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Stanford CoreNLP provides a set of natural language analysis tools which can take raw English language text input and give the base forms of words, their parts of speech, whether they are names of companies, people, etc., normalize dates, times, and numeric quantities, mark up the structure of sentences in terms of phrases and word dependencies, and indicate which noun phrases refer to the same entities. It provides the foundational building blocks for higher level text understanding applications.
package edu.stanford.nlp.util;
import edu.stanford.nlp.util.logging.Redwood;
import java.lang.reflect.Array;
import java.util.*;
import java.util.function.Function;
import java.util.function.Predicate;
/**
* Static utility methods for operating on arrays.
*
* Note: You can also find some methods for printing arrays that are tables in
* StringUtils. (Search for makeTextTable, etc.)
*
* @author Huy Nguyen ([email protected])
* @author Michel Galley ([email protected])
*/
public class ArrayUtils {
/** A logger for this class */
private static Redwood.RedwoodChannels log = Redwood.channels(ArrayUtils.class);
/**
* Should not be instantiated
*/
private ArrayUtils() {}
public static byte[] gapEncode(int[] orig) {
List encodedList = gapEncodeList(orig);
byte[] arr = new byte[encodedList.size()];
int i = 0;
for (byte b : encodedList) { arr[i++] = b; }
return arr;
}
public static List gapEncodeList(int[] orig) {
for (int i = 1; i < orig.length; i++) {
if (orig[i] < orig[i-1]) {
throw new IllegalArgumentException("Array must be sorted!");
}
}
List bytes = new ArrayList<>();
int index = 0;
int prevNum = 0;
byte currByte = 0 << 8;
for (int f : orig) {
String n = (f == prevNum ? "" : Integer.toString(f-prevNum, 2));
for (int ii = 0; ii < n.length(); ii++) {
if (index == 8) {
bytes.add(currByte);
currByte = 0 << 8;
index = 0;
}
currByte <<= 1;
currByte++;
index++;
}
if (index == 8) {
bytes.add(currByte);
currByte = 0 << 8;
index = 0;
}
currByte <<= 1;
index++;
for (int i = 1; i < n.length(); i++) {
if (index == 8) {
bytes.add(currByte);
currByte = 0 << 8;
index = 0;
}
currByte <<= 1;
if (n.charAt(i) == '1') {
currByte++;
}
index++;
}
prevNum = f;
}
while (index > 0 && index < 9) {
if (index == 8) {
bytes.add(currByte);
break;
}
currByte <<= 1;
currByte++;
index++;
}
return bytes;
}
public static int[] gapDecode(byte[] gapEncoded) {
return gapDecode(gapEncoded, 0, gapEncoded.length);
}
public static int[] gapDecode(byte[] gapEncoded, int startIndex, int endIndex) {
List ints = gapDecodeList(gapEncoded, startIndex, endIndex);
int[] arr = new int[ints.size()];
int index = 0;
for (int i : ints) { arr[index++] = i; }
return arr;
}
public static List gapDecodeList(byte[] gapEncoded) {
return gapDecodeList(gapEncoded, 0, gapEncoded.length);
}
public static List gapDecodeList(byte[] gapEncoded, int startIndex, int endIndex) {
boolean gettingSize = true;
int size = 0;
List ints = new ArrayList<>();
int gap = 0;
int prevNum = 0;
for (int i = startIndex; i < endIndex; i++) {
byte b = gapEncoded[i];
for (int index = 7; index >= 0; index--) {
boolean value = ((b >> index) & 1) == 1;
if (gettingSize) {
if (value) { size++; }
else {
if (size == 0) {
ints.add(prevNum);
} else if (size == 1) {
prevNum++;
ints.add(prevNum);
size = 0;
} else {
gettingSize = false;
gap = 1;
size--;
}
}
} else {
gap <<= 1;
if (value) { gap++; }
size--;
if (size == 0) {
prevNum += gap;
ints.add(prevNum);
gettingSize = true;
}
}
}
}
return ints;
}
public static byte[] deltaEncode(int[] orig) {
List encodedList = deltaEncodeList(orig);
byte[] arr = new byte[encodedList.size()];
int i = 0;
for (byte b : encodedList) { arr[i++] = b; }
return arr;
}
