php-mapscript tile indexing

[Palanisamy, Giri]

Hi,

I am able to customize the GMap php-rosa sample app. I have the
following layer in my .map file, I am using TILEINDEX for 8km and 1km
resolution and for the top level 50 km I am using tif image. In by JBox
I used to call this layer by the GROUP " MOD12Q1" and it worked, now in
the php application how do I call this group? Is there similar method
call like getlayerbyname() for LAYER GROUP?

 $poLayer = $gpoMap->getlayerbyname("IGBP_MOD12Q1");
 $poLayer->set("status", 1);

Returns
Warning: getLayerByName failed for : IGBP_MOD12Q1 in
f:\Inetpub\wwwroot\gmap\htdocs\gmap75.inc.php on line 116

Any suggestion would be highly appreciated Thanks!
Giri

Here is my layer snippet from the .map file

LAYER
  NAME IGBP_50k
  GROUP IGBP_MOD12Q1
  TYPE RASTER
  DATA LL_SDS01GR50.tif
  STATUS ON
  MINSCALE 1490000
  MAXSCALE 190000000
  #MAXSCALE 10000
  PROJECTION
        "proj=longlat"
        "ellps=GRS80"
        "no_defs"  	
  END
END
LAYER
  NAME IGBP_8K
  GROUP IGBP_MOD12Q1
  TYPE RASTER
  STATUS ON
  TILEINDEX "modis_8km"
  TILEITEM "Location"
  MINSCALE 29000000
  MAXSCALE 150000000
  PROJECTION
        "proj=longlat"
        "ellps=GRS80"
        "no_defs"
        "proj=eqc"  	
  END

END
LAYER
  NAME IGBP_1K
  GROUP IGBP_MOD12Q1
  TYPE RASTER
  STATUS ON
  TILEINDEX "modis_1km"
  TILEITEM "Location"
  #MINSCALE 8000000
  MAXSCALE 30000000
  PROJECTION
        "proj=longlat"
        "ellps=GRS80"
        "no_defs"
        "proj=eqc"  	
  END

END

Giri