Hi,
Have you been able to read your data into Ferret? UTC simply means
Coordinated Universal Time, but what is the data unit? Seconds,
maybe? and since what time origin? Your data source should tell you
more than just "UTC".
Ferret will be able to convert those data to time steps once one
knows that. You would read in the three variables, define a time
axis using the first one, and RESHAPE your u and v components to
that time axis. Fill in the right things in the DEFINE AXIS command,
and you should be set.
yes? file/var="tsec, zero, u, v" my_data.dat
yes? define axis/t/units=seconds/t0="???" timeax = tsec
yes? let ucomp = reshape(u,t[gt=timeax])
yes? let vcomp = reshape(v,t[gt=timeax])
It would be a good idea to add /UNITS= on the LET commands to
give the velocity components their correct units. Then you should
be able to try the stick_vectors script to make a plot.
Ansley
On 6/30/2014 5:42 AM, 'Don DNA' via
_OAR PMEL Ferret Users wrote:
I read answer
from ferret userlist regarding stick plot from here, and
I don't have much knowledge about ferret, even to read
source code
I have "UTC date, u - component, v-component "
I am interested to calculate time shift, can
someone please help me to calculate time shift
for line segments,
My
data looks something like this
UTC
data, Zero, U-comp, V-component
379987200000,0,
-3.969,0.596
382665600000,0, -4.578,-1.001
385084800000,0,1.593,0.484
387763200000,0, -1.622,1.58
Can
someone please explain me, time shift for
above input, I actually did not understand
this " from (c*t,
0) to (c*t+u(t), v(t))", if I just add utc
date to U(t) - component I will get very
close value and I will not get slope,
please help me..
|