| Re: Vector legend with PARTVELVEC [message #84218] |
Sun, 05 May 2013 04:25 |
Fabzi
Messages: 305
Registered: July 2010
|
Senior Member |
|
|
On 05/05/2013 12:26 AM, ljs15@fsmail.net wrote:
> Perhaps I misunderstand, but if you just want to draw a single arrowfor
> a legend, I would use cgArrow.pro (or arrow.pro), rather than partvelvec.
Yes, but the length of the arrow should correspond to the length of the
arrows drawn by partyvelec. Typically, you have a windfield to plot on
an image, and you now the (u,v) or your wind field and their (x,y)
positions in /data coordinates. for example, if your wind speed ranges
from 0 to 12. m.s-1, you might want to add a legend to your plot with an
arrow showing the length of a wind arrow of 10 m.s-1.
Anyways, I'll think about a version of partvelvec which provides an
ouptut structure (in /NORMAL coordinates) of the longest arrow it has
plotted and use cgArrow to draw the legend. This should be fine.
Thanks!
|
|
|
|
| Re: Vector legend with PARTVELVEC [message #84223 is a reply to message #84218] |
Sat, 04 May 2013 15:26  |
Sir Loin Steak
Messages: 42
Registered: January 2012
|
Member |
|
|
On Friday, May 3, 2013 6:25:08 PM UTC+1, wlandsman wrote:
> Perhaps I misunderstand, but if you just want to draw a single arrow for a legend, I would use cgArrow.pro (or arrow.pro), rather than partvelvec.
>
>
>
> --Wayne
>
>
>
> On Friday, May 3, 2013 12:43:11 PM UTC-4, Fabien wrote:
>
>> Hey IDLers,
>
>>
>
>>
>
>>
>
>> Maybe I haven't been searching hard enough but I did not find a way to
>
>>
>
>> use PARTVELVEC to draw only one vector as a legend vector. I guess I
>
>>
>
>> could do this myself by making my own partvelvec routine, but I thought
>
>>
>
>> this would be something the community might already have done.
>
>>
>
>>
>
>>
>
>> It is not that trivial since partvelvec draws in DATA coordinates, while
>
>>
>
>> the legend vector should be plotted outside the image. And the length of
>
>>
>
>> the legend should correspond to that of the plot of course ;-). I think
>
>>
>
>> this can only be done by modifying partvelvec so that it returns
>
>>
>
>> "something" that can be used to plot a legend afterwards. Like:
>
>>
>
>>
>
>>
>
>> cgImage, myImage
>
>>
>
>> partvelvec, vx, vy, px, py, /OVER, LEGEND_struc=legend ;output
>
>>
>
>> partvelvec_legend, legend, POSITION=poslegend, etc.
>
>>
>
>>
>
>>
>
>> Anyways, if someone did this already and is willing to share I would be
>
>>
>
>> very thankful. If not, I'm open to suggestions on how to do this the
>
>>
>
>> right way ;)
>
>>
>
>>
>
>>
>
>> Cheers,
>
>>
>
>>
>
>>
>
>> Fab
No, I think he wants to plot vectors with partvelvec, and also plot a vector outside the plot range to use as a legend (so you know what wind speed etc. the vector lengths represent).
I wanted to do something similar myself but couldn't think how, so in the plot description I just wrote 'the length of largest vector represents wind speeds of ...'. Not ideal, but I was in a rush!
|
|
|
|
| Re: Vector legend with PARTVELVEC [message #84231 is a reply to message #84223] |
Fri, 03 May 2013 10:25 |
wlandsman
Messages: 743
Registered: June 2000
|
Senior Member |
|
|
Perhaps I misunderstand, but if you just want to draw a single arrow for a legend, I would use cgArrow.pro (or arrow.pro), rather than partvelvec.
--Wayne
On Friday, May 3, 2013 12:43:11 PM UTC-4, Fabien wrote:
> Hey IDLers,
>
>
>
> Maybe I haven't been searching hard enough but I did not find a way to
>
> use PARTVELVEC to draw only one vector as a legend vector. I guess I
>
> could do this myself by making my own partvelvec routine, but I thought
>
> this would be something the community might already have done.
>
>
>
> It is not that trivial since partvelvec draws in DATA coordinates, while
>
> the legend vector should be plotted outside the image. And the length of
>
> the legend should correspond to that of the plot of course ;-). I think
>
> this can only be done by modifying partvelvec so that it returns
>
> "something" that can be used to plot a legend afterwards. Like:
>
>
>
> cgImage, myImage
>
> partvelvec, vx, vy, px, py, /OVER, LEGEND_struc=legend ;output
>
> partvelvec_legend, legend, POSITION=poslegend, etc.
>
>
>
> Anyways, if someone did this already and is willing to share I would be
>
> very thankful. If not, I'm open to suggestions on how to do this the
>
> right way ;)
>
>
>
> Cheers,
>
>
>
> Fab
|
|
|
|
comp.lang.idl-pvwave archive
Members
Search
Help
Login
Home
