
ShapefileDataStore src...;
try {
String typeName = src.getTypeNames()[0];
DefaultTransaction tran = new DefaultTransaction(RemoveAll);
FeatureStore stor = (FeatureStore)
src.getFeatureSource(typeName);
stor.setTransaction(tran);
FeatureCollection coll =
src.getFeatureSource(typeName).getFeatures();
FeatureIterator iter = coll.features();
FilterFactory fact =
CommonFactoryFinder.getFilterFactory(GeoTools.getDefaultHints());
SetFeatureId toRemove = new HashSetFeatureId();
while (iter.hasNext()) {
Feature ft = iter.next();
toRemove.add(fact.featureId(ft.getID()));
}
iter.close();
Filter filter = fact.id(toRemove);
try {
stor.removeFeatures(filter);
tran.commit();
}
catch (Exception ex) {
System.out.println(something wrong...);
tran.rollback();
}
} catch (Exception ex) {
ex.printStackTrace();
}
--
View this message in context:
http://www.nabble.com/Removing-all-features-in-a-datastore...-tp14753911p14753911.html
Sent from the geotools-gt2-users mailing list archive at Nabble.com.
-
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace
___
Geotools-gt2-users mailing list
Geotools-gt2-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
Re: [Geotools-gt2-users] Re moving all features in a datastore...
leaffan ha scritto: Hejhej, I've come up with a way to remove all features of a datastore... However, I'm quite sure that there are more efficient ways to do this, getting rid of this awkward iteration. Maybe someone can enlighten me. FeatureStore stor = (FeatureStore) src.getFeatureSource(typeName); stor.removeFeatures(Filter.INCLUDE); (that's on gt2 2.4.x, on previous versions that Filter.INCLUDE should be Filter.NONE). Cheers Andrea - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace ___ Geotools-gt2-users mailing list Geotools-gt2-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
Re: [Geotools-gt2-users] Re moving all features in a datastore...
leaffan ha scritto:
Hejhej,
I've come up with a way to remove all features of a datastore... However,
I'm quite sure that there are more efficient ways to do this, getting rid of
this awkward iteration. Maybe someone can enlighten me.
FeatureStore stor = (FeatureStore) src.getFeatureSource(typeName);
stor.removeFeatures(Filter.INCLUDE);
(that's on gt2 2.4.x, on previous versions that Filter.INCLUDE should
be Filter.NONE).
Cheers
Andrea
Thanks very much in advance.
Markus
Code, created for shapefiles...
ShapefileDataStore src...;
try {
String typeName = src.getTypeNames()[0];
DefaultTransaction tran = new DefaultTransaction(RemoveAll);
FeatureStore stor = (FeatureStore)
src.getFeatureSource(typeName);
stor.setTransaction(tran);
FeatureCollection coll =
src.getFeatureSource(typeName).getFeatures();
FeatureIterator iter = coll.features();
FilterFactory fact =
CommonFactoryFinder.getFilterFactory(GeoTools.getDefaultHints());
SetFeatureId toRemove = new HashSetFeatureId();
while (iter.hasNext()) {
Feature ft = iter.next();
toRemove.add(fact.featureId(ft.getID()));
}
iter.close();
Filter filter = fact.id(toRemove);
try {
stor.removeFeatures(filter);
tran.commit();
}
catch (Exception ex) {
System.out.println(something wrong...);
tran.rollback();
}
} catch (Exception ex) {
ex.printStackTrace();
}
-
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace
___
Geotools-gt2-users mailing list
Geotools-gt2-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
[Geotools-gt2-users] Splitting LineStrings at their intersection
Hi,
After loading a shapefile (ESRI), I created a graph using a
DirectedLineStringGraphGenerator. The creation went fine but when using a
DijkstraShortestPathFinder.getPath() on it, I noticed that there was a
problem because it returned null. Apparently, the linestring graph generator
does not take internal intersections of
lines into account when building the graph. Hence, I decided to code a
routine to split the LineStrings at their intersection as advised there:
http://www.nabble.com/Re%3A-LineString-Graph-Traversal-p1489791.html
The problem is that My routine is taking forever to do the splitting.
Either, I'm doing it wrong or it is not optimized enough. After waiting for
10 minutes, it is still not finished (although, the shapefile is not that
big). Could someone have a look at my function and see what the problem is?
