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<font face="Arial">dear group,<br>
<br>
I need to plot the wind directions for stations with equally sized
arrows.<br>
<br>
My dataset contains the direction in degrees (0-360).<br>
<br>
I use the gxout=vector map which requires a u and a v vector component
(i.e. the vertical and horizontal vector component).<br>
<br>
u<br>
| /winddir<br>
| /<br>
| /<br>
|/___ v<br>
<br>
<br>
I calculate u as -sin(winddir * pi/180)<br>
</font><font face="Arial">I calculate v as -cos(winddir * pi/180)<br>
</font><br>
<font face="Arial">resulting in the display-command '
-8*(sin(winddir * 0.0175)) ; -8*(cos(</font><font face="Arial">winddir</font><font
face="Arial"> * 0.0175)) '<br>
(where 8 makes the size of the arrow, which usually represents
windspeed but here is desired to be constant)<br>
<br>
<br>
The direction of the arrows looks fine. <br>
But some maps have only tiny arrows and some maps have only longtailed
arrows. <br>
I cannot see a pattern. I have no mixed maps with tiny and large arrows.<br>
<br>
Should I change my formula, or the way I give the display command?<br>
<br>
thanks,<br>
Chris <br>
<br>
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