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comment How to snap and move circles by the center?
You can use the move feature of the digitizing toolbar. Before doing that you can set a snapping threshold at settings/snapping options and there select the point/polygon layer you want to sanp to and set a treshold of 10-15 pixels. After that you have to select the layer where you want to move features, put this layer in edit mode, select the feature you want to move and chose the move feature icon and move your feature where you want to be.
Sep
9
comment How set correct options for displaying a grid in QGIS composer?
It even does change the hemisphere identifier (O or W) depending the language you are using. Having this option in composer is a great tool for final maps.
Sep
9
comment How set correct options for displaying a grid in QGIS composer?
I tested and it is working correctly, now everything shows ok!
Jul
31
comment Lat Long to Useable values in QGIS
In order to convert deg/min second to decimal degrees I do it with the following formula in a spreadsheet deg+(min/60)+(sec/3600). for western longitudes and southern latitudes I do as follows -1*(deg+(min/60)+(sec/3600)). Usually I isolate the results by copy and paste values add a column with a name/identifier and save as a csv comma delimited file. Then you can use the "add delimited text layer" plug in to load the points in qgis. Hope it helps
Jul
31
comment Lat Long to Useable values in QGIS
In order to convert deg/min second to decimal degrees I do it with the following formula in a spreadsheet
Jul
10
comment Cropping or removing borders (not NoData) from multiple scanned and georeferenced maps (ArcMap or QGIS)
First try to see what is the value of the black edge with the identifying tool. Then you can try to covert your file to another/same format and definig the null value and keeping the files in the same crs (raster/conversion/translate(convert format))
Jun
30
comment Open Layers Plugin and QGis 2.4
I also think that gene´s comments qualify as an answer. Following the link it clarifies the issues.
May
13
comment How to clip a lines vector layer to a polygon layer in QGIS?
why not trying to clip the raster file? take in to account that both layer must be in the same crs also.
May
8
comment Scale and Z factor have no effect on hillshade analysis in QGIS
When you are using a DEM with latlon coordinates in decimal degrees and vertical units in meters you have to set the scale (ratio of vertical units to horizontal units) to 111120. I tried with a couple of DEMs from Aster I have not a problem. This setting aplies not only to hillshading but also for slope calculations. Hope it helps
Apr
11
comment How to change polygon display/symbol properties in QGIS while digitizing?
try setting the layers' transparency also to 50%
Feb
19
comment Missing Georeferencer
Thanks, I was used to see it without activating it in manage and install plugins. Now there is a little glitch, since after I invoke the georeferencer, the georeferencer appears, do not respond for a little moment and I have an error stating "bad allocation". After that i can play with the georeferencer.
Jan
30
comment Step by step LCP Analysis QGIS 2.0
I do not know what version of Qgis you are running. I use 2.01 64 under win 7. R. drain gives me a big blag raster. The path is there but I can not see it. The way I handle the problem was to conver th r.drain raster to vecto with r.to.vect.line. Then the path is visible.
Jan
28
comment Step by step LCP Analysis QGIS 2.0
I run r.cost with the native resolution of your dem and I have no problem, bear in mind that I am using qgis 2.01 64 in win7 with an I7 and 16gb of ram, so it was fast (les than a minute)
Jan
28
comment Step by step LCP Analysis QGIS 2.0
Hello,sorry for the delay, I was able to run rwalk,and rdrain with the model you mentioned. The only thing I changed was the raster resolution. As I understand when you defined your region , the raster resolution is set to 1 (in this case 1 meter). So look for an icon that tells "grass region settings" and change the resolution to something esle more than one. Your dem is 5, so try with 5 or 10. Hope it helps
Jan
28
comment Mapinfo and qgis file's datum problem
The lenght of a degree depends on your latitude check this out:csgnetwork.com/degreelenllavcalc.html
Jan
21
comment Step by step LCP Analysis QGIS 2.0
Try also this: gis.stackexchange.com/questions/77629/…
Jan
21
comment Step by step LCP Analysis QGIS 2.0
You can verify that everything is ok in GRASS by opening a file called wind. This file is located in the Permanet folder of the region you defined. You can open the wind file with a text editor. If it states your zone correctly you are good to perform any operation in your rasters. One trick is instead of using a projected CRS try doing it with a lat-lon CRS. This will force you to reproject all your data but it worked for me
Jan
21
comment Step by step LCP Analysis QGIS 2.0
You can try this. First prepare all the basic layers in Qgis. Slope, rasters from vectors. Define step by step as directed in the tutorial I mentioned, the region and the map set using the GRASS ui, not the qgis one. Then do the import the rasters (slope, dems, rasterized vectors). Reclasify what you need. Export to geotif. Go back to qgis and perform the union with qgis raster calculator. This will give you the friction surface you need for rwalk or r.cost. Now using grass under qgis import your friction surface and try to run r.cost or r.walk and r. drain. Sounds cumbersome but it worked
Jan
19
comment Step by step LCP Analysis QGIS 2.0
I experienced tha same problem as you with a grass region defined in QGIS. I solved the problem by using the GRASS UI (included in your qgis installation) and following this tutorial ing.unitn.it/~grass/docs/tutorial_64_en/htdocs/esercitazione/…. Once defined correctly the region I was able to use UTM data without problems
Jan
19
comment Step by step LCP Analysis QGIS 2.0
Why use the raster calculator?Suppouse you are giving the slopes 75% of weight and the rivers 25%. Both layers can create a new raster with their sum (for instance) showing your friction surface.