Come affettare un array 2D in Python senza usare NumPy

Slice a Range of Values from Two-dimensional Numpy Arrays

Puoi anche usare un range per l'indice di riga e/o l'indice di colonna per affettare più elementi usando:

[start_row_index:end_row_index, start_column_index:end_column_index]

Ricorda che la struttura degli indici per entrambi i range di riga e colonna include il primo indice, ma non il secondo.

For example, you can use the index [0:1, 0:2] to select the elements in first row, first two columns.

1. # Slice first row, first two columns 
2. print(precip_2002_2013[0:1, 0:2]) 

1. [[1.07 0.44]] 

You can flip these index values to select elements in the first two rows, first column.

1. # Slice first two rows, first column 
2. print(precip_2002_2013[0:2, 0:1]) 

1. [[1.07] 
2. [0.27]] 

If you wanted to slice the second row, second to third columns, you would need to use the index[1:2, 1:3], which again identifies the ending index range but does not include it in the output.

1. # Slice 2nd row, 2nd and 3rd columns 
2. print(precip_2002_2013[1:2, 1:3]) 

1. [[1.13 1.72]]