public static List deltaEncodeList(int[] orig) {
for (int i = 1; i < orig.length; i++) {
if (orig[i] < orig[i-1]) {
throw new IllegalArgumentException("Array must be sorted!");
}
}
List bytes = new ArrayList<>();
int index = 0;
int prevNum = 0;
byte currByte = 0 << 8;
for (int f : orig) {
String n = (f == prevNum ? "" : Integer.toString(f-prevNum, 2));
String n1 = (n.isEmpty() ? "" : Integer.toString(n.length(), 2));
for (int ii = 0; ii < n1.length(); ii++) {
if (index == 8) {
bytes.add(currByte);
currByte = 0 << 8;
index = 0;
}
currByte <<= 1;
currByte++;
index++;
}
if (index == 8) {
bytes.add(currByte);
currByte = 0 << 8;
index = 0;
}
currByte <<= 1;
index++;
for (int i = 1; i < n1.length(); i++) {
if (index == 8) {
bytes.add(currByte);
currByte = 0 << 8;
index = 0;
}
currByte <<= 1;
if (n1.charAt(i) == '1') {
currByte++;
}
index++;
}
for (int i = 1; i < n.length(); i++) {
if (index == 8) {
bytes.add(currByte);
currByte = 0 << 8;
index = 0;
}
currByte <<= 1;
if (n.charAt(i) == '1') {
currByte++;
}
index++;
}
prevNum = f;
}
while (index > 0 && index < 9) {
if (index == 8) {
bytes.add(currByte);
break;
}
currByte <<= 1;
currByte++;
index++;
}
return bytes;
}
public static int[] deltaDecode(byte[] deltaEncoded) {
return deltaDecode(deltaEncoded, 0, deltaEncoded.length);
}
public static int[] deltaDecode(byte[] deltaEncoded, int startIndex, int endIndex) {
List ints = deltaDecodeList(deltaEncoded);
int[] arr = new int[ints.size()];
int index = 0;
for (int i : ints) { arr[index++] = i; }
return arr;
}
public static List deltaDecodeList(byte[] deltaEncoded) {
return deltaDecodeList(deltaEncoded, 0, deltaEncoded.length);
}
public static List deltaDecodeList(byte[] deltaEncoded, int startIndex, int endIndex) {
boolean gettingSize1 = true;
boolean gettingSize2 = false;
int size1 = 0;
List ints = new ArrayList<>();
int gap = 0;
int size2 = 0;
int prevNum = 0;
for (int i = startIndex; i < endIndex; i++) {
byte b = deltaEncoded[i];
for (int index = 7; index >= 0; index--) {
boolean value = ((b >> index) & 1) == 1;
if (gettingSize1) {
if (value) { size1++; }
else {
if (size1 == 0) {
ints.add(prevNum);
} else if (size1 == 1) {
prevNum++;
ints.add(prevNum);
size1 = 0;
} else {
gettingSize1 = false;
gettingSize2 = true;
size2 = 1;
size1--;
}
}
} else if (gettingSize2) {
size2 <<= 1;
if (value) { size2++; }
size1--;
if (size1 == 0) {
gettingSize2 = false;
gap = 1;
size2--;
}
} else {
gap <<= 1;
if (value) { gap++; }
size2--;
if (size2 == 0) {
prevNum += gap;
ints.add(prevNum);
gettingSize1 = true;
}
}
}
}
return ints;
}
/** helper for gap encoding. */
private static byte[] bitSetToByteArray(BitSet bitSet) {
while (bitSet.length() % 8 != 0) { bitSet.set(bitSet.length(), true); }
byte[] array = new byte[bitSet.length()/8];
for (int i = 0; i < array.length; i++) {
int offset = i * 8;
int index = 0;
for (int j = 0; j < 8; j++) {
index <<= 1;
if (bitSet.get(offset+j)) { index++; }
}
array[i] = (byte)(index - 128);
}
return array;
}
/** helper for gap encoding. */
private static BitSet byteArrayToBitSet(byte[] array) {
BitSet bitSet = new BitSet();
int index = 0;
for (byte b : array) {
int b1 = ((int)b) + 128;
bitSet.set(index++, ((b1 >> 7) & 1) == 1);
bitSet.set(index++, ((b1 >> 6) & 1) == 1);
bitSet.set(index++, ((b1 >> 5) & 1) == 1);
bitSet.set(index++, ((b1 >> 4) & 1) == 1);
bitSet.set(index++, ((b1 >> 3) & 1) == 1);
bitSet.set(index++, ((b1 >> 2) & 1) == 1);
bitSet.set(index++, ((b1 >> 1) & 1) == 1);
bitSet.set(index++, (b1 & 1) == 1);
}
return bitSet;
}
// for (int i = 1; i < orig.length; i++) {
// if (orig[i] < orig[i-1]) { throw new RuntimeException("Array must be sorted!"); }
// StringBuilder bits = new StringBuilder();
// int prevNum = 0;
// for (int f : orig) {
