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When I try to use the v.net.flow tool in QGIS, the output datasets have a value of 0 for every feature in the flow column. Almost every other v.net tool works, such as v.net.steiner and v.net.distance.

How do I get the v.net.flow tool to actually output the proper values?**

I have attached the log below.

Processing algorithm… Algorithm 'v.net.flow' starting… Input parameters: { 'GRASS_MIN_AREA_PARAMETER' : 0.0001, 'GRASS_OUTPUT_TYPE_PARAMETER' : 0, 'GRASS_REGION_PARAMETER' : None, 'GRASS_SNAP_TOLERANCE_PARAMETER' : -1, 'GRASS_VECTOR_DSCO' : '', 'GRASS_VECTOR_EXPORT_NOCAT' : True, 'GRASS_VECTOR_LCO' : '-r', 'arc_backward_column' : None, 'arc_column' : 'Shape_Leng', 'cut' : 'F:/Work Stuff/SteinerTree/Steiner/Section 4/cut.shp', 'input' : 'F:\Work Stuff\SteinerTree\Steiner\NETWORK3TRY.shp|layername=NETWORK3TRY', 'node_column' : None, 'output' : 'F:/Work Stuff/SteinerTree/Steiner/Section 4/flow.shp', 'points' : 'F:/Work Stuff/SteinerTree/Steiner/Section 5/Section5.shp', 'sink_cats' : '', 'sink_where' : 'TYPE = 0', 'source_cats' : '', 'source_where' : 'TYPE = 1', 'threshold' : 50 }

