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diff --git a/src/main/java/org/apache/commons/math3/fraction/BigFractionFormat.java b/src/main/java/org/apache/commons/math3/fraction/BigFractionFormat.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.fraction;
+
+import org.apache.commons.math3.exception.MathIllegalArgumentException;
+import org.apache.commons.math3.exception.MathParseException;
+import org.apache.commons.math3.exception.util.LocalizedFormats;
+
+import java.io.Serializable;
+import java.math.BigInteger;
+import java.text.FieldPosition;
+import java.text.NumberFormat;
+import java.text.ParsePosition;
+import java.util.Locale;
+
+/**
+ * Formats a BigFraction number in proper format or improper format.
+ *
+ * <p>The number format for each of the whole number, numerator and, denominator can be configured.
+ *
+ * @since 2.0
+ */
+public class BigFractionFormat extends AbstractFormat implements Serializable {
+
+    /** Serializable version identifier */
+    private static final long serialVersionUID = -2932167925527338976L;
+
+    /**
+     * Create an improper formatting instance with the default number format for the numerator and
+     * denominator.
+     */
+    public BigFractionFormat() {}
+
+    /**
+     * Create an improper formatting instance with a custom number format for both the numerator and
+     * denominator.
+     *
+     * @param format the custom format for both the numerator and denominator.
+     */
+    public BigFractionFormat(final NumberFormat format) {
+        super(format);
+    }
+
+    /**
+     * Create an improper formatting instance with a custom number format for the numerator and a
+     * custom number format for the denominator.
+     *
+     * @param numeratorFormat the custom format for the numerator.
+     * @param denominatorFormat the custom format for the denominator.
+     */
+    public BigFractionFormat(
+            final NumberFormat numeratorFormat, final NumberFormat denominatorFormat) {
+        super(numeratorFormat, denominatorFormat);
+    }
+
+    /**
+     * Get the set of locales for which complex formats are available. This is the same set as the
+     * {@link NumberFormat} set.
+     *
+     * @return available complex format locales.
+     */
+    public static Locale[] getAvailableLocales() {
+        return NumberFormat.getAvailableLocales();
+    }
+
+    /**
+     * This static method calls formatBigFraction() on a default instance of BigFractionFormat.
+     *
+     * @param f BigFraction object to format
+     * @return A formatted BigFraction in proper form.
+     */
+    public static String formatBigFraction(final BigFraction f) {
+        return getImproperInstance().format(f);
+    }
+
+    /**
+     * Returns the default complex format for the current locale.
+     *
+     * @return the default complex format.
+     */
+    public static BigFractionFormat getImproperInstance() {
+        return getImproperInstance(Locale.getDefault());
+    }
+
+    /**
+     * Returns the default complex format for the given locale.
+     *
+     * @param locale the specific locale used by the format.
+     * @return the complex format specific to the given locale.
+     */
+    public static BigFractionFormat getImproperInstance(final Locale locale) {
+        return new BigFractionFormat(getDefaultNumberFormat(locale));
+    }
+
+    /**
+     * Returns the default complex format for the current locale.
+     *
+     * @return the default complex format.
+     */
+    public static BigFractionFormat getProperInstance() {
+        return getProperInstance(Locale.getDefault());
+    }
+
+    /**
+     * Returns the default complex format for the given locale.
+     *
+     * @param locale the specific locale used by the format.
+     * @return the complex format specific to the given locale.
+     */
+    public static BigFractionFormat getProperInstance(final Locale locale) {
+        return new ProperBigFractionFormat(getDefaultNumberFormat(locale));
+    }
+
+    /**
+     * Formats a {@link BigFraction} object to produce a string. The BigFraction is output in
+     * improper format.
+     *
+     * @param BigFraction the object to format.
+     * @param toAppendTo where the text is to be appended
+     * @param pos On input: an alignment field, if desired. On output: the offsets of the alignment
+     *     field
+     * @return the value passed in as toAppendTo.
+     */
+    public StringBuffer format(
+            final BigFraction BigFraction, final StringBuffer toAppendTo, final FieldPosition pos) {
+
+        pos.setBeginIndex(0);
+        pos.setEndIndex(0);
+
+        getNumeratorFormat().format(BigFraction.getNumerator(), toAppendTo, pos);
+        toAppendTo.append(" / ");
+        getDenominatorFormat().format(BigFraction.getDenominator(), toAppendTo, pos);
+
+        return toAppendTo;
+    }
+
+    /**
+     * Formats an object and appends the result to a StringBuffer. <code>obj</code> must be either a
+     * {@link BigFraction} object or a {@link BigInteger} object or a {@link Number} object. Any
+     * other type of object will result in an {@link IllegalArgumentException} being thrown.