Thanks in advance,
Best regards,
Chris.
private VectorLineString splitLines(VectorLineString lines) {
for (int i = 0; i lines.size() - 1; ++i) {
LineString l1 = (LineString) lines.get(i);
for (int j = i+1; j lines.size(); ++j) {
LineString l2 = (LineString) lines.get(j);
Geometry gc = l1.intersection(l2);
if (gc.getNumGeometries() 0) {
// Intersection
Point p = (Point) gc.getGeometryN(0);
if (l2.getStartPoint() != p l2.getEndPoint() != p) {
// Remove old line from table
lines.remove(j);
// Split into two lines
Coordinate[] c = new
Coordinate[]{(l2.getStartPoint()).getCoordinate(), p.getCoordinate()};
lines.add(j, new LineString(new
CoordinateArraySequence(c), new GeometryFactory()));
c = new Coordinate[]{p.getCoordinate(),
(l2.getEndPoint()).getCoordinate()};
lines.add(j, new LineString(new
CoordinateArraySequence(c), new GeometryFactory()));
++j;
//System.out.println(Created 1 line);
}
if (l1.getStartPoint() != p l1.getEndPoint() != p) {
// Remove old line from table
lines.remove(i);
// Split into two lines
Coordinate[] c = new
Coordinate[]{(l1.getStartPoint()).getCoordinate(), p.getCoordinate()};
LineString new_l = new LineString(new
CoordinateArraySequence(c), new GeometryFactory());
lines.add(i, new_l);
c = new Coordinate[]{p.getCoordinate(),
(l1.getEndPoint()).getCoordinate()};
lines.add(i+1, new LineString(new
CoordinateArraySequence(c), new GeometryFactory()));
++j;
//System.out.println(Created 1 line);
l1 = (LineString) new_l;
}
}
}
}
return lines;
}
-
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace___
Geotools-gt2-users mailing list
Geotools-gt2-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
Re: [Geotools-gt2-users] Splitting LineStrings at their intersection
Hi Chris, I would have to mock up some data and test it but I dont think the problem is the method but in the management of the data structure. The code is modifying the same list it is iterating over... which is generally not a great idea. I recommend restructuring the algorithm so that when two new lines are created they are added to a separate list. When the outer loop termines add the new lines to the original list and repeat the algorithm terminating when there are no more new lines. Hope that helps. I could be wrong as i said since i have not run the code. If you find you continue to have the same problem let us know . -Justin Chris wrote: Hi, After loading a shapefile (ESRI), I created a graph using a DirectedLineStringGraphGenerator. The creation went fine but when using a DijkstraShortestPathFinder.getPath() on it, I noticed that there was a problem because it returned null. Apparently, the linestring graph generator does not take internal intersections of lines into account when building the graph. Hence, I decided to code a routine to split the LineStrings at their intersection as advised there: http://www.nabble.com/Re%3A-LineString-Graph-Traversal-p1489791.html The problem is that My routine is taking forever to do the splitting. Either, I'm doing it wrong or it is not optimized enough. After waiting for 10 minutes, it is still not finished (although, the shapefile is not that big). Could someone have a look at my function and see what the problem is? Thanks in advance, Best regards, Chris. !DSPAM:4007,4787a0db264908992556831! - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace !DSPAM:4007,4787a0db264908992556831! ___ Geotools-gt2-users mailing list Geotools-gt2-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users !DSPAM:4007,4787a0db264908992556831! -- Justin Deoliveira The Open Planning Project http://topp.openplans.org - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace ___ Geotools-gt2-users mailing list Geotools-gt2-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
Re: [Geotools-gt2-users] Splitting LineStrings at their intersection
I added some debug, and apparently, the LineString intersection is not due to my algorithm. It happens approximately 12 times in the first loop iteration, then it does not happen anymore. This was probably due to my shapefile. So I chose to ignore the LineString intersections and now my algorithm has been running for approximately half an hour and it is the fourth iteration of the while loop (still unfinished). I added some debug to see how many LineStrings were created for each iteration: Added 2200 new lines Added 7666 new lines Added 26234 new lines Is my algorithm ok? Is it normal it is taking so long? Is there any way I can optimize this? If not, I guess I need to save the result somewhere in a file and work from the result from now on because it is taking too much time. Regards, Chris. On Jan 11, 2008 9:28 PM, Chris [EMAIL PROTECTED] wrote: I tried to use another Vector as you advised. This way, the size the the lines Vector is not changing while iterating on it. I'm joining the new code to this mail. It is taking quite some time (2-3 minutes) but this time I got an exception: java.lang.ClassCastException: com.vividsolutions.jts.geom.LineStringcannot be cast to com.vividsolutions.jts.geom.Point at this line: Point p = (Point) gc.getGeometryN(0); where gc is the intersection between the two