> Hi Yuan, > Still no luck. > I created some value plots to see what's up with the data. > Data are indeed in degrees. I saw no negative values. > A value plot of cos(d*0.1745), which converts degrees to radians, just > gives 1's everywhere. No surprise there as cos(0)=1. > A value plot of cos(d), where d is degrees, gives expected values (based > on the value plot of original directions). > So, I retried my vector plot. > Ranges are -1 to 1 for the vectors (but really, every one of them ought > to be 1). I also tried a range of 0-2, just for fun. I varied vector > size, vertical position, line width...no luck. > But I see that you got a plot, so maybe you can tell me, explicitly, > what steps you took? > thanks, > alan Alan, I still have no luck to reproduce the image I sent you. It is better to use a formula, I have this formula tested: def flowVectors(field): a=newName(sin(field),"a") b=newName(cos(field),"b") return makeVector(a,b) Let me know if you have trouble adding this formula, I will going to add this to the py library too. Yuan > > On 4/14/2011 1:44 PM, Unidata IDV Support wrote: > >> Full Name: Alan Bol > >> Email Address: address@hidden > >> Organization: COMET > >> Package Version: 2.9u2 build date:2010-10-04 19:14 UTC > >> Operating System: Windows 7 > >> Hardware: Java: home: C:\Program Files (x86)\IDV_2.9u2\jre version: > >> 1.6.0_20 j3d:1.5.2 fcs (build4) > >> Description of problem: Hi guys, > >> I've got a gridded file of ocean wave directions (degrees) that I'd like > >> to plot as vectors. I made a stab at it but nothing shows up on the > >> display. > >> Here's what I did: > >> 1. chose the file. > >> 2. field sector/formulas/make flow vector from u and v > >> 3. for u and v, I chose Misc/define a formula > >> 4. for u, I entered sin(d), the selected my data file for d. > >> 5. for v, I entered cos(d), and again chose my data file for d. > >> 6. then, when I create display, nothing shows. But it doesn't show any > >> errors, either. > >> Any ideas? > >> > >> attached bundle and data file. > >> thanks, > >> alan > >> > >> > > Alan, > > I think your data is between +/-360 degree, you need to convert to > > radian. Also, in the vector display control, change the range to -1 to 1. > > See the attached. > > > > > > Yuan > > > > Ticket Details > > =================== > > Ticket ID: VIH-663165 > > Department: Support IDV > > Priority: Normal > > Status: Closed > > -- > Alan Bol > Project Lead | Scientist | Instructional Designer > The COMET Program | www.comet.ucar.edu > 303.497.8334 voice | 8491 fax > > Ticket Details =================== Ticket ID: VIH-663165 Department: Support IDV Priority: Normal Status: Closed
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