[postgis-users] issue with ST_AsEWKB

Sat Mar 18 08:21:40 PDT 2023

As you noted in IRC, you are using libgeos and libgeos_c  and not liblwgeom.

I used geosnop to check (and so did grayshade)

This is testing with my geos 3.10.1

geosop  -a 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 -f wkt

yields:

MULTILINESTRING ((180 -16.152929687500006, 179.84814453125 -16.21425781250001, 179.78886718750005 -16.221484375000003, 179.7150390625 -16.207617187500006, 179.63525390625 -16.223242187500006, 179.5517578125 -16.24990234375001, 179.47509765625 -16.29414062500001, 179.35917968750005 -16.3798828125, 179.29355468750003 -16.39863281250001, 179.224609375 -16.40517578125001, 179.09140625000003 -16.4375, 178.96054687500003 -16.48281250000001, 178.86572265625 -16.5400390625, 178.80507812500002 -16.631445312500006, 178.74453125000002 -16.63417968750001, 178.68632812500005 -16.665625000000006, 178.63427734375 -16.648535156250006, 178.58359375000003 -16.621875000000003, 178.56777343750002 -16.663867187500003, 178.5419921875 -16.700488281250003, 178.51376953125003 -16.72607421875, 178.49746093750002 -16.787890625000003, 178.6037109375 -16.800585937500003, 178.63808593750002 -16.85126953125001, 178.6650390625 -16.920019531250006, 178.70664062500003 -16.976171875000006, 178.8029296875 -16.9521484375, 178.88369140625002 -16.886035156250003, 178.950390625 -16.90400390625001, 179.0068359375 -16.900195312500003, 179.05546875000005 -16.813574218750006, 179.20234375 -16.712695312500003, 179.30048828125 -16.71035156250001, 179.32333984375003 -16.718066406250003, 179.34599609375005 -16.76972656250001, 179.375 -16.7919921875, 179.41933593750002 -16.80654296875001, 179.46542968750003 -16.80605468750001, 179.58896484375003 -16.78701171875001, 179.71474609375002 -16.74355468750001, 179.82080078125 -16.736914062500006, 179.9279296875 -16.744433593750003, 179.89003906250002 -16.6669921875, 179.90595703125 -16.583593750000006, 179.92656250000005 -16.55166015625001, 179.93037109375 -16.51943359375001, 179.8849609375 -16.51845703125001, 179.841015625 -16.53750000000001, 179.69707031250005 -16.631933593750006, 179.56816406250005 -16.74746093750001, 179.56416015625 -16.63691406250001, 179.619140625 -16.52773437500001, 179.74814453125003 -16.4462890625, 179.79384765625002 -16.37031250000001, 179.84824218750003 -16.30166015625001, 179.99921875 -16.168554687500006))

So geos does not seem to be at fault here either.  Which leaves something in your C code.

From: Regina Obe [mailto:lr at pcorp.us] 
Sent: Saturday, March 18, 2023 10:38 AM
To: 'PostGIS Users Discussion' <postgis-users at lists.osgeo.org>
Subject: RE: [postgis-users] issue with ST_AsEWKB

Can you provide the exact C lines you are using to extract.

I just ran this:

SELECT ST_AsText('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'::geometry );

And it outputs Y fine.  ST_AsText uses liblwgeom.  So perhaps a typo something in your code or some dependency issue.

MULTILINESTRING((180 -16.152929687500006,179.84814453125 -16.21425781250001,179.78886718750005 -16.221484375000003,179.7150390625 -16.207617187500006,179.63525390625 -16.223242187500006,179.5517578125 -16.24990234375001,179.47509765625 -16.29414062500001,179.35917968750005 -16.3798828125,179.29355468750003 -16.39863281250001,179.224609375 -16.40517578125001,179.09140625000003 -16.4375,178.96054687500003 -16.48281250000001,178.86572265625 -16.5400390625,178.80507812500002 -16.631445312500006,178.74453125000002 -16.63417968750001,178.68632812500005 -16.665625000000006,178.63427734375 -16.648535156250006,178.58359375000003 -16.621875000000003,178.56777343750002 -16.663867187500003,178.5419921875 -16.700488281250003,178.51376953125003 -16.72607421875,178.49746093750002 -16.787890625000003,178.6037109375 -16.800585937500003,178.63808593750002 -16.85126953125001,178.6650390625 -16.920019531250006,178.70664062500003 -16.976171875000006,178.8029296875 -16.9521484375,178.88369140625002 -16.886035156250003,178.950390625 -16.90400390625001,179.0068359375 -16.900195312500003,179.05546875000005 -16.813574218750006,179.20234375 -16.712695312500003,179.30048828125 -16.71035156250001,179.32333984375003 -16.718066406250003,179.34599609375005 -16.76972656250001,179.375 -16.7919921875,179.41933593750002 -16.80654296875001,179.46542968750003 -16.80605468750001,179.58896484375003 -16.78701171875001,179.71474609375002 -16.74355468750001,179.82080078125 -16.736914062500006,179.9279296875 -16.744433593750003,179.89003906250002 -16.6669921875,179.90595703125 -16.583593750000006,179.92656250000005 -16.55166015625001,179.93037109375 -16.51943359375001,179.8849609375 -16.51845703125001,179.841015625 -16.53750000000001,179.69707031250005 -16.631933593750006,179.56816406250005 -16.74746093750001,179.56416015625 -16.63691406250001,179.619140625 -16.52773437500001,179.74814453125003 -16.4462890625,179.79384765625002 -16.37031250000001,179.84824218750003 -16.30166015625001,179.99921875 -16.168554687500006))

and I got:

\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

Seems good but when I process this string with libgeom or libgeom_c or
a handmade C routine, I rather got this:

Geometry: MULTILINESTRING ((180.0000000000000000 0.0000000000000000,
179.5356445312500000 0.0000000000000000, 179.7876464843750455
0.0000000000000000, 179.6955078124997272 0.0000000000000000,
179.6352539062500000 0.0000000000000000, 179.5322265625000000
0.0000000000000000, 179.1625976562500000 0.0000000000000000,
179.0454589843750455 0.0000000000000000, 179.2934733072917197
0.0000000000000000, 179.2246093750000000 0.0000000000000000,
179.0705729166667197 0.0000000000000000, 178.6272135416667197
0.0000000000000000, 178.5336914062500000 0.0000000000000000,
178.7855468750000227 0.0000000000000000, 178.7250000000000227
0.0000000000000000, 178.6667968750000455 0.0000000000000000,
178.6330566406250000 0.0000000000000000, 178.5627604166667197
0.0000000000000000, 178.5665527343750227 0.0000000000000000,
178.5419921875000000 0.0000000000000000, 178.5136881510417197
0.0000000000000000, 178.1642089843750227 0.0000000000000000,
178.6037109374997272 0.0000000000000000, 178.6368652343750227
0.0000000000000000, 178.6650390625000000 0.0000000000000000,
178.7053385416667197 0.0000000000000000, 178.7833984374997272
0.0000000000000000, 178.5711914062500227 0.0000000000000000,
178.6378906249997272 0.0000000000000000, 179.0068359375000000
0.0000000000000000, 179.0359375000000455 0.0000000000000000,
179.2023437499997272 0.0000000000000000, 179.2992675781247272
0.0000000000000000, 179.0107584635417197 0.0000000000000000,
179.0334960937500455 0.0000000000000000, 179.0625000000000000
0.0000000000000000, 179.1056152343750227 0.0000000000000000,
179.1333170572917197 0.0000000000000000, 179.5693522135417197
0.0000000000000000, 179.6939941406250227 0.0000000000000000,
179.5083007812500000 0.0000000000000000, 179.5958984374997272
0.0000000000000000, 179.5763183593750227 0.0000000000000000,
179.5727050781247272 0.0000000000000000, 179.5945312500000455
0.0000000000000000, 179.5983398437497272 0.0000000000000000,
179.5724609374997272 0.0000000000000000, 179.5089843749997272
0.0000000000000000, 179.6958496093750455 0.0000000000000000,
179.5669433593750455 0.0000000000000000, 179.5629394531247272
0.0000000000000000, 179.5996093750000000 0.0000000000000000,
179.7285319010417197 0.0000000000000000, 179.7938476562500227
0.0000000000000000, 179.5356608072917197 0.0000000000000000,
179.6671874999997272 0.0000000000000000))

Oops, the y part is always 0.0000 What's wrong ???

Thank you again for everything

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