numpy arrays

[Heli]

Thanks for your replies. I have a question in regard with my previous question. I have a file that contains x,y,z and a value for that coordinate on each line. Here I am giving an example of the file using a numpy array called f. 

f=np.array([[1,1,1,1],
            [1,1,2,2], 
            [1,1,3,3],
            [1,2,1,4],
            [1,2,2,5],
            [1,2,3,6],
            [1,3,1,7],
            [1,3,2,8],
            [1,3,3,9],
            [2,1,1,10],
            [2,1,2,11],
            [2,1,3,12],
            [2,2,1,13],
            [2,2,2,14],
            [2,2,3,15],
            [2,3,1,16],
            [2,3,2,17],
            [2,3,3,18],
            [3,1,1,19],
            [3,1,2,20],
            [3,1,3,21],
            [3,2,1,22],
            [3,2,2,23],
            [3,2,3,24],
            [3,3,1,25],
            [3,3,2,26],
            [3,3,3,27],
            ])

then after tranposing f, I get the x,y and z coordinates:
f_tranpose=f.T
x=np.sort(np.unique(f_tranpose[0]))
y=np.sort(np.unique(f_tranpose[1]))
z=np.sort(np.unique(f_tranpose[2]))

Then I will create a 3D array to put the values inside. The only way I see to do this is the following:
arr_size=x.size
val2=np.empty([3, 3,3])

for sub_arr in f:
    idx = (np.abs(x-sub_arr[0])).argmin()
    idy = (np.abs(y-sub_arr[1])).argmin()
    idz = (np.abs(z-sub_arr[2])).argmin()
    val2[idx,idy,idz]=sub_arr[3]

I know that in the example above I could simple reshape f_tranpose[3] to a three by three by three array, but in my real example the coordinates are not in order and the only way I see to do this is by looping over the whole file which takes a lot of time. 

I would appreciate any workarounds to make this quicker. 

Thanks,