Develop Reference

How to sort C# Datatable with empty column values at the end

I have a C# datatable with 1000's of rows. But primary 200 rows have empty values (multiple columns). Filter would happen to those columns as empty values to occupy as last. I want output will happen with in the table or new table with filter but not as linq rows. Please help me out
Pictures speaks more words, refer this for better understanding:

There are 2 things here that you should consider:
"Empty Value": To sort items that followed by empty value columns you need .OrderBy(s => String.IsNullOrEmpty(s["OrderNo"].ToString()))
"Order No Format": To sort custom order number you need to use IComparer<string>. As you show in your question I assume the format for Order No could be XXXXX or XXXX-XXXX.
So you need to first OrderBy empty values ThenBy your custom IComparer<string> something like this:
public class OrderNoComparer : IComparer<string>
{
public int Compare(string x, string y)
{
int xFirstValue = 0;
int xSecondValue = 0;
int yFirstValue = 0;
int ySecondValue = 0;
if (x.Contains("-"))
{
xFirstValue = Convert.