// StringBuilder bits1 = new StringBuilder();
// log.info(f+"\t");
// String n = Integer.toString(f-prevNum, 2);
// String n1 = Integer.toString(n.length(), 2);
// for (int ii = 0; ii < n1.length(); ii++) {
// bits1.append("1");
// }
// bits1.append("0");
// bits1.append(n1.substring(1));
// bits1.append(n.substring(1));
// log.info(bits1+"\t");
// bits.append(bits1);
// prevNum = f;
// }
public static double[] flatten(double[][] array) {
int size = 0;
for (double[] a : array) {
size += a.length;
}
double[] newArray = new double[size];
int i = 0;
for (double[] a : array) {
for (double d : a) {
newArray[i++] = d;
}
}
return newArray;
}
public static double[][] to2D(double[] array, int dim1Size) {
int dim2Size = array.length/dim1Size;
return to2D(array, dim1Size, dim2Size);
}
public static double[][] to2D(double[] array, int dim1Size, int dim2Size) {
double[][] newArray = new double[dim1Size][dim2Size];
int k = 0;
for (int i = 0; i < newArray.length; i++) {
for (int j = 0; j < newArray[i].length; j++) {
newArray[i][j] = array[k++];
}
}
return newArray;
}
/**
* Removes the element at the specified index from the array, and returns
* a new array containing the remaining elements. If index is
* invalid, returns array unchanged.
*/
public static double[] removeAt(double[] array, int index) {
if (array == null) {
return null;
}
if (index < 0 || index >= array.length) {
return array;
}
double[] retVal = new double[array.length - 1];
for (int i = 0; i < array.length; i++) {
if (i < index) {
retVal[i] = array[i];
} else if (i > index) {
retVal[i - 1] = array[i];
}
}
return retVal;
}
/**
* Removes the element at the specified index from the array, and returns
* a new array containing the remaining elements. If index is
* invalid, returns array unchanged. Uses reflection to determine
* the type of the array and returns an array of the appropriate type.
*/
public static Object[] removeAt(Object[] array, int index) {
if (array == null) {
return null;
}
if (index < 0 || index >= array.length) {
return array;
}
Object[] retVal = (Object[]) Array.newInstance(array[0].getClass(), array.length - 1);
for (int i = 0; i < array.length; i++) {
if (i < index) {
retVal[i] = array[i];
} else if (i > index) {
retVal[i - 1] = array[i];
}
}
return retVal;
}
public static String toString(int[][] a) {
StringBuilder result = new StringBuilder("[");
for (int i = 0; i < a.length; i++) {
result.append(Arrays.toString(a[i]));
if(i < a.length-1)
result.append(',');
}
result.append(']');
return result.toString();
}
/**
* Tests two int[][] arrays for having equal contents.
* @return true iff for each i, equalContents(xs[i],ys[i]) is true
*/
public static boolean equalContents(int[][] xs, int[][] ys) {
if(xs ==null)
return ys == null;
if(ys == null)
return false;
if(xs.length != ys.length)
return false;
for(int i = xs.length-1; i >= 0; i--) {
if(! equalContents(xs[i],ys[i]))
return false;
}
return true;
}
/**
* Tests two double[][] arrays for having equal contents.
* @return true iff for each i, equals(xs[i],ys[i]) is true
*/
public static boolean equals(double[][] xs, double[][] ys) {
if(xs == null)
return ys == null;
if(ys == null)
return false;
if(xs.length != ys.length)
return false;
for(int i = xs.length-1; i >= 0; i--) {
if(!Arrays.equals(xs[i],ys[i]))
return false;
}
return true;
}
/**
* tests two int[] arrays for having equal contents
* @return true iff xs and ys have equal length, and for each i, xs[i]==ys[i]
*/
public static boolean equalContents(int[] xs, int[] ys) {
if(xs.length != ys.length)
return false;
for(int i = xs.length-1; i >= 0; i--) {
if(xs[i] != ys[i])
return false;
}
return true;
}
/**
* Tests two boolean[][] arrays for having equal contents.
