[GRASS-user] passing raster map to Python object

[Hamish]

Milton Cezar Ribeiro wrote:
> Thanks for your encourager's email.
> I started to play with numpy for other purposes,
> but I will give a look in deep for this.
>  
> If I get success I will be happy report it here.

it should work. one thing, be sure to translate NULL cells to numpy.nan,

e.g.

>>> import numpy as np
>>> x = np.array([[1, 2, 3], [4, 5, 6]], np.float64)
>>> x
array([[ 1.,  2.,  3.],
       [ 4.,  5.,  6.]])
>>> x[0,1]
2.0

>>> x[0,1] = np.nan
>>> x
array([[ 1.        ,         nan,  3.        ],
       [ 4.        ,  5.        ,  6.        ]])

see swig/python/examples/rasteraccess.py for reading raster row by row.



Hamish