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diff --git a/src/main/java/org/apache/commons/math/util/CompositeFormat.java b/src/main/java/org/apache/commons/math/util/CompositeFormat.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.math.util;
+
+import java.text.FieldPosition;
+import java.text.Format;
+import java.text.NumberFormat;
+import java.text.ParsePosition;
+import java.util.Locale;
+
+/**
+ * Base class for formatters of composite objects (complex numbers, vectors ...).
+ *
+ * @version $Revision: 1042376 $ $Date: 2010-12-05 16:54:55 +0100 (dim. 05 déc. 2010) $
+ */
+public abstract class CompositeFormat extends Format {
+
+    /** Serializable version identifier. */
+    private static final long serialVersionUID = 5358685519349262494L;
+
+    /**
+     * Create a default number format.  The default number format is based on
+     * {@link NumberFormat#getInstance()} with the only customizing that the
+     * maximum number of fraction digits is set to 2.
+     * @return the default number format.
+     */
+    protected static NumberFormat getDefaultNumberFormat() {
+        return getDefaultNumberFormat(Locale.getDefault());
+    }
+
+    /**
+     * Create a default number format.  The default number format is based on
+     * {@link NumberFormat#getInstance(java.util.Locale)} with the only
+     * customizing that the maximum number of fraction digits is set to 2.
+     * @param locale the specific locale used by the format.
+     * @return the default number format specific to the given locale.
+     */
+    protected static NumberFormat getDefaultNumberFormat(final Locale locale) {
+        final NumberFormat nf = NumberFormat.getInstance(locale);
+        nf.setMaximumFractionDigits(2);
+        return nf;
+    }
+
+    /**
+     * Parses <code>source</code> until a non-whitespace character is found.
+     *
+     * @param source the string to parse
+     * @param pos input/ouput parsing parameter.  On output, <code>pos</code>
+     *        holds the index of the next non-whitespace character.
+     */
+    protected void parseAndIgnoreWhitespace(final String source,
+                                            final ParsePosition pos) {
+        parseNextCharacter(source, pos);
+        pos.setIndex(pos.getIndex() - 1);
+    }
+
+    /**
+     * Parses <code>source</code> until a non-whitespace character is found.
+     *
+     * @param source the string to parse
+     * @param pos input/ouput parsing parameter.
+     * @return the first non-whitespace character.
+     */
+    protected char parseNextCharacter(final String source,
+                                      final ParsePosition pos) {
+         int index = pos.getIndex();
+         final int n = source.length();
+         char ret = 0;
+
+         if (index < n) {
+             char c;
+             do {
+                 c = source.charAt(index++);
+             } while (Character.isWhitespace(c) && index < n);
+             pos.setIndex(index);
+
+             if (index < n) {
+                 ret = c;
+             }
+         }
+
+         return ret;
+    }
+
+    /**
+     * Parses <code>source</code> for special double values.  These values
+     * include Double.NaN, Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY.
+     *
+     * @param source the string to parse
+     * @param value the special value to parse.
+     * @param pos input/ouput parsing parameter.
+     * @return the special number.
+     */
+    private Number parseNumber(final String source, final double value,
+                               final ParsePosition pos) {
+        Number ret = null;
+
+        StringBuilder sb = new StringBuilder();
+        sb.append('(');
+        sb.append(value);
+        sb.append(')');
+
+        final int n = sb.length();
+        final int startIndex = pos.getIndex();
+        final int endIndex = startIndex + n;
+        if (endIndex < source.length()) {
+            if (source.substring(startIndex, endIndex).compareTo(sb.toString()) == 0) {
+                ret = Double.valueOf(value);
+                pos.setIndex(endIndex);
+            }
+        }
+
+        return ret;
+    }
+
+    /**
+     * Parses <code>source</code> for a number.  This method can parse normal,
+     * numeric values as well as special values.  These special values include
+     * Double.NaN, Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY.
+     *
+     * @param source the string to parse
+     * @param format the number format used to parse normal, numeric values.
+     * @param pos input/ouput parsing parameter.
+     * @return the parsed number.
+     */
+    protected Number parseNumber(final String source, final NumberFormat format,
+                                 final ParsePosition pos) {
+        final int startIndex = pos.getIndex();
+        Number number = format.parse(source, pos);
+        final int endIndex = pos.getIndex();
+
+        // check for error parsing number
+        if (startIndex == endIndex) {
+            // try parsing special numbers
+            final double[] special = {
+                Double.NaN, Double.POSITIVE_INFINITY, Double.NEGATIVE_INFINITY
+            };
+            for (int i = 0; i < special.length; ++i) {
+                number = parseNumber(source, special[i], pos);
+                if (number != null) {
+                    break;
+                }
+            }
+        }
+
+        return number;
+    }
+
+    /**
+     * Parse <code>source</code> for an expected fixed string.
+     * @param source the string to parse
+     * @param expected expected string
+     * @param pos input/ouput parsing parameter.
+     * @return true if the expected string was there
+     */
+    protected boolean parseFixedstring(final String source, final String expected,
+                                       final ParsePosition pos) {
+
+        final int startIndex = pos.getIndex();
+        final int endIndex = startIndex + expected.length();
+        if ((startIndex >= source.length()) ||
+            (endIndex > source.length()) ||
+            (source.substring(startIndex, endIndex).compareTo(expected) != 0)) {
+            // set index back to start, error index should be the start index
+            pos.setIndex(startIndex);
+            pos.setErrorIndex(startIndex);
+            return false;
+        }
+
+        // the string was here
+        pos.setIndex(endIndex);
+        return true;
+
+    }
+
+    /**
+     * Formats a double value to produce a string.  In general, the value is
+     * formatted using the formatting rules of <code>format</code>.  There are
+     * three exceptions to this:
+     * <ol>
+     * <li>NaN is formatted as '(NaN)'</li>
+     * <li>Positive infinity is formatted as '(Infinity)'</li>
+     * <li>Negative infinity is formatted as '(-Infinity)'</li>
+     * </ol>
+     *
+     * @param value the double to format.
+     * @param format the format used.
+     * @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.
+     */
+    protected StringBuffer formatDouble(final double value, final NumberFormat format,
+                                        final StringBuffer toAppendTo,
+                                        final FieldPosition pos) {
+        if( Double.isNaN(value) || Double.isInfinite(value) ) {
+            toAppendTo.append('(');
+            toAppendTo.append(value);
+            toAppendTo.append(')');
+        } else {
+            format.format(value, toAppendTo, pos);
+        }
+        return toAppendTo;
+    }
+
+}