;despuvwt2.pro despikes sonic anemometer data using a simple variance 
;threshhold technique. Spikes found in any of the four variables are replaced
;by badvals in all four variables from the sonic (u,v,w,t).
;Use is as follows:
;           despuvwt2,u,v,w,t,nsig,badval
;Where
;              input |   nsig = multiple of standard deviation to use as
;                    |          the threshhold value for despiking
;                    |badval = -999., a bad value marker
;
;       input/output | u,v,w = wind velocities from sonic anemometer (m/s)
;                    |     t = virtual temperature from sonic anemometer (C)
;
;Written by K.Davis? V.Sinha?
;Modified by BWBerger 8/99 to add descriptional header and to remove old
;commented out lines dealing with counting badvals.

pro despuvwt2,u,v,w,t,nsig,badval

despike,u,nsig,badval,hnew
despike,v,nsig,badval,hnew
despike,w,nsig,badval,hnew
despike,t,nsig,badval,hnew

;Place badvals in all variables if one has a spike.
;This is done by creating a template that keeps track of all badvals
;and then places them in each variable.
ggu=where(u eq badval)
ggv=where(v eq badval)
ggw=where(w eq badval)
ggt=where(t eq badval)

template=fltarr(n_elements(u))

if (ggu(0) gt -1) then template(ggu)=badval
if (ggv(0) gt -1) then template(ggv)=badval
if (ggw(0) gt -1) then template(ggw)=badval
if (ggt(0) gt -1) then template(ggt)=badval

gtemp=where(template eq badval)
if (gtemp(0) gt -1) then begin
  u(gtemp)=badval
  v(gtemp)=badval
  w(gtemp)=badval
  t(gtemp)=badval
endif

return
end