[Gdal-dev] ReadAsArray()

[Frank Warmerdam]

Gong, Shawn (Contractor) wrote:
> Hi list,
> 
> I have questions regarding ReadAsArray()
> 
> Here is the code:
> 
>     msi_array = gdal_dataset.ReadAsArray().astype(Numeric.Float32)
> 
> Q1: what is msi_array?  Is it a Numeric array?

Shawn,

Yes

> Q2: printing out “print msi_array” generates a three-dimensional array 
> (or list?)
> 
> [ [ [0 1 2 up to col] ... ... up to row] ... up to bands]
> 
> What function to call if I want to get a number of subarrays like:
> 
>         R = #1 band and 100x50 pixels
> 
>         G = #2 band and 100x50 pixels
> 
> I have used
> 
>     r = msi_array[0:row][0:col][int(r_band)-1]
> 
>     g = msi_array[0:row][0:col][int(g_band)-1]
> 
> b = msi_array[0:row][0:col][int(b_band)-1]

I believe you can just do:

  r = msi_array[r_band-1]
  g = msi_array[g_band-1]
  b = msi_array[b_band-1]

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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