ee.ConfusionMatrix

  • Creates a confusion matrix from a 2D array of integers, where rows represent actual values and columns represent predicted values.

  • The order parameter can be used to specify custom class labels for the rows and columns of the matrix.

  • If order is not specified, it defaults to a 0-based sequence incrementing by 1.

  • The ee.ConfusionMatrix object provides methods for analyzing the confusion matrix.

 Creates a confusion matrix. Axis 0 (the rows) of the matrix correspond to the actual values, and Axis 1 (the columns) to the predicted values.

UsageReturns
ee.ConfusionMatrix(array, order)ConfusionMatrix
ArgumentTypeDetails
arrayObjectA square, 2D array of integers, representing the confusion matrix. Note that unlike the ee.Array constructor, this argument cannot take a list.
orderList, default: nullThe row and column size and order, for non-contiguous or non-zero based matrices.

Examples

Code Editor (JavaScript)

// A confusion matrix. Rows correspond to actual values, columns to
// predicted values.
var array = ee.Array([[32, 0, 0,  0,  1, 0],
                      [ 0, 5, 0,  0,  1, 0],
                      [ 0, 0, 1,  3,  0, 0],
                      [ 0, 1, 4, 26,  8, 0],
                      [ 0, 0, 0,  7, 15, 0],
                      [ 0, 0, 0,  1,  0, 5]]);
print('Constructed confusion matrix',
      ee.ConfusionMatrix(array));

// The "order" parameter refers to row and column class labels. When
// unspecified, the class labels are assumed to be a 0-based sequence
// incrementing by 1 with a length equal to row/column size.
print('Default row/column labels (unspecified "order" parameter)',
      ee.ConfusionMatrix({array: array, order: null}).order());

// Set the "order" parameter when custom class label integers are required. The
// list of integer value labels should correspond to the matrix axes left to
// right / top to bottom.
var order = [11, 22, 42, 52, 71, 81];
print('Specified row/column labels (specified "order" parameter)',
      ee.ConfusionMatrix({array: array, order: order}).order());

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)

from pprint import pprint

# A confusion matrix. Rows correspond to actual values, columns to
# predicted values.
array = ee.Array([[32, 0, 0,  0,  1, 0],
                  [ 0, 5, 0,  0,  1, 0],
                  [ 0, 0, 1,  3,  0, 0],
                  [ 0, 1, 4, 26,  8, 0],
                  [ 0, 0, 0,  7, 15, 0],
                  [ 0, 0, 0,  1,  0, 5]])
print('Constructed confusion matrix:')
pprint(ee.ConfusionMatrix(array).getInfo())

# The "order" parameter refers to row and column class labels. When
# unspecified, the class labels are assumed to be a 0-based sequence
# incrementing by 1 with a length equal to row/column size.
print('Default row/column labels (unspecified "order" parameter):',
      ee.ConfusionMatrix(array, None).order().getInfo())

# Set the "order" parameter when custom class label integers are required. The
# list of integer value labels should correspond to the matrix axes left to
# right / top to bottom.
order = [11, 22, 42, 52, 71, 81]
print('Specified row/column labels (specified "order" parameter):',
      ee.ConfusionMatrix(array, order).order().getInfo())