---
title: "Step"
method: POST
path: "/method/enautilus/step"
---

# Step

`POST /method/enautilus/step`

.

## Request body

- EnautilusStepRequest — Model of the request to the E-NAUTILUS method.
  - `problem_id` integer, required
  - `session_id` integer, nullable
  - `parent_state_id` integer, nullable
  - `representative_solutions_id` integer, nullable
  - `current_iteration` integer, required — The number of the current iteration.
  - `iterations_left` integer, required — The number of iterations left.
  - `selected_point` object, required — The selected intermediate point. If first iteration, set this to be the (approximated) nadir point.
  - `reachable_point_indices` integer[], required — The indices indicating the point on the non-dominated set that are reachable from the currently selected point.
  - `number_of_intermediate_points` integer, required — The number of intermediate points to be generated.

## Response `200`

Successful Response

- ENautilusState — E-NAUTILUS: one stepping iteration.
  - `id` integer, nullable
  - `non_dominated_solutions_id` integer, nullable
  - `current_iteration` integer, required
  - `iterations_left` integer, required
  - `selected_point` object, nullable
  - `reachable_point_indices` integer[]
  - `number_of_intermediate_points` integer, required
  - `enautilus_results` ENautilusResult, required — The result of an iteration of the E-NAUTILUS method.
    - `current_iteration` integer, required — Number of the current iteration.
    - `iterations_left` integer, required — Number of iterations left.
    - `intermediate_points` object[], required — New intermediate points
    - `reachable_best_bounds` object[], required — Best bounds of the objective function values reachable from each intermediate point.
    - `reachable_worst_bounds` object[], required — Worst bounds of the objective function values reachable from each intermediate point.
    - `closeness_measures` number[], required — Closeness measures of each intermediate point.
    - `reachable_point_indices` array[], required — Indices of the reachable points from each intermediate point.
      - integer[]

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/industrial-optimization-group/apis/desdeo-fast-api.md) · [All operations](https://skmtc.net/industrial-optimization-group/apis/desdeo-fast-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/industrial-optimization-group/desdeo-fast-api/versions/c24fa4e23380/schema)