def radarcoords(cx,cy,cz): cs=sqrt(cx**2+cy**2) cele=propigation.elev_of_scan(cs,cz) caz=mathematics.vector_direction(cx,cy) return cs, caz, cele
def get_value_at_xyz(scan_list, x,y,z, var, **kwargs):
"""
scan_list: a list of scans
x,y,z: position to find value (interpolation position) in metres
var: parameter to interpolate (eg VR, DZ,...)
"""
#Generate a array of elevations for the scan list
#We use the minus onth (last) element in the scan as the radar has settled by then
elevs=array([scan['Elev'][-1] for scan in scan_list])
#pick the above and below elevations
s=sqrt(x**2+y**2)
az=mathematics.vector_direction(x,y)
baddata=kwargs.get('baddata',1.31072000e+05)
my_elevation=propigation.elev_of_scan(s,z)
elev_numbers=mathematics.where_fits(my_elevation, elevs)
#for each elevation pick the ray on either side of the point
if not(elev_numbers[0] == elev_numbers[1]):
#we are neither at the top or bottom
top_scan=scan_list[elev_numbers[1]]
bottom_scan=scan_list[elev_numbers[0]]
#Scan above the point ----------TOP ELEVATION-----------
#work out what gates to use (ie range in S direction)
sar=sqrt(top_scan['xar'][0,:]**2 + top_scan['yar'][0,:]**2)
gates=mathematics.where_fits(s, sar)
ds=sar[gates[1]]-sar[gates[0]]
if ds==0.0:
top_gates_comp=[0.5,0.5]
else:
top_gates_comp=[ abs(s-sar[gates[1]])/ds, abs(s-sar[gates[0]])/ds]
scan_order=top_scan['Azmth'].argsort()
fits_order=mathematics.where_fits(az, top_scan['Azmth'][scan_order])
ray_numbers=[scan_order[fits_order[0]], scan_order[fits_order[1]]]
d_angle=top_scan['Azmth'][ray_numbers[1]]-top_scan['Azmth'][ray_numbers[0]]
top_ang_comp=[abs(az-top_scan['Azmth'][ray_numbers[1]])/d_angle, abs(az-top_scan['Azmth'][ray_numbers[0]])/d_angle]
if fits_order[0] == fits_order[1]:
#we are near 360
azd=az
ray_numbers=[scan_order[-1], scan_order[0]]
d_angle=top_scan['Azmth'][ray_numbers[1]]-(top_scan['Azmth'][ray_numbers[0]]-360.0)
if az > d_angle: azd=az-360.0
top_ang_comp=[abs(azd-top_scan['Azmth'][ray_numbers[1]])/d_angle,abs(azd-(top_scan['Azmth'][ray_numbers[0]]-360.0))/d_angle ]
tp1=cond_lin_int(top_scan[var][ray_numbers[0], gates[0]], top_scan[var][ray_numbers[0], gates[1]], top_gates_comp)
tp2=cond_lin_int(top_scan[var][ray_numbers[1], gates[0]], top_scan[var][ray_numbers[1], gates[1]], top_gates_comp)
top_point=cond_lin_int(tp1, tp2, top_ang_comp)
top_z=(top_scan['zar'][ray_numbers[0], gates[0]]*top_gates_comp[0]+ top_scan['zar'][ray_numbers[0], gates[1]]*top_gates_comp[1])
#BOTTTTTTTTOOMMMMMMMMMMMM!
sar=sqrt(bottom_scan['xar'][0,:]**2 + bottom_scan['yar'][0,:]**2)
gates=mathematics.where_fits(s, sar)
ds=sar[gates[1]]-sar[gates[0]]
if ds==0.:
bottom_gates_comp=[0.5,0.5]
else:
bottom_gates_comp=[ abs(s-sar[gates[1]])/ds, abs(s-sar[gates[0]])/ds]
scan_order=bottom_scan['Azmth'].argsort()
fits_order=mathematics.where_fits(az, bottom_scan['Azmth'][scan_order])
ray_numbers=[scan_order[fits_order[0]], scan_order[fits_order[1]]]
d_angle=bottom_scan['Azmth'][ray_numbers[1]]-bottom_scan['Azmth'][ray_numbers[0]]
bottom_ang_comp=[abs(az-bottom_scan['Azmth'][ray_numbers[1]])/d_angle, abs(az-bottom_scan['Azmth'][ray_numbers[0]])/d_angle]
if fits_order[0] == fits_order[1]:
#we are near 360
azd=az
ray_numbers=[scan_order[-1], scan_order[0]]
d_angle=bottom_scan['Azmth'][ray_numbers[1]]-(bottom_scan['Azmth'][ray_numbers[0]]-360.0)
if az > d_angle: azd=az-360.0
bottom_ang_comp=[abs(azd-bottom_scan['Azmth'][ray_numbers[1]])/d_angle,abs(azd-(bottom_scan['Azmth'][ray_numbers[0]]-360.0))/d_angle ]
bp1=cond_lin_int(bottom_scan[var][ray_numbers[0], gates[0]], bottom_scan[var][ray_numbers[0], gates[1]], bottom_gates_comp)
bp2=cond_lin_int(bottom_scan[var][ray_numbers[1], gates[0]], bottom_scan[var][ray_numbers[1], gates[1]], bottom_gates_comp)
bottom_point=cond_lin_int(bp1, bp2, bottom_ang_comp)
bottom_z=(bottom_scan['zar'][ray_numbers[0], gates[0]]*bottom_gates_comp[0]+ bottom_scan['zar'][ray_numbers[0], gates[1]]*bottom_gates_comp[1])
#calculate components
d_z=top_z-bottom_z
#print d_z
z_comps=[abs(z-top_z)/d_z, abs(z-bottom_z)/d_z]
my_point=cond_lin_int(bottom_point, top_point, z_comps)
#bottom_point*z_comps[0]+top_point*z_comps[1]
else:
my_point=0.0
if "az_range" in kwargs.keys():
a1=kwargs['az_range'][0]
a2=kwargs['az_range'][0]
if a1 > a2: #we go through 360
if not((az >= a1) or (az <=a2)):
my_point=baddata
else:
if not((az >= a1) or (az <= a2)):
my_point=baddata
return my_point