Error generating a curvilinear grid

[camillecouzi@yahoo.fr]

Hello Mohiders,

I am trying to generate a curvilinear grid: I am working on Fjords and I want to make a nested model inside a big regional model that I have already created. I want to do this submodel on a specific fjord, a part of this fjord (so my area is like an open chanel with some little islands every where).
I have selected the coeast lines that I need for this specific region. When I go to Mohid GIS -> Data items -> new data item -> curvilinear grid, then I put the name of the output file which will contain this grid, and then I select my coast lines of the chanel. A message error appear:

Code: Select all

Less than 3 corners in the image region
Error generating the grid, please check log file for details

I don't really understand the message, and also: could you tell me what is NPPE? (and could you confirm me that NX and NY are the number of horizontal and vertical cells?)

Thank you in advance for your help
Have a nice day!!

[luis_at_mohid.com]

Hi Camille,

Please find some more info here:

http://www.mohid.com/forum/viewtopic.php?t=26

It can be difficult to generate a curvilinear grid. You'll need some patience and perseverance.

Good luck,
Luis

[rafael_fergo@hotmail.com]

Code:
Less than 3 corners in the image region
Error generating the grid, please check log file for details

i think the problem is that you didnt define the polygon corners yet.
to do that first you have to render the polygon vertex.
(just one click over the polygon and press F4 and then in render box option mark the option render vertex, in case of your gackground being BLACK , then go to style and chance the text color to white.)

to define the corners , chose the option ''define polygon corner'' with your polygon selected , just in a tool box at the left side of the normal selection arrow tool icon.

after that, you ll have to click on the vertex to define the R and L
>>see more here<<
viewtopic.php?t=26
>>see more here<<

NX and NY compose your grid resolution basicaly

like : NY = 1000
:NX = 500

than your gird will be a retangular 1000x500

NPPE = is the Number of Points Per Edge. It is the minimum number of grid vertices you will have between two consecutive vertices of your boundary.

HOPE IT HELPS =)