Wolfram Language & System Documentation Center

ContrastiveLossLayer[]

represents a loss layer that computes a loss based on a distance metric and a target that specifies whether the distance should be minimized or maximized.

ContrastiveLossLayer[margin]

specifies a distance above which the loss is zero for True targets.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Applications  
See Also
Tech Notes
Related Guides
History
Cite this Page

ContrastiveLossLayer

ContrastiveLossLayer[]

represents a loss layer that computes a loss based on a distance metric and a target that specifies whether the distance should be minimized or maximized.

ContrastiveLossLayer[margin]

specifies a distance above which the loss is zero for True targets.

Details and Options

Examples

open all close all

Basic Examples  (2)

Create a ContrastiveLossLayer with a given margin:

Create a ContrastiveLossLayer:

Apply it to some data:

If the target is True, the loss is nonzero only when the input distance is less than the default margin of 0.5:

If the target is False, the loss is proportional to the input distance:

Applications  (1)

Train a multilayer perceptron to embed a synthetic dataset based only on its topology. First, create the training data on a spiral-like manifold that is dense in the plane:

Create the perceptron:

Create a loss network to measure the performance of the embedding:

Create a generator that will sample pairs of points and associate them with True if their parameterization on the manifold differs by more than Pi:

Train the network, using a generator to sample pairs of points, and classify them as the same if their original parameterization was close:

Extract the embedding from the net:

Plot the 1D embedding learned by the net as a color map:

Wolfram Research (2017), ContrastiveLossLayer, Wolfram Language function, https://reference.wolfram.com/language/ref/ContrastiveLossLayer.html.

Text

Wolfram Research (2017), ContrastiveLossLayer, Wolfram Language function, https://reference.wolfram.com/language/ref/ContrastiveLossLayer.html.

CMS

Wolfram Language. 2017. "ContrastiveLossLayer." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/ContrastiveLossLayer.html.

APA

Wolfram Language. (2017). ContrastiveLossLayer. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ContrastiveLossLayer.html

BibTeX

@misc{reference.wolfram_2025_contrastivelosslayer, author="Wolfram Research", title="{ContrastiveLossLayer}", year="2017", howpublished="\url{https://reference.wolfram.com/language/ref/ContrastiveLossLayer.html}", note=[Accessed: 01-December-2025]}

BibLaTeX

@online{reference.wolfram_2025_contrastivelosslayer, organization={Wolfram Research}, title={ContrastiveLossLayer}, year={2017}, url={https://reference.wolfram.com/language/ref/ContrastiveLossLayer.html}, note=[Accessed: 01-December-2025]}