lines. Apparently, the intersection between two LineStrings can be a LineString. I guess this means that the two lines are identical? How could this happen? Is my algorithm still wrong? or maybe I should just ignore when this case happens? Regards, Chris. On Jan 11, 2008 7:28 PM, Justin Deoliveira [EMAIL PROTECTED] wrote: Hi Chris, I would have to mock up some data and test it but I dont think the problem is the method but in the management of the data structure. The code is modifying the same list it is iterating over... which is generally not a great idea. I recommend restructuring the algorithm so that when two new lines are created they are added to a separate list. When the outer loop termines add the new lines to the original list and repeat the algorithm terminating when there are no more new lines. Hope that helps. I could be wrong as i said since i have not run the code. If you find you continue to have the same problem let us know . -Justin Chris wrote: Hi, After loading a shapefile (ESRI), I created a graph using a DirectedLineStringGraphGenerator. The creation went fine but when using a DijkstraShortestPathFinder.getPath() on it, I noticed that there was a problem because it returned null. Apparently, the linestring graph generator does not take internal intersections of lines into account when building the graph. Hence, I decided to code a routine to split the LineStrings at their intersection as advised there: http://www.nabble.com/Re%3A-LineString-Graph-Traversal-p1489791.html The problem is that My routine is taking forever to do the splitting. Either, I'm doing it wrong or it is not optimized enough. After waiting for 10 minutes, it is still not finished (although, the shapefile is not that big). Could someone have a look at my function and see what the problem is? Thanks in advance, Best regards, Chris. !DSPAM:4007,4787a0db264908992556831! - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace !DSPAM:4007,4787a0db264908992556831! ___ Geotools-gt2-users mailing list Geotools-gt2-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users !DSPAM:4007,4787a0db264908992556831! -- Justin Deoliveira The Open Planning Project http://topp.openplans.org - Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace___ Geotools-gt2-users mailing list Geotools-gt2-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
Re: [Geotools-gt2-users] Splitting LineStrings at their intersection
I tried to use another Vector as you advised. This way, the size the the
lines Vector is not changing while iterating on it. I'm joining the new code
to this mail.
It is taking quite some time (2-3 minutes) but this time I got an exception:
java.lang.ClassCastException: com.vividsolutions.jts.geom.LineString cannot
be cast to com.vividsolutions.jts.geom.Point
at this line:
Point p = (Point) gc.getGeometryN(0);
where gc is the intersection between the two lines. Apparently, the
intersection between two LineStrings can be a LineString. I guess this means
that the two lines are identical? How could this happen? Is my algorithm
still wrong? or maybe I should just ignore when this case happens?
Regards,
Chris.
On Jan 11, 2008 7:28 PM, Justin Deoliveira [EMAIL PROTECTED] wrote:
Hi Chris,
I would have to mock up some data and test it but I dont think the
problem is the method but in the management of the data structure. The
code is modifying the same list it is iterating over... which is
generally not a great idea.
I recommend restructuring the algorithm so that when two new lines are
created they are added to a separate list. When the outer loop termines
add the new lines to the original list and repeat the algorithm
terminating when there are no more new lines.
Hope that helps. I could be wrong as i said since i have not run the
code. If you find you continue to have the same problem let us know .
-Justin
Chris wrote:
Hi,
After loading a shapefile (ESRI), I created a graph using a
DirectedLineStringGraphGenerator. The creation went fine but when using
a DijkstraShortestPathFinder.getPath() on it, I noticed that there was a
problem because it returned null. Apparently, the linestring graph
generator does not take internal intersections of
lines into account when building the graph. Hence, I decided to code a
routine to split the LineStrings at their intersection as advised there:
http://www.nabble.com/Re%3A-LineString-Graph-Traversal-p1489791.html
The problem is that My routine is taking forever to do the splitting.
Either, I'm doing it wrong or it is not optimized enough. After waiting
for 10 minutes, it is still not finished (although, the shapefile is not
that big). Could someone have a look at my function and see what the
problem is?
Thanks in advance,
Best regards,
Chris.
!DSPAM:4007,4787a0db264908992556831!
-
Check out the new SourceForge.net Marketplace.
It's the best place to buy or sell services for
just about anything Open Source.
http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace
!DSPAM:4007,4787a0db264908992556831!
___
Geotools-gt2-users mailing list
Geotools-gt2-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
!DSPAM:4007,4787a0db264908992556831!
