Just a little thing to add to the last reply.

To search for a SEXTANTE algorithm about a given topic, use Sextante.alglist(<string_to_search>). For instance, in the case of searching for something containing "buffer", you would do

from sextante.core.Sextante import Sextante Sextante.alglist("buffer")

And you would get:

Grid Buffer------------------------------------------>saga:gridbuffer
Grid Proximity Buffer-------------------------------->saga:gridproximitybuffer
Shapes Buffer---------------------------------------->saga:shapesbuffer
Threshold Buffer------------------------------------->saga:thresholdbuffer
Fixed distance buffer-------------------------------->ftools:fixeddistancebuffer
Variable distance buffer----------------------------->ftools:variabledistancebuffer
r.buffer - Creates a raster map layer showing buffer zones surrounding cells that contain non-NULL category values.--->grass:r.buffer
v.buffer.angle--------------------------------------->grass:v.buffer.angl
v.buffer.column - Creates a buffer around features of given type.--->grass:v.buffer.column
v.buffer.distance - Creates a buffer around features of given type.--->grass:v.buffer.distance
v.buffer.minordistance------------------------------->grass:v.buffer.minordistance

That way, you can find the name of the algorithm to call (ftools:fixeddistancebuffer, in the example proposed in the reply above)

You can turn your script into a new algorithm in SEXTANTE. The SEXTANTE documentation has detailed information about that.

Just a little thing to add to the last reply.

To search for a SEXTANTE algorithm about a given topic, use Sextante.alglist(<string_to_search>). For instance, in the case of searching for something containing "buffer", you would do

>>> from sextante.core.Sextante import Sextante
>>> Sextante.alglist("buffer")

And you would get:

Grid Buffer------------------------------------------>saga:gridbuffer
Grid Proximity Buffer-------------------------------->saga:gridproximitybuffer
Shapes Buffer---------------------------------------->saga:shapesbuffer
Threshold Buffer------------------------------------->saga:thresholdbuffer
Fixed distance buffer-------------------------------->ftools:fixeddistancebuffer
Variable distance buffer----------------------------->ftools:variabledistancebuffer
r.buffer - Creates a raster map layer showing buffer zones surrounding cells that contain non-NULL category values.--->grass:r.buffer
v.buffer.angle--------------------------------------->grass:v.buffer.angl
v.buffer.column - Creates a buffer around features of given type.--->grass:v.buffer.column
v.buffer.distance - Creates a buffer around features of given type.--->grass:v.buffer.distance
v.buffer.minordistance------------------------------->grass:v.buffer.minordistance

That way, you can find the name of the algorithm to call (ftools:fixeddistancebuffer, in the example proposed in the reply above)

You can turn your script into a new algorithm in SEXTANTE. The SEXTANTE documentation has detailed information about that.