* @return true iff for each i, Arrays.equals(xs[i],ys[i]) is true
*/
@SuppressWarnings("null")
public static boolean equals(boolean[][] xs, boolean[][] ys) {
if(xs == null && ys != null)
return false;
if(ys == null)
return false;
if(xs.length != ys.length)
return false;
for(int i = xs.length-1; i >= 0; i--) {
if(! Arrays.equals(xs[i],ys[i]))
return false;
}
return true;
}
/** Returns true iff object o equals (not ==) some element of array a. */
public static boolean contains(T[] a, T o) {
for (T item : a) {
if (item.equals(o)) return true;
}
return false;
}
// from stackoverflow
// http://stackoverflow.com/questions/80476/how-to-concatenate-two-arrays-in-java
/**
* Concatenates two arrays and returns the result
*/
public static T[] concatenate(T[] first, T[] second) {
T[] result = Arrays.copyOf(first, first.length + second.length);
System.arraycopy(second, 0, result, first.length, second.length);
return result;
}
/**
* Returns an array with only the elements accepted by filter
*
* Implementation notes: creates two arrays, calls filter
* once for each element, does not alter original
*/
public static T[] filter(T[] original, Predicate filter) {
T[] result = Arrays.copyOf(original, original.length); // avoids generic array creation compile error
int size = 0;
for (T value : original) {
if (filter.test(value)) {
result[size] = value;
size++;
}
}
if (size == original.length) {
return result;
}
return Arrays.copyOf(result, size);
}
/** Return a Set containing the same elements as the specified array.
*/
public static Set asSet(T[] a) {
return Generics.newHashSet(Arrays.asList(a));
}
/** Return an immutable Set containing the same elements as the specified
* array. Arrays with 0 or 1 elements are special cased to return the
* efficient small sets from the Collections class.
*/
public static Set asImmutableSet(T[] a) {
if (a.length == 0) {
return Collections.emptySet();
} else if (a.length == 1) {
return Collections.singleton(a[0]);
} else {
return Collections.unmodifiableSet(Generics.newHashSet(Arrays.asList(a)));
}
}
public static void fill(double[][] d, double val) {
for (double[] aD : d) {
Arrays.fill(aD, val);
}
}
public static void fill(double[][][] d, double val) {
for (double[][] aD : d) {
fill(aD, val);
}
}
public static void fill(double[][][][] d, double val) {
for (double[][][] aD : d) {
fill(aD, val);
}
}
public static void fill(boolean[][] d, boolean val) {
for (boolean[] aD : d) {
Arrays.fill(aD, val);
}
}
public static void fill(boolean[][][] d, boolean val) {
for (boolean[][] aD : d) {
fill(aD, val);
}
}
public static void fill(boolean[][][][] d, boolean val) {
for (boolean[][][] aD : d) {
fill(aD, val);
}
}
/**
* Casts to a double array
*/
public static double[] toDouble(float[] a) {
double[] d = new double[a.length];
for (int i = 0; i < a.length; i++) {
d[i] = a[i];
}
return d;
}
/**
* Casts to a double array.
*/
public static double[] toDouble(int[] array) {
double[] rv = new double[array.length];
for (int i = 0; i < array.length; i++) {
rv[i] = array[i];
}
return rv;
}
/** needed because Arrays.asList() won't to autoboxing,
* so if you give it a primitive array you get a
* singleton list back with just that array as an element.
