[GRASS-user] how to query a raster value

[Markus Neteler]

On Tue, Nov 27, 2012 at 4:21 PM, 侯伟 <houw11 at lzu.edu.cn> wrote:
>
> in map display has a query button, i want to query a image value in a point
> but get the below:
>
> 489701.0583783784|4273345.954594594||*|
>
> no value are displayed.  i think in grass there are category and cell can be
> rater, does above are one type of this.

To me it looks as if the position is in a NO DATA area ("*").

> how can i change the type and query the value?

Please double check the coordinates.

Markus