Hi everyone.

I made a 2-D hydrodynamic model in another software (Matlab). The resulting output is a velocity field. I have exported results in an ASCII file containing 4 columns: x,y,u,v which correspond respectively to longitude, latitude, east component, north component.

I would like to know if it was possible in ArcGIS to plot a vector filed from my results.

Thank in advance,

Phil

I made a 2-D hydrodynamic model in another software (Matlab). The resulting output is a velocity field. I have exported results in an ASCII file containing 4 columns: x,y,u,v which correspond respectively to longitude, latitude, east component, north component.

I would like to know if it was possible in ArcGIS to plot a vector filed from my results.

Thank in advance,

Phil

Don't know if you already solved this interesting problem?

I believe you will need to first convert U and V to Angle (A) and Length (L) of vectors. I suggest you copy your data to an Excel spreadsheet and do the calculations there. If you place U in column D and V in column E, you may then use the following formulas to calculate A and L:

A = ARCTAN(E2/D2)*180/PI()

L = KVROD(D2^2+E2^2)

Import the table data to ArcGIS. Convert to shapefile or featureclass.

You may now set the point symbology using Categories, Select Unique values/ many fields, Specify value fields A and L. Right click a symbol and select properties for all symbols. Find an arrow that points towards the right (you can in fact use and arrow, and change the direction of it to make it point right).

In the Advanced symbol settings, set the Rotation angle to base on field A - artihmetic. And set the size of the points (arrows) to base on field L.

Hope this helps,

Eva