*/
public static List asList(int[] array) {
List l = new ArrayList<>();
for (int i : array) {
l.add(i);
}
return l;
}
public static double[] asPrimitiveDoubleArray(Collection d) {
double[] newD = new double[d.size()];
int i = 0;
for (Double j : d) {
newD[i++] = j;
}
return newD;
}
public static int[] asPrimitiveIntArray(Collection d) {
int[] newI = new int[d.size()];
int i = 0;
for (Integer j : d) {
newI[i++] = j;
}
return newI;
}
public static long[] copy(long[] arr) {
if (arr == null) { return null; }
long[] newArr = new long[arr.length];
System.arraycopy(arr, 0, newArr, 0, arr.length);
return newArr;
}
public static int[] copy(int[] i) {
if (i == null) { return null; }
int[] newI = new int[i.length];
System.arraycopy(i, 0, newI, 0, i.length);
return newI;
}
public static int[][] copy(int[][] i) {
if (i == null) { return null; }
int[][] newI = new int[i.length][];
for (int j = 0; j < newI.length; j++) {
newI[j] = copy(i[j]);
}
return newI;
}
public static double[] copy(double[] d) {
if (d == null) { return null; }
double[] newD = new double[d.length];
System.arraycopy(d, 0, newD, 0, d.length);
return newD;
}
public static double[][] copy(double[][] d) {
if (d == null) { return null; }
double[][] newD = new double[d.length][];
for (int i = 0; i < newD.length; i++) {
newD[i] = copy(d[i]);
}
return newD;
}
public static double[][][] copy(double[][][] d) {
if (d == null) { return null; }
double[][][] newD = new double[d.length][][];
for (int i = 0; i < newD.length; i++) {
newD[i] = copy(d[i]);
}
return newD;
}
public static float[] copy(float[] d) {
if (d == null) { return null; }
float[] newD = new float[d.length];
System.arraycopy(d, 0, newD, 0, d.length);
return newD;
}
public static float[][] copy(float[][] d) {
if (d == null) { return null; }
float[][] newD = new float[d.length][];
for (int i = 0; i < newD.length; i++) {
newD[i] = copy(d[i]);
}
return newD;
}
public static float[][][] copy(float[][][] d) {
if (d == null) { return null; }
float[][][] newD = new float[d.length][][];
for (int i = 0; i < newD.length; i++) {
newD[i] = copy(d[i]);
}
return newD;
}
public static String toString(double[][] b) {
StringBuilder result = new StringBuilder("[");
for (int i = 0; i < b.length; i++) {
result.append(Arrays.toString(b[i]));
if(i < b.length-1)
result.append(',');
}
result.append(']');
return result.toString();
}
public static String toString(boolean[][] b) {
StringBuilder result = new StringBuilder("[");
for (int i = 0; i < b.length; i++) {
result.append(Arrays.toString(b[i]));
if(i < b.length-1)
result.append(',');
}
result.append(']');
return result.toString();
}
public static long[] toPrimitive(Long[] in) {
return toPrimitive(in,0L);
}
public static int[] toPrimitive(Integer[] in) {
return toPrimitive(in,0);
}
public static short[] toPrimitive(Short[] in) {
return toPrimitive(in,(short)0);
}
public static char[] toPrimitive(Character[] in) {
return toPrimitive(in,(char)0);
}
public static double[] toPrimitive(Double[] in) {
return toPrimitive(in,0.0);
}
public static long[] toPrimitive(Long[] in, long valueForNull) {
if (in == null)
return null;
final long[] out = new long[in.length];
for (int i = 0; i < in.length; i++) {
Long b = in[i];
out[i] = (b == null ? valueForNull : b);
}
return out;
}
public static int[] toPrimitive(Integer[] in, int valueForNull) {
if (in == null)
return null;
final int[] out = new int[in.length];
for (int i = 0; i < in.length; i++) {
Integer b = in[i];
out[i] = (b == null ? valueForNull : b);
}
return out;
}
public static short[] toPrimitive(Short[] in, short valueForNull) {
if (in == null)
return null;
final short[] out = new short[in.length];
for (int i = 0; i < in.length; i++) {
Short b = in[i];
out[i] = (b == null ? valueForNull : b);
}
return out;
}
public static char[] toPrimitive(Character[] in, char valueForNull) {
if (in == null)
return null;
final char[] out = new char[in.length];
for (int i = 0; i < in.length; i++) {
Character b = in[i];
out[i] = (b == null ? valueForNull : b);
}
return out;
}
public static double[] toDoubleArray(String[] in) {
double[] ret = new double[in.length];
for (int i = 0; i < in.length; i++)
ret[i] = Double.parseDouble(in[i]);
return ret;
}
public static double[] toPrimitive(Double[] in, double valueForNull) {
if (in == null)
return null;
final double[] out = new double[in.length];
for (int i = 0; i < in.length; i++) {
Double b = in[i];
out[i] = (b == null ? valueForNull : b);
}
return out;
}
/**
* Provides a consistent ordering over arrays. First compares by the
* first element. If that element is equal, the next element is
* considered, and so on. This is the array version of
* {@link edu.stanford.nlp.util.CollectionUtils#compareLists}
* and uses the same logic when the arrays are of different lengths.