+     *
+     * @param obj the object to format.
+     * @param toAppendTo where the text is to be appended
+     * @param pos On input: an alignment field, if desired. On output: the offsets of the alignment
+     *     field
+     * @return the value passed in as toAppendTo.
+     * @see java.text.Format#format(java.lang.Object, java.lang.StringBuffer,
+     *     java.text.FieldPosition)
+     * @throws MathIllegalArgumentException if <code>obj</code> is not a valid type.
+     */
+    @Override
+    public StringBuffer format(
+            final Object obj, final StringBuffer toAppendTo, final FieldPosition pos) {
+
+        final StringBuffer ret;
+        if (obj instanceof BigFraction) {
+            ret = format((BigFraction) obj, toAppendTo, pos);
+        } else if (obj instanceof BigInteger) {
+            ret = format(new BigFraction((BigInteger) obj), toAppendTo, pos);
+        } else if (obj instanceof Number) {
+            ret = format(new BigFraction(((Number) obj).doubleValue()), toAppendTo, pos);
+        } else {
+            throw new MathIllegalArgumentException(
+                    LocalizedFormats.CANNOT_FORMAT_OBJECT_TO_FRACTION);
+        }
+
+        return ret;
+    }
+
+    /**
+     * Parses a string to produce a {@link BigFraction} object.
+     *
+     * @param source the string to parse
+     * @return the parsed {@link BigFraction} object.
+     * @exception MathParseException if the beginning of the specified string cannot be parsed.
+     */
+    @Override
+    public BigFraction parse(final String source) throws MathParseException {
+        final ParsePosition parsePosition = new ParsePosition(0);
+        final BigFraction result = parse(source, parsePosition);
+        if (parsePosition.getIndex() == 0) {
+            throw new MathParseException(source, parsePosition.getErrorIndex(), BigFraction.class);
+        }
+        return result;
+    }
+
+    /**
+     * Parses a string to produce a {@link BigFraction} object. This method expects the string to be
+     * formatted as an improper BigFraction.
+     *
+     * @param source the string to parse
+     * @param pos input/output parsing parameter.
+     * @return the parsed {@link BigFraction} object.
+     */
+    @Override
+    public BigFraction parse(final String source, final ParsePosition pos) {
+        final int initialIndex = pos.getIndex();
+
+        // parse whitespace
+        parseAndIgnoreWhitespace(source, pos);
+
+        // parse numerator
+        final BigInteger num = parseNextBigInteger(source, pos);
+        if (num == null) {
+            // invalid integer number
+            // set index back to initial, error index should already be set
+            // character examined.
+            pos.setIndex(initialIndex);
+            return null;
+        }
+
+        // parse '/'
+        final int startIndex = pos.getIndex();
+        final char c = parseNextCharacter(source, pos);
+        switch (c) {
+            case 0:
+                // no '/'
+                // return num as a BigFraction
+                return new BigFraction(num);
+            case '/':
+                // found '/', continue parsing denominator
+                break;
+            default:
+                // invalid '/'
+                // set index back to initial, error index should be the last
+                // character examined.
+                pos.setIndex(initialIndex);
+                pos.setErrorIndex(startIndex);
+                return null;
+        }
+
+        // parse whitespace
+        parseAndIgnoreWhitespace(source, pos);
+
+        // parse denominator
+        final BigInteger den = parseNextBigInteger(source, pos);
+        if (den == null) {
+            // invalid integer number
+            // set index back to initial, error index should already be set
+            // character examined.
+            pos.setIndex(initialIndex);
+            return null;
+        }
+
+        return new BigFraction(num, den);
+    }
+
+    /**
+     * Parses a string to produce a <code>BigInteger</code>.
+     *
+     * @param source the string to parse
+     * @param pos input/output parsing parameter.
+     * @return a parsed <code>BigInteger</code> or null if string does not contain a BigInteger at
+     *     the specified position
+     */
+    protected BigInteger parseNextBigInteger(final String source, final ParsePosition pos) {
+
+        final int start = pos.getIndex();
+        int end = (source.charAt(start) == '-') ? (start + 1) : start;
+        while ((end < source.length()) && Character.isDigit(source.charAt(end))) {
+            ++end;
+        }
+
+        try {
+            BigInteger n = new BigInteger(source.substring(start, end));
+            pos.setIndex(end);
+            return n;
+        } catch (NumberFormatException nfe) {
+            pos.setErrorIndex(start);
+            return null;
+        }
+    }
+}