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NetFlatten[net]

collapses nested NetChain and NetGraph objects within net.

NetFlatten[net,n]

collapses up to nesting level n.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
Scope  
Properties & Relations  
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NetFlatten

NetFlatten[net]

collapses nested NetChain and NetGraph objects within net.

NetFlatten[net,n]

collapses up to nesting level n.

Details and Options

Examples

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Basic Examples  (2)

Flatten nested chains:

Wolfram Language code: chain = NetChain[{2, NetChain[{3, Ramp}], 4}]
Wolfram Language code: NetFlatten[chain]

Flatten nested graphs:

Wolfram Language code: graph = NetGraph[{4, Tanh, NetGraph[{2, Tanh, Ramp, CatenateLayer[]}, {1 -> {2, 3} -> 4}], ThreadingLayer[Times]}, {1 -> 2, {2, 3} -> 4}]
Wolfram Language code: NetFlatten[graph]

Scope  (3)

Turn a NetChain with nested NetGraph into a unique NetGraph:

Wolfram Language code: graphinchain = NetChain[{2, NetGraph[{Tanh, Ramp, CatenateLayer[]}, {{1, 2} -> 3}], 8}]
Wolfram Language code: NetFlatten[graphinchain]

Collapse nested NetChain and NetGraph up to level 1:

Wolfram Language code: capsulenet = NetModel["CapsNet Trained on MNIST Data"]
Wolfram Language code: NetFlatten[capsulenet, 1]

Turn a flat NetGraph into a NetChain:

Wolfram Language code: flatgraph = NetGraph[{2, Tanh, NetGraph[{3, SoftmaxLayer[]}, {1 -> 2}]}, {1 -> 2 -> 3}]
Wolfram Language code: NetFlatten[flatgraph]

Properties & Relations  (3)

NetFlatten flattens nested nets, including within operators.

Construct an operator that contains nested chains:

Wolfram Language code: map = NetMapOperator[NetChain[{1, NetChain[{Ramp, 2}]}]]

The inner net of the NetMapOperator has been flattened:

Wolfram Language code: flattened = NetFlatten[map]

NetFlatten yields a NetChain for a NetGraph that is fully flat:

Wolfram Language code: flatgraph = NetGraph[{2, Tanh, NetGraph[{3, SoftmaxLayer[]}, {1 -> 2}]}, {1 -> 2 -> 3}]
Wolfram Language code: NetFlatten[flatgraph]

NetFlatten yields a NetGraph for a NetChain that contains a nested NetGraph:

Wolfram Language code: graphinchain = NetChain[{2, NetGraph[{Tanh, Ramp, CatenateLayer[]}, {{1, 2} -> 3}], 8}]
Wolfram Language code: NetFlatten[graphinchain]
Wolfram Research (2018), NetFlatten, Wolfram Language function, https://reference.wolfram.com/language/ref/NetFlatten.html (updated 2019).

Text

Wolfram Research (2018), NetFlatten, Wolfram Language function, https://reference.wolfram.com/language/ref/NetFlatten.html (updated 2019).

CMS

Wolfram Language. 2018. "NetFlatten." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2019. https://reference.wolfram.com/language/ref/NetFlatten.html.

APA

Wolfram Language. (2018). NetFlatten. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/NetFlatten.html

BibTeX

@misc{reference.wolfram_2026_netflatten, author="Wolfram Research", title="{NetFlatten}", year="2019", howpublished="\url{https://reference.wolfram.com/language/ref/NetFlatten.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_netflatten, organization={Wolfram Research}, title={NetFlatten}, year={2019}, url={https://reference.wolfram.com/language/ref/NetFlatten.html}, note=[Accessed: 13-June-2026]}