I need your help

I try to read the radar velocity of the gulf of mexico.

nc=netcdfd('201009020700_HFRadar_USEGC_6km_rtv_SIO .nc') %read data
Latitudes=nc.VarArray(2).Data; %read latitude
Longitud=nc.VarArray(3).Data; %read longitude
vx=nc.VarArray(4).Data; %read vx
vy=nc.VarArray(5).Data; %read vy
avx=nc.VarArray(6).Data; %read filter fx
avy the filter for "y" is null


I done zero all point with the following values -32768, 21376, 32256

vx=0.01*vx*fx %aply the filter in the vx and the scale factor

vx=0.01*vx %aply the scale factor over velocities
vy=0.01*vy %

finally the velocity is:
v=sqrt(vx*vx +vy*vy)

but the problem is the velocities are the order 300 m/s!!!!!
What is wrong?

regards,
Carolina


I Copy the information of the file


$ncdump -h pp.nc

netcdf pp {
dimensions:
time = UNLIMITED ; // (1 currently)
lat = 460 ;
lon = 701 ;
nSites = 33 ;
nSites_maxStrlen = 25 ;
nProcParam = 7 ;
variables:
int time(time) ;
time:standard_name = "time" ;
time:units = "seconds since 1970-01-01" ;
time:calendar = "gregorian" ;
float lat(lat) ;
lat:standard_name = "latitude" ;
lat:units = "degrees_north" ;
float lon(lon) ;
lon:standard_name = "longitude" ;
lon:units = "degrees_east" ;
short u(time, lat, lon) ;
u:standard_name = "surface_eastward_sea_water_velocity" ;
u:units = "m s-1" ;
u:_FillValue = -32768s ;
u:scale_factor = 0.01f ;
u:ancillary_variables = "DOPx" ;
short v(time, lat, lon) ;
v:standard_name = "surface_northward_sea_water_velocity" ;
v:units = "m s-1" ;
v:_FillValue = -32768s ;
v:scale_factor = 0.01f ;
v:ancillary_variables = "DOPy" ;
short DOPx(time, lat, lon) ;
DOPx:long_name = "longitudinal dilution of precision" ;
DOPx:comment = "The longitudinal dilution of precision (DOPx) represents the\n",
"contribution of the radars\' configuration geometry to\n",
"uncertainty in the eastward velocity estimate (u). DOPx is a\n",
"direct multiplier of the standard error in obtaining the\n",
"standard deviation for the eastward velocity estimate from the\n",
"least squares best fit. DOPx and DOPy are commonly used to\n",
"obtain the geometric dilution of precision\n",
"(GDOP = sqrt(DOPx^2 + DOPy^2)), a useful metric for filtering\n",
"errant velocities due to poor geometry." ;
DOPx:_FillValue = -32768s ;
DOPx:scale_factor = 0.01f ;
short DOPy(time, lat, lon) ;
DOPy:long_name = "latitudinal dilution of precision" ;
DOPy:comment = "The latitudinal dilution of precision (DOPy) represents the\n",
"contribution of the radars\' configuration geometry to\n",
"uncertainty in the northward velocity estimate (v). DOPy is a\n",
"direct multiplier of the standard error in obtaining the\n",
"standard deviation for the northward velocity estimate from the\n",
"least squares best fit. DOPx and DOPy are commonly used to\n",
"obtain the geometric dilution of precision\n",
"(GDOP = sqrt(DOPx^2 + DOPy^2)), a useful metric for filtering\n",
"errant velocities due to poor geometry." ;
DOPy:_FillValue = -32768s ;
DOPy:scale_factor = 0.01f ;
float site_lat(nSites) ;
site_lat:long_name = "Contributing radar site latitudes" ;
site_lat:standard_name = "latitude" ;
site_lat:units = "degrees_north" ;
float site_lon(nSites) ;
site_lon:long_name = "Contributing radar site longitudes" ;
site_lon:standard_name = "longitude" ;
site_lon:units = "degrees_east" ;
char site_code(nSites, nSites_maxStrlen) ;
site_code:long_name = "Contributing radar site code" ;
char site_netCode(nSites, nSites_maxStrlen) ;
site_netCode:long_name = "Contributing radar site network affiliation code" ;
float procParams(nProcParam) ;
procParams:long_name = "RTV processing parameters" ;
procParams:comment = "\n",
"01) Maximum GDOP threshold\n",
"02) Maximum speed threshold (cm s-1)\n",
"03) Minimum number of sites required\n",
"04) Minimum number of radials required\n",
"05) Maximum angular gap to interpolate radial\n",
" data over (degrees, 0 = no interpolation)\n",
"06) Maximum gap in range to interpolate radial\n",
" data over (range-resolution, 0 = no interpolation)\n",
"07) Spatial search radius for radial solutions (km)" ;

// global attributes:
:netcdf_library_version = "netcdf library version \"3.6.3\" of Aug 14 2008 22:45:23 $" ;
:format_version = "HFRNet_1.0.0" ;
roduct_version = "HFRNet_1.1.05" ;
:Conventions = "CF-1.1" ;
:title = "Near-Real Time Surface Ocean Velocity" ;
:institution = "Scripps Institution of Oceanography" ;
:source = "Surface Ocean HF-Radar" ;
:history = "02-Sep-2010 10:35:12: Filtered U and V by GDOP < 1.25\n",
"02-Sep-2010 10:35:12: NetCDF file created" ;
:references = "Terrill, E. et al., 2006. Data Management and Real-time\n",
"Distribution in the HF-Radar National Network. Proceedings\n",
"of the MTS/IEEE Oceans 2006 Conference, Boston MA,\n",
"September 2006." ;
:creator_name = "Mark Otero" ;
:creator_email = "motero@mpl.ucsd.edu" ;
:creator_url = "http://cordc.ucsd.edu/projects/mapping/" ;
:summary = "Surface ocean velocities estimated from HF-Radar are\n",
"representitive of the upper 0.3 - 2.5 meters of the\n",
"ocean. The main objective of near-real time\n",
"processing is to produce the best product from\n",
"available data at the time of processing. Radial\n",
"velocity measurements are obtained from individual\n",
"radar sites through the HF-Radar Network and\n",
"processed to create near-real time velocities\n",
"(RTVs)" ;
:geospatial_lat_min = 21.73596f ;
:geospatial_lat_max = 46.49442f ;
:geospatial_lon_min = -97.88385f ;
:geospatial_lon_max = -57.23121f ;
:grid_resolution = "6km" ;
:grid_projection = "equidistant cylindrical" ;
:regional_description = "Unites States, East and Gulf Coast" ;
}