Re: [GRASS-user] SQL query in python scripts using v.to.rast

[Micha Silver]

Here's a correction to the format of the "where" clause that should work: import grass.script as gscript types = ("primary" , "secondary" , "tertiary" , "service" , "pedestrian" , "footway" , "residential" , "path") for typ in types:     where_str = ("type = '%s'" % typ)   # Added single quotes around the %s     outrast = "_".join(["type", typ])     gscript.run_command ("v.to.rast",             input = "road_clip",             type = "line",             where = where_str,             output = outrast,             use = "attr" , attribute_column = "cat") On 11/11/18 12:02 PM, Alessandro Sebastiani wrote: Hello to everybody ,  i tried with this piece of code, following suggestios by both: # note that for the moment i reduced the street types to 3 >>>types = ("primary" , "secondary" , "tertiary")        >>>for typ in types: >>>>    gscript.run_command ("v.to.rast" , input = "road_clip" , type = "line" , where = "type=%s" % typ , output = ("r"+typ) , use = "attr" , attribute_column = "cat")    nevertheless, i still get the following error message DBMI-SQLite driver error: Error in sqlite3_prepare(): SELECT cat FROM road_clip WHERE type=primary near "primary": syntax error DBMI-SQLite errore del driver: Error in sqlite3_prepare(): SELECT cat FROM road_clip WHERE type=primary near "primary": syntax error ERROR: Impossible to select recod from table <road_clip> Traceback (most recent call last):   File "/home/alessandro/Scrivania/script_grass/rast_quer_st ats_exp.py", line 6, in <module>     gscript.run_command ("v.to.rast" , input = "road_clip" , type = "line" , where = "type=%s" % typ , output = ("r"+typ) , use = "attr" , attribute_column = "cat")   File "/usr/lib/grass74/etc/python/grass/script/core.py", line 421, in run_command     return handle_errors(returncode, returncode, args, kwargs)   File "/usr/lib/grass74/etc/python/grass/script/core.py", line 332, in handle_errors     returncode=returncode) grass.exceptions.CalledModuleError: L'esecuzione del modulo None ['v.to.rast', 'use=attr', 'attribute_column=cat', 'type=line', 'input=road_clip', 'output=rprimary', 'where=type=primary'] è terminata con errori Processo terminato con codice di return diverso da zero 1. (Sun Nov 11 10:53:56 2018) Comando terminato (0 sec)                              I read both error message and my piece of code time again and again, i was not able to detect what i am doing wong! Il giorno ven 9 nov 2018 alle ore 13:15 Micha Silver <tsvi...@gmail.com> ha scritto: I would do as follows: (Notice that each street type will become a *separate* raster) On 11/9/18 1:49 PM, Alessandro Sebastiani wrote: Dear all i have a vector (downloaded from OpenStreetmap) with all the streets in my study area. Streets are divided in categories (there is a specific string column in the db). now i want to convert to raster each category separately. I now how to do that separately, but i was not able to automate that in a python script. here it is what i wrote: >>>import grass.script as gscript >>>types = ("primary" , "secondary" , "tertiary" , "service" , "pedestrian" , "footway" , "residential" , "path") >>>for typ in types:     where_str = ("type = %s" % typ)     outrast = "_".join(["type", typ])     gscript.run_command("v.to.rast",             input = "road_clip", type = "line", where = where_str,             output = outrast, use="attr", attribute_column = "cat" ) >>>>    gscript.run_command ("v.to.rast" , input = "road_clip" , type = "line" , where ="type"=typ , output = types, use = "attr" , attribute_column = "cat"). I got the following traceback:   File "/home/alessandro/GRASSDATA/5_citta_def/5_citt_def/.tmp /alessandro-Lenovo-G50-70/5500.6.py", line 6     gscript.run_command ("v.to.rast" , input = "road_clip" , type = "line" , where ="type"=typ , output = types, use = "attr" , attribute_column = "cat")                               ^ SyntaxError: invalid syntax i guess the syntax error is in the way i set the query, but i'm not sure. Thanks to everybody, _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user -- Micha Silver Ben Gurion Univ. Sde Boker, Remote Sensing Lab cell: +972-523-665918 _______________________________________________ grass-user mailing list grass-user@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/grass-user -- Micha Silver Ben Gurion Univ. Sde Boker, Remote Sensing Lab cell: +972-523-665918

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