Hi All, After a few messages back and forth between ourselves, Byoin Huang and I determined that his question was about plotting time series in general, and that it comes down to whether the axis is specified as dates or time steps. If an axis is specified as time steps without specific dates: def axis/t=1:600:12/units=months ty plot sin(t[gt=ty]/100) Then the time axis is labeled simply with months, and the full plotting capabilities of PPLUS for plotting time axes is not available. The axis will always have units of months, and Ferret cannot make the automatic conversion to label the axis with years. To allow Ferret to convert the time axis to years, we need to define the axis using dates, either in the /T= specification, or with a time origin /T0= define axis/t=1-jan-1950:1-jan-2000:1/units=months ty plot sin(t[gt=ty]/100) or define axis/t=1:160:1/units=months/t0=1-jan-1900 ty plot sin(t[gt=ty]/100) Ansley Manke Boyin Huang wrote:
Dear All: I used monthly out put (130*12 month), and calculated EOFs (space pattern and time series) using annual average. Because of the regrid to annual average, the time axis in time series is set as TYEAR = 7, 19, 31, 43, 55, 67, ...in unit of months when saving a CDF file. When I plot the time series, using let x11 = eof_tm[i=1] plot/nolab/line=($ln1)/set x11 ppl yaxis ($y1),($y2),($dy) ppl xaxis ($x1),($x2),($dx) The label of X-axis is out of control: The ferret some how use a default value of x1, x2, and dx, and plot ticks of "0, 400, 800,1200" months. How can I control the X-axis, and plot the ticks of "0, 20, 40, 60, ..." years rather than in months? Or can I use unit of year rather than month when saving the CDF file?