*/
public static > int compareArrays(T[] first, T[] second) {
List firstAsList = Arrays.asList(first);
List secondAsList = Arrays.asList(second);
return CollectionUtils.compareLists(firstAsList, secondAsList);
}
/* -- This is an older more direct implementation of the above, but not necessary unless for performance
public static > int compareArrays(C[] a1, C[] a2) {
int len = Math.min(a1.length, a2.length);
for (int i = 0; i < len; i++) {
int comparison = a1[i].compareTo(a2[i]);
if (comparison != 0) return comparison;
}
// one is a prefix of the other, or they're identical
if (a1.length < a2.length) return -1;
if (a1.length > a2.length) return 1;
return 0;
}
*/
public static List getSubListIndex(Object[] tofind, Object[] tokens){
return getSubListIndex(tofind, tokens, (o1) -> o1.first().equals(o1.second()));
}
/**
* If tofind is a part of tokens, it finds the ****starting index***** of tofind in tokens
* If tofind is not a sub-array of tokens, then it returns null
* note that tokens sublist should have the exact elements and order as in tofind
* @param tofind array you want to find in tokens
* @param tokens
* @param matchingFunction function that takes (tofindtoken, token) pair and returns whether they match
* @return starting index of the sublist
*/
public static List getSubListIndex(Object[] tofind, Object[] tokens, Function matchingFunction){
if(tofind.length > tokens.length)
return null;
List allIndices = new ArrayList<>();
boolean matched = false;
int index = -1;
int lastUnmatchedIndex = 0;
for(int i = 0 ; i < tokens.length;){
for(int j = 0; j < tofind.length ;){
if(matchingFunction.apply(new Pair(tofind[j], tokens[i]))){
index = i;
i++;
j++;
if(j == tofind.length)
{
matched = true;
break;
}
}else{
j = 0;
i = lastUnmatchedIndex +1;
lastUnmatchedIndex = i;
index = -1;
if(lastUnmatchedIndex == tokens.length)
break;
}
if(i >= tokens.length){
index = -1;
break;
}
}
if(i == tokens.length || matched){
if(index >= 0)
//index = index - l1.length + 1;
allIndices.add(index - tofind.length + 1);
matched = false;
lastUnmatchedIndex = index;
//break;
}
}
//get starting point
return allIndices;
}
/** Returns a new array which has the numbers in the input array
* L1-normalized.
*
* @param ar Input array
* @return New array that has L1 normalized form of input array
*/
public static double[] normalize(double[] ar) {
double[] ar2 = new double[ar.length];
double total = 0.0;
for (double d : ar) {
total += d;
}
for (int i = 0; i < ar.length; i++) {
ar2[i] = ar[i]/total;
}
return ar2;
}
public static Object[] subArray(Object[] arr, int startindexInclusive, int endindexExclusive){
if(arr == null)
return arr;
Class type = arr.getClass().getComponentType();
if(endindexExclusive < startindexInclusive || startindexInclusive > arr.length -1 )
return (Object[]) Array.newInstance(type, 0);
if(endindexExclusive > arr.length)
endindexExclusive = arr.length;
if(startindexInclusive < 0)
startindexInclusive = 0;
Object[] b = (Object[]) Array.newInstance(type, endindexExclusive - startindexInclusive);
System.arraycopy(arr, startindexInclusive, b, 0, endindexExclusive - startindexInclusive);
return b;
}
public static int compareBooleanArrays(boolean[] a1, boolean[] a2) {
int len = Math.min(a1.length, a2.length);
for (int i = 0; i < len; i++) {
if (!a1[i] && a2[i]) return -1;
if (a1[i] && !a2[i]) return 1;
}
// one is a prefix of the other, or they're identical
if (a1.length < a2.length) return -1;
if (a1.length > a2.length) return 1;
return 0;
}
public static String toString(double[] doubles, String glue) {
String s = "";
for(int i = 0; i < doubles.length; i++){
if(i==0)
s = String.valueOf(doubles[i]);
else
s+= glue + String.valueOf(doubles[i]);
}
return s;
}
}