--
Justin Deoliveira
The Open Planning Project
http://topp.openplans.org
private VectorLineString splitLines(VectorLineString lines) {
VectorLineString new_lines = new VectorLineString();
boolean first = true;
int imax = lines.size()-1;
do {
if(!first) {
imax = new_lines.size()-1; // Optimization
// Merge the two vectors
lines.addAll(0, new_lines);
new_lines.clear();
}
for (int i = 0; i imax; ++i) {
LineString l1 = (LineString) lines.get(i);
int jmax = lines.size();
for (int j = i + 1; j jmax; ++j) {
LineString l2 = (LineString) lines.get(j);
Geometry gc = l1.intersection(l2);
if (gc.getNumGeometries() 0) {
// Intersection
Point p = (Point) gc.getGeometryN(0);
if (l2.getStartPoint() != p l2.getEndPoint() != p) {
// Remove old line from table
lines.remove(j);
// Split into two lines
Coordinate[] c = new
Coordinate[]{(l2.getStartPoint()).getCoordinate(), p.getCoordinate()};
lines.add(j, new LineString(new
CoordinateArraySequence(c), new GeometryFactory()));
c = new Coordinate[]{p.getCoordinate(),
(l2.getEndPoint()).getCoordinate()};
new_lines.add(new LineString(new
CoordinateArraySequence(c), new GeometryFactory()));
}
if (l1.getStartPoint() != p l1.getEndPoint() != p) {
// Remove old line from table
Re: [Geotools-gt2-users] Splitting LineStrings at their intersection
Chris wrote:
I added some debug, and apparently, the LineString intersection is not
due to my algorithm. It happens approximately 12 times in the first loop
iteration, then it does not happen anymore. This was probably due to my
shapefile.
So I chose to ignore the LineString intersections and now my algorithm
has been running for approximately half an hour and it is the fourth
iteration of the while loop (still unfinished). I added some debug to
see how many LineStrings were created for each iteration:
Added 2200 new lines
Added 7666 new lines
Added 26234 new lines
Is my algorithm ok? Is it normal it is taking so long? Is there any way
I can optimize this? If not, I guess I need to save the result somewhere
in a file and work from the result from now on because it is taking too
much time.
Intersection is quite an expensive operation. I am not surprised it is
taking this long with any non-trivial amount of data. Luckily there are
some easy ways to optimize this. The best way to be to use a spatial
index instead of looping through every line string and doing an
intersection. So the the first step of your algorithm will be to
populate the index with all of your lines. Its pretty easy to use:
SpatialIndex index = ...;
for ( LineString l : lines ) {
index.insert( l.getEnvelopInternal(), l );
}
Then you can replace the second loop with a lookup in the index.
//current line being processed
LineString l = ...;
//do a looup in the index
List close = index.query( l.getEnvelopeInternal() );
//do intersection on close lines
for ( LineString c : close ) {
l.intersect( c );
}
.. etc..
This will greatly reduce the number of intersections you have to do and
you should see a pretty drastic performance improvement. There are two
implementations of com.vividsolutions.jts.index.SpatialIndex: STRTree
and QuadTree. The STRTree will give you best performance but it is
static, which means you cant update over the stage of your algorithm
which you will probably want to do with the new lines that are produced.
So you will probably have to just use a the QuadTree implementation.
Either one should suffice in this case.
Try that and let me know how it works.
-Justin
Regards,
Chris.
On Jan 11, 2008 9:28 PM, Chris [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED] wrote:
I tried to use another Vector as you advised. This way, the size the
the lines Vector is not changing while iterating on it. I'm joining
the new code to this mail.
It is taking quite some time (2-3 minutes) but this time I got an
exception:
java.lang.ClassCastException: com.vividsolutions.jts.geom.LineString
cannot be cast to com.vividsolutions.jts.geom.Point
at this line:
Point p = (Point) gc.getGeometryN(0);
where gc is the intersection between the two lines. Apparently, the
intersection between two LineStrings can be a LineString. I guess
this means that the two lines are identical? How could this happen?
Is my algorithm still wrong? or maybe I should just ignore when this
case happens?
Regards,
Chris.
On Jan 11, 2008 7:28 PM, Justin Deoliveira [EMAIL PROTECTED]
mailto:[EMAIL PROTECTED] wrote:
Hi Chris,
I would have to mock up some data and test it but I dont think the
problem is the method but in the management of the data
structure. The
code is modifying the same list it is iterating over... which is
generally not a great idea.
I recommend restructuring the algorithm so that when two new
lines are
created they are added to a separate list. When the outer loop
termines
add the new lines to the original list and repeat the algorithm
terminating when there are no more new lines.
Hope that helps. I could be wrong as i said since i have not run the
code. If you find you continue to have the same problem let us
know .
-Justin
Chris wrote:
Hi,
After loading a shapefile (ESRI), I created a graph using a
DirectedLineStringGraphGenerator. The creation went fine but
when using
a DijkstraShortestPathFinder.getPath() on it, I noticed that
there was a
problem because it returned null. Apparently, the linestring graph
generator does not take internal intersections of
lines into account when building the graph. Hence, I decided
to code a
routine to split the LineStrings at their intersection as
advised there:
http://www.nabble.com/Re%3A-LineString-Graph-Traversal-p1489791.html
http://www.nabble.com/Re%3A-LineString-Graph-Traversal-p1489791.html
The problem is that My routine is taking forever to do the
splitting.
Either, I'm doing it wrong or it is not optimized enough.
After
