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diff --git a/src/main/java/org/apache/commons/math3/ode/FieldODEState.java b/src/main/java/org/apache/commons/math3/ode/FieldODEState.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.math3.ode;
+
+import org.apache.commons.math3.Field;
+import org.apache.commons.math3.RealFieldElement;
+import org.apache.commons.math3.util.MathArrays;
+
+/**
+ * Container for time, main and secondary state vectors.
+ *
+ * @see FirstOrderFieldDifferentialEquations
+ * @see FieldSecondaryEquations
+ * @see FirstOrderFieldIntegrator
+ * @see FieldODEStateAndDerivative
+ * @param <T> the type of the field elements
+ * @since 3.6
+ */
+public class FieldODEState<T extends RealFieldElement<T>> {
+
+    /** Time. */
+    private final T time;
+
+    /** Main state at time. */
+    private final T[] state;
+
+    /** Secondary state at time. */
+    private final T[][] secondaryState;
+
+    /**
+     * Simple constructor.
+     *
+     * <p>Calling this constructor is equivalent to call {@link #FieldODEState(RealFieldElement,
+     * RealFieldElement[], RealFieldElement[][]) FieldODEState(time, state, null)}.
+     *
+     * @param time time
+     * @param state state at time
+     */
+    public FieldODEState(T time, T[] state) {
+        this(time, state, null);
+    }
+
+    /**
+     * Simple constructor.
+     *
+     * @param time time
+     * @param state state at time
+     * @param secondaryState state at time (may be null)
+     */
+    public FieldODEState(T time, T[] state, T[][] secondaryState) {
+        this.time = time;
+        this.state = state.clone();
+        this.secondaryState = copy(time.getField(), secondaryState);
+    }
+
+    /**
+     * Copy a two-dimensions array.
+     *
+     * @param field field to which elements belong
+     * @param original original array (may be null)
+     * @return copied array or null if original array was null
+     */
+    protected T[][] copy(final Field<T> field, final T[][] original) {
+
+        // special handling of null arrays
+        if (original == null) {
+            return null;
+        }
+
+        // allocate the array
+        final T[][] copied = MathArrays.buildArray(field, original.length, -1);
+
+        // copy content
+        for (int i = 0; i < original.length; ++i) {
+            copied[i] = original[i].clone();
+        }
+
+        return copied;
+    }
+
+    /**
+     * Get time.
+     *
+     * @return time
+     */
+    public T getTime() {
+        return time;
+    }
+
+    /**
+     * Get main state dimension.
+     *
+     * @return main state dimension
+     */
+    public int getStateDimension() {
+        return state.length;
+    }
+
+    /**
+     * Get main state at time.
+     *
+     * @return main state at time
+     */
+    public T[] getState() {
+        return state.clone();
+    }
+
+    /**
+     * Get the number of secondary states.
+     *
+     * @return number of secondary states.
+     */
+    public int getNumberOfSecondaryStates() {
+        return secondaryState == null ? 0 : secondaryState.length;
+    }
+
+    /**
+     * Get secondary state dimension.
+     *
+     * @param index index of the secondary set as returned by {@link
+     *     FieldExpandableODE#addSecondaryEquations(FieldSecondaryEquations)} (beware index 0
+     *     corresponds to main state, additional states start at 1)
+     * @return secondary state dimension
+     */
+    public int getSecondaryStateDimension(final int index) {
+        return index == 0 ? state.length : secondaryState[index - 1].length;
+    }
+
+    /**
+     * Get secondary state at time.
+     *
+     * @param index index of the secondary set as returned by {@link
+     *     FieldExpandableODE#addSecondaryEquations(FieldSecondaryEquations)} (beware index 0
+     *     corresponds to main state, additional states start at 1)
+     * @return secondary state at time
+     */
+    public T[] getSecondaryState(final int index) {
+        return index == 0 ? state.clone() : secondaryState[index - 1].clone();
+    }
+}