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HeikkiVesanto ♦
HeikkiVesanto ♦
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I have used the automated r.watershed tool in QGIS 2.18 (GRASS plugin) to conduct a watershed analysis (basin boundaries, flow direction, flow accumulation etc). I am relatively new to QGIS.

I'm stuck on the following operations:

1. Visualising flow direction arrows. I tried to convert the flow direction raster to a vector point file using GRASS>r.to-vect, but it keeps crashing (not responding/no error message). Please can anyone recommend a workflow for this (converting the file + visualising arrows)?

2. Burning stream network into the DEM. I created a polyline file from the flow accumulation raster, to join up 'missing' channels. After converting the polyline to a raster, the new raster has a smaller extent than the original DEM. Thus, the SAGA>Hydrology>'Burn stream network into DEM' tool won't operate with rasters of different extents.

I have used the automated r.watershed tool in QGIS 2.18 (GRASS plugin) to conduct a watershed analysis (basin boundaries, flow direction, flow accumulation etc). I am relatively new to QGIS.

I'm stuck on the following operations:

1. Visualising flow direction arrows. I tried to convert the flow direction raster to a vector point file using GRASS>r.to-vect, but it keeps crashing (not responding/no error message). Please can anyone recommend a workflow for this (converting the file + visualising arrows)?

2. Burning stream network into the DEM. I created a polyline file from the flow accumulation raster, to join up 'missing' channels. After converting the polyline to a raster, the new raster has a smaller extent than the original DEM. Thus, the SAGA>Hydrology>'Burn stream network into DEM' tool won't operate with rasters of different extents.

I have used the automated r.watershed tool in QGIS 2.18 (GRASS plugin) to conduct a watershed analysis (basin boundaries, flow direction, flow accumulation etc).

I'm stuck on the following operations:

1. Visualising flow direction arrows. I tried to convert the flow direction raster to a vector point file using GRASS>r.to-vect, but it keeps crashing (not responding/no error message). Please can anyone recommend a workflow for this (converting the file + visualising arrows)?

2. Burning stream network into the DEM. I created a polyline file from the flow accumulation raster, to join up 'missing' channels. After converting the polyline to a raster, the new raster has a smaller extent than the original DEM. Thus, the SAGA>Hydrology>'Burn stream network into DEM' tool won't operate with rasters of different extents.

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edit approved Feb 8, 2017 at 14:48
Oto Kaláb
edit approved Feb 8, 2017 at 14:48
Oto Kaláb
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I have used the automated r.watershed tool in QGIS 2.18 (GRASS plugin) to conduct a watershed analysis (basin boundaries, flow direction, flow accumulation etc). I am relatively new to QGIS.

I'm stuck on the following operations:

1. Visualising flow direction arrows. I tried to convert the flow direction raster to a vector point file using GRASS>r.to-vect, but it keeps crashing (not responding/no error message). Please can anyone recommend a workflow for this (converting the file + visualising arrows)?

2. Burning stream network into the DEM. I created a polyline file from the flow accumulation raster, to join up 'missing' channels. After converting the polyline to a raster, the new raster has a smaller extent than the original DEM. Thus, the SAGA>Hydrology>'Burn stream network into DEM' tool won't operate with rasters of different extents.

Many thanks, Mike

PS I am relatively new to QGIS!

I have used the automated r.watershed tool in QGIS 2.18 (GRASS plugin) to conduct a watershed analysis (basin boundaries, flow direction, flow accumulation etc).

I'm stuck on the following operations:

1. Visualising flow direction arrows. I tried to convert the flow direction raster to a vector point file using GRASS>r.to-vect, but it keeps crashing (not responding/no error message). Please can anyone recommend a workflow for this (converting the file + visualising arrows)?

2. Burning stream network into the DEM. I created a polyline file from the flow accumulation raster, to join up 'missing' channels. After converting the polyline to a raster, the new raster has a smaller extent than the original DEM. Thus, the SAGA>Hydrology>'Burn stream network into DEM' tool won't operate with rasters of different extents.

Many thanks, Mike

PS I am relatively new to QGIS!

I have used the automated r.watershed tool in QGIS 2.18 (GRASS plugin) to conduct a watershed analysis (basin boundaries, flow direction, flow accumulation etc). I am relatively new to QGIS.

I'm stuck on the following operations:

1. Visualising flow direction arrows. I tried to convert the flow direction raster to a vector point file using GRASS>r.to-vect, but it keeps crashing (not responding/no error message). Please can anyone recommend a workflow for this (converting the file + visualising arrows)?

2. Burning stream network into the DEM. I created a polyline file from the flow accumulation raster, to join up 'missing' channels. After converting the polyline to a raster, the new raster has a smaller extent than the original DEM. Thus, the SAGA>Hydrology>'Burn stream network into DEM' tool won't operate with rasters of different extents.

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Michael_01
Michael_01
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How to display Flow Direction arrows + Burn Stream Netwok in QGIS?

I have used the automated r.watershed tool in QGIS 2.18 (GRASS plugin) to conduct a watershed analysis (basin boundaries, flow direction, flow accumulation etc).

I'm stuck on the following operations:

1. Visualising flow direction arrows. I tried to convert the flow direction raster to a vector point file using GRASS>r.to-vect, but it keeps crashing (not responding/no error message). Please can anyone recommend a workflow for this (converting the file + visualising arrows)?

2. Burning stream network into the DEM. I created a polyline file from the flow accumulation raster, to join up 'missing' channels. After converting the polyline to a raster, the new raster has a smaller extent than the original DEM. Thus, the SAGA>Hydrology>'Burn stream network into DEM' tool won't operate with rasters of different extents.

Many thanks, Mike

PS I am relatively new to QGIS!