add: conversion class from csv array strings to float[]. Used by Nicola in...

add: conversion class from csv array strings to float[]. Used by Nicola in Matlab to quickly convert the peak data from the metabolomics database as the native Matlab solution has performance problems.

SVN: 11776

rtd_yeastx/source/java/Convert.java

+/*
+ * Copyright 2009 ETH Zuerich, CISD
+ *
+ * Licensed 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.
+ */
+
+/**
+ * A class featuring a conversion of CSV strings to float arrays. We keep it in the default package
+ * even when this is deprecated because it is used from Matlab and not having to type any package
+ * name is preferred by Matlab users.
+ * 
+ * @author Bernd Rinn
+ */
+public class Convert
+{
+    private static int countMatches(String str, String sub)
+    {
+        if (str == null || str.length() == 0 || sub == null || sub.length() == 0)
+        {
+            return 0;
+        }
+        int count = 0;
+        int idx = 0;
+        while ((idx = str.indexOf(sub, idx)) != -1)
+        {
+            count++;
+            idx += sub.length();
+        }
+        return count;
+    }
+
+    /**
+     * Converts the given <var>csvList</var> string, which is expected to contain a comma-separated
+     * list of values, into a <code>float[]</code>.
+     */
+    public static float[] csvToFloatArray(String csvList)
+    {
+        final float[] floatArr = new float[countMatches(csvList, ",") + 1];
+        int idxStart = 0;
+        int idxEnd = 0;
+        int slen = csvList.length();
+        for (int i = 0; i < floatArr.length; ++i)
+        {
+            while (idxEnd < slen && csvList.charAt(idxEnd) != ',')
+            {
+                ++idxEnd;
+            }
+            floatArr[i] = Float.parseFloat(csvList.substring(idxStart, idxEnd));
+            idxStart = idxEnd + 1;
+            idxEnd = idxStart;
+        }
+        return floatArr;
+    }
+
+}