ee.Array.slice

AI-generated Key Takeaways

• The Array.slice() method creates a subarray by extracting elements along a specified axis based on start, end, and step parameters.

• The resulting subarray retains the same dimensions as the original array, with the length along the sliced axis determined by the slicing parameters.

• Negative values for start and end can be used to specify positions relative to the end of the array.

• The step parameter defines the interval between selected slices along the axis and must be a positive integer.

Creates a subarray by slicing out each position along the given axis from the 'start' (inclusive) to 'end' (exclusive) by increments of 'step'. The result will have as many dimensions as the input, and the same length in all directions except the slicing axis, where the length will be the number of positions from 'start' to 'end' by 'step' that are in range of the input array's length along 'axis'. This means the result can be length 0 along the given axis if start=end, or if the start or end values are entirely out of range.

Usage	Returns
Array.slice(axis, start, end, step)	Array

Argument	Type	Details
this: array	Array	Array to slice.
axis	Integer, default: 0	The axis to slice on.
start	Integer, default: 0	The coordinate of the first slice (inclusive) along 'axis'. Negative numbers are used to position the start of slicing relative to the end of the array, where -1 starts at the last position on the axis, -2 starts at the next to last position, etc.
end	Integer, default: null	The coordinate (exclusive) at which to stop taking slices. By default this will be the length of the given axis. Negative numbers are used to position the end of slicing relative to the end of the array, where -1 will exclude the last position, -2 will exclude the last two positions, etc.
step	Integer, default: 1	The separation between slices along 'axis'; a slice will be taken at each whole multiple of 'step' from 'start' (inclusive) to 'end' (exclusive). Must be positive.

Examples

Code Editor (JavaScript)

var array1x6 = ee.Array([1, 2, 3, 4, 5, 6]);
print(array1x6.slice());  // [1,2,3,4,5,6]
print(array1x6.slice(0));  // [1,2,3,4,5,6]
print(array1x6.slice(0, 0, 6, 1));  // [1,2,3,4,5,6]
print(array1x6.slice(0, 0, 10, 1));  // [1,2,3,4,5,6]

print(array1x6.slice(0, 2));  // [3,4,5,6]
print(array1x6.slice(0, 5));  // [6]
print(array1x6.slice(0, 6));  // []
print(array1x6.slice(0, 0, 2));  // [1,2]
print(array1x6.slice(0, 0, 0));  // []

// Negative start and end.
print(array1x6.slice(0, 0, -3));  // [1,2,3]
print(array1x6.slice(0, -2, 6));  // [5,6]

print(array1x6.slice(0, 0, 6, 2));  // [1,3,5]
print(array1x6.slice(0, 0, 6, 3));  // [1,4]
print(array1x6.slice(0, 0, 6, 4));  // [1,5]
print(array1x6.slice(0, 0, 6, 6));  // [1]

print(array1x6.slice(0, 2, 6, 2));  // [3,5]

var array3x2 = ee.Array([[1, 2], [3, 4], [5, 6]]);
print(array3x2.slice());  // [[1,2],[3,4],[5,6]]
print(array3x2.slice(0));  // [[1,2],[3,4],[5,6]]
print(array3x2.slice(0, 0));  // [[1,2],[3,4],[5,6]]
print(array3x2.slice(0, 0, 1));  // [[1,2]]
print(array3x2.slice(0, 0, 2));  // [[1,2],[3,4]]
print(array3x2.slice(0, 0, 3, 1));  // [[1,2],[3,4],[5,6]]
print(array3x2.slice(0, 0, 3, 2));  // [[1,2],[5,6]]
print(array3x2.slice(0, 1, 3, 2));  // [[3,4]]
print(array3x2.slice(0, 0, 3, 3));  // [[1,2]]

print(array3x2.slice(1));  // [[1,2],[3,4],[5,6]]
print(array3x2.slice(1, 1));  // [[2],[4],[6]]
print(array3x2.slice(1, 0, 1));  // [[1],[3],[5]]

var empty = ee.Array([], ee.PixelType.int8());
print(empty.slice());  // []
print(empty.slice(0));  // []
print(empty.slice(0, 0, 0, 1));  // []

Python setup

See the Python Environment page for information on the Python API and using geemap for interactive development.

import ee
import geemap.core as geemap

Colab (Python)

array1x6 = ee.Array([1, 2, 3, 4, 5, 6])
display(array1x6.slice())  # [1, 2, 3, 4, 5, 6]
display(array1x6.slice(0))  # [1, 2, 3, 4, 5, 6]
display(array1x6.slice(0, 0, 6, 1))  # [1, 2, 3, 4, 5, 6]
display(array1x6.slice(0, 0, 10, 1))  # [1, 2, 3, 4, 5, 6]

display(array1x6.slice(0, 2))  # [3, 4, 5, 6]
display(array1x6.slice(0, 5))  # [6]
display(array1x6.slice(0, 6))  # []
display(array1x6.slice(0, 0, 2))  # [1, 2]
display(array1x6.slice(0, 0, 0))  # []

# Negative start and end.
display(array1x6.slice(0, 0, -3))  # [1, 2, 3]
display(array1x6.slice(0, -2, 6))  # [5, 6]

display(array1x6.slice(0, 0, 6, 2))  # [1, 3, 5]
display(array1x6.slice(0, 0, 6, 3))  # [1, 4]
display(array1x6.slice(0, 0, 6, 4))  # [1, 5]
display(array1x6.slice(0, 0, 6, 6))  # [1]

display(array1x6.slice(0, 2, 6, 2))  # [3, 5]

array3x2 = ee.Array([[1, 2], [3, 4], [5, 6]])
display(array3x2.slice())  # [[1, 2], [3, 4], [5, 6]]
display(array3x2.slice(0))  # [[1, 2], [3, 4], [5, 6]]
display(array3x2.slice(0, 0))  # [[1, 2],[3, 4],[5, 6]]
display(array3x2.slice(0, 0, 1))  # [[1, 2]]
display(array3x2.slice(0, 0, 2))  # [[1, 2], [3, 4]]
display(array3x2.slice(0, 0, 3, 1))  # [[1, 2], [3, 4], [5, 6]]
display(array3x2.slice(0, 0, 3, 2))  # [[1, 2], [5, 6]]
display(array3x2.slice(0, 1, 3, 2))  # [[3, 4]]
display(array3x2.slice(0, 0, 3, 3))  # [[1, 2]]

display(array3x2.slice(1))  # [[1, 2], [3, 4], [5, 6]]
display(array3x2.slice(1, 1))  # [[2], [4], [6]]
display(array3x2.slice(1, 0, 1))  # [[1], [3], [5]]

empty = ee.Array([], ee.PixelType.int8())
display(empty.slice())  # []
display(empty.slice(0))  # []
display(empty.slice(0, 0, 0, 1))  # []