Difference between revisions of "R.sun"

From GRASS-Wiki
Jump to: navigation, search
(Time step: +pics)
m (fix cl opts)
Line 1: Line 1:
= r.sun =
 
 
 
== Help page ==
 
== Help page ==
  
Line 16: Line 14:
 
The following three images demonstrate the effects of using different time '''step''' parameters.
 
The following three images demonstrate the effects of using different time '''step''' parameters.
  
  r.sun -s elevin="gauss" glob_rad="rad.global.30minT" day=180
+
  r.sun -s elevin="gauss" glob_rad="rad.global.30minT" day=180 step=0.5
  
 
[[File:Gauss_30min.png|400px|thumb|center|Default 30 minute time step over a Gaussian mound.]]
 
[[File:Gauss_30min.png|400px|thumb|center|Default 30 minute time step over a Gaussian mound.]]
  
  
  r.sun -s elevin="gauss" glob_rad="rad.global.15minT" day=180
+
  r.sun -s elevin="gauss" glob_rad="rad.global.15minT" day=180 step=0.25
  
 
[[File:Gauss_15min.png|400px|thumb|center|15 minute time step over a Gaussian mound.]]
 
[[File:Gauss_15min.png|400px|thumb|center|15 minute time step over a Gaussian mound.]]
  
  
  r.sun -s elevin="gauss" glob_rad="rad.global.03minT" day=180
+
  r.sun -s elevin="gauss" glob_rad="rad.global.03minT" day=180 step=0.05
  
 
[[File:Gauss_03min.png|400px|thumb|center|3 minute time step over a Gaussian mound.]]
 
[[File:Gauss_03min.png|400px|thumb|center|3 minute time step over a Gaussian mound.]]

Revision as of 02:55, 19 May 2009

Help page

Tips

Testing

Create an artificial surface containing a Gaussian mound:

r.surf.volcano out=gauss method=gaussian kurtosis=1

Time step

The following three images demonstrate the effects of using different time step parameters.

r.sun -s elevin="gauss" glob_rad="rad.global.30minT" day=180 step=0.5
Default 30 minute time step over a Gaussian mound.


r.sun -s elevin="gauss" glob_rad="rad.global.15minT" day=180 step=0.25
15 minute time step over a Gaussian mound.


r.sun -s elevin="gauss" glob_rad="rad.global.03minT" day=180 step=0.05
3 minute time step over a Gaussian mound.



The 3 minute time step takes roughly ten times as long to run as the 30 minute timestep.