'define u1000=ugrdprs(lev=1000)'
'define u950=ugrdprs(lev=950)'
'define u900=ugrdprs(lev=900)'
'define u850=ugrdprs(lev=850)'
'define u800=ugrdprs(lev=800)'
'define u750=ugrdprs(lev=750)'
'define u700=ugrdprs(lev=700)'
'define u650=ugrdprs(lev=650)'
'define u600=ugrdprs(lev=600)'
'define u550=ugrdprs(lev=550)'
'define u500=ugrdprs(lev=500)'
'define u450=ugrdprs(lev=450)'
'define u400=ugrdprs(lev=400)'

'define v1000=vgrdprs(lev=1000)'
'define v950=vgrdprs(lev=950)'
'define v900=vgrdprs(lev=900)'
'define v850=vgrdprs(lev=850)'
'define v800=vgrdprs(lev=800)'
'define v750=vgrdprs(lev=750)'
'define v700=vgrdprs(lev=700)'
'define v650=vgrdprs(lev=650)'
'define v600=vgrdprs(lev=600)'
'define v550=vgrdprs(lev=550)'
'define v500=vgrdprs(lev=500)'
'define v450=vgrdprs(lev=450)'
'define v400=vgrdprs(lev=400)'

'define umean=(u1000+u950+u900+u850+u800+u750+u700+u650+u600+u550+u500+u450+u400)/13.0'
'define vmean=(v1000+v950+v900+v850+v800+v750+v700+v650+v600+v550+v500+v450+v400)/13.0'
'define ushear=u500-u1000'
'define vshear=v500-v1000'
'define shear=sqrt(ushear*ushear+vshear*vshear)'
'define umotion=((umean+(7.5/(shear))*vshear))'
'define vmotion=((vmean-(7.5/(shear))*ushear))'

'define srh1=((u950-umotion)*(v1000-vmotion)-(u1000-umotion)*(v950-vmotion))'
'define srh2=((u900-umotion)*(v950-vmotion)-(u950-umotion)*(v900-vmotion))'
'define srh3=((u850-umotion)*(v900-vmotion)-(u900-umotion)*(v850-vmotion))'
'define srh4=((u800-umotion)*(v850-vmotion)-(u850-umotion)*(v800-vmotion))'
'define srh5=((u750-umotion)*(v800-vmotion)-(u800-umotion)*(v750-vmotion))'
'define srh6=((u700-umotion)*(v750-vmotion)-(u750-umotion)*(v700-vmotion))'

'define srh3km=srh1+srh2+srh3+srh4+srh5+srh6'
'define srh1km=srh1+srh2'