g.proj -c proj4="+proj=tmerc +lat_0=0 +lon_0=-76.5 +k=0.9999 +x_0=304800 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs" v.in.ogr min_area=0.0001 snap=-1.0 input="F:\Work Stuff\SteinerTree\Steiner\NETWORK3TRY.shp" layer="NETWORK3TRY" output="vector_5c906e50cfc9823" --overwrite -o v.in.ogr min_area=0.0001 snap=-1.0 input="F:\Work Stuff\SteinerTree\Steiner\Section 5\Section5.shp" output="vector_5c906e50cfc9824" --overwrite -o g.region n=5027309.435160724 s=5024626.0554929385 e=363198.1515355515 w=360651.9582503296 v.net -s input=vector_5c906e50cfc9823 points=vector_5c906e50cfc9824 output=net5c906e50d046625 operation=connect threshold=50.0 v.db.connect -o map=net5c906e50d046625 table=vector_5c906e50cfc9824 layer=2 v.net.flow input=net5c906e50d046625 source_where="TYPE = 1" sink_where="TYPE = 0" arc_column=Shape_Leng output=outpute1098a53ef12487c97f2a35692f70e87 cut=cute1098a53ef12487c97f2a35692f70e87 --overwrite v.out.ogr type="line" input="outpute1098a53ef12487c97f2a35692f70e87" output="F:/Work Stuff/SteinerTree/Steiner/Section 4/flow.shp" format="ESRI_Shapefile" layer=1 -c --overwrite v.out.ogr type="line" input="cute1098a53ef12487c97f2a35692f70e87" output="F:/Work Stuff/SteinerTree/Steiner/Section 4/cut.shp" format="ESRI_Shapefile" layer=1 -c --overwrite Starting GRASS GIS... WARNING: Concurrent mapset locking is not supported on Windows Executing ... C:\OSGEO4~1\bin>chcp 1252 1>NUL C:\OSGEO4~1\bin>g.proj -c proj4="+proj=tmerc +lat_0=0 +lon_0=-76.5 +k=0.9999 +x_0=304800 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs" Default region was updated to the new projection, but if you have multiple mapsets g.region -d should be run in each to update the region from the default Projection information updated C:\OSGEO4~1\bin>v.in.ogr min_area=0.0001 snap=-1.0 input="F:\Work Stuff\SteinerTree\Steiner\NETWORK3TRY.shp" layer="NETWORK3TRY" output="vector_5c906e50cfc9823" --overwrite -o Over-riding projection check Check if OGR layer contains polygons... 0..2..4..6..8..10..12..14..16..18..20..22..24..26..28..30..32..34..36..38..40..42..44..46..48..50..52..54..56..58..60..62..64..66..68..70..72..74..76..78..80..82..84..86..88..90..92..94..96..98..100 Creating attribute table for layer ... Column name renamed to Importing 8460 features (OGR layer )... 0..2..4..6..8..10..12..14..16..18..20..22..24..26..28..30..32..34..36..38..40..42..44..46..48..50..52..54..56..58..60..62..64..66..68..70..72..74..76..78..80..82..84..86..88..90..92..94..96..98..100 ----------------------------------------------------- Building topology for vector map ... Registering primitives... C:\OSGEO4~1\bin>v.in.ogr min_area=0.0001 snap=-1.0 input="F:\Work Stuff\SteinerTree\Steiner\Section 5\Section5.shp" output="vector_5c906e50cfc9824" --overwrite -o Over-riding projection check Check if OGR layer contains polygons... 0..2..4..6..8..10..12..14..16..18..20..22..24..26..28..30..32..34..36..38..40..42..44..46..48..50..52..54..56..58..60..62..64..66..68..70..72..74..76..78..80..82..84..86..88..90..92..94..96..98..100 Creating attribute table for layer ... Importing 888 features (OGR layer )... 0..2..4..6..8..10..12..14..16..18..20..22..24..26..28..30..32..34..36..38..40..42..44..46..48..50..52..54..56..58..60..62..64..66..68..70..72..74..76..78..80..82..84..86..88..90..92..94..96..98..100 ----------------------------------------------------- Building topology for vector map ... Registering primitives... C:\OSGEO4~1\bin>g.region n=5027309.435160724 s=5024626.0554929385 e=363198.1515355515 w=360651.9582503296 C:\OSGEO4~1\bin>v.net -s input=vector_5c906e50cfc9823 points=vector_5c906e50cfc9824 output=net5c906e50d046625 operation=connect threshold=50.0 Copying features... 2..5..8..11..14..17..20..23..26..29..32..35..38..41..44..47..50..53..56..59..62..65..68..71..74..77..80..83..86..89..92..95..98..100 Building topology for vector map ... Registering primitives... Copying attributes... Building topology for vector map ... Registering primitives... v.net complete. 0 lines (network arcs) written to output. C:\OSGEO4~1\bin>v.db.connect -o map=net5c906e50d046625 table=vector_5c906e50cfc9824 layer=2 The table is now part of vector map and may be deleted or overwritten by GRASS modules Select privileges were granted on the table C:\OSGEO4~1\bin>v.net.flow input=net5c906e50d046625 source_where="TYPE = 1" sink_where="TYPE = 0" arc_column=Shape_Leng output=outpute1098a53ef12487c97f2a35692f70e87 cut=cute1098a53ef12487c97f2a35692f70e87 --overwrite Building graph... Registering arcs... 1..3..5..7..9..11..13..15..17..19..21..23..25..27..29..31..33..35..37..39..41..43..45..47..49..51..53..55..57..59..61..63..65..67..69..71..73..75..77..79..81..83..85..87..89..91..93..95..97..99..100 Flattening the graph... Graph was built Writing the output... 1..3..5..7..9..11..13..15..17..19..21..23..25..27..29..31..33..35..37..39..41..43..45..47..49..51..53..55..57..59..61..63..65..67..69..71..73..75..77..79..81..83..85..87..89..91..93..95..97..99..100 Building topology for vector map ... Registering primitives... Building topology for vector map ... Registering primitives... C:\OSGEO4~1\bin>v.out.ogr type="line" input="outpute1098a53ef12487c97f2a35692f70e87" output="F:/Work Stuff/SteinerTree/Steiner/Section 4/flow.shp" format="ESRI_Shapefile" layer=1 -c --overwrite WARNING: 888 points found, but not requested to be exported. Verify 'type' parameter. Exporting 8460 features... 5..11..17..23..29..35..41..47..53..59..65..71..77..83..89..95..100 v.out.ogr complete. 8460 features (Line String type) written to (ESRI_Shapefile format). C:\OSGEO4~1\bin>v.out.ogr type="line" input="cute1098a53ef12487c97f2a35692f70e87" output="F:/Work Stuff/SteinerTree/Steiner/Section 4/cut.shp" format="ESRI_Shapefile" layer=1 -c --overwrite WARNING: No lines found, but requested to be exported. Will skip this feature type. WARNING: No attribute table found -> using only category numbers as attributes Exporting 0 features... WARNING: Output layer is empty, no features written v.out.ogr complete. 0 features (Line String type) written to (ESRI_Shapefile format). C:\OSGEO4~1\bin>exit Execution of finished. Cleaning up default sqlite database ... Cleaning up temporary files... Execution completed in 20.03 seconds Results: {'cut': , 'output': }

Loading resulting layers Algorithm 'v.net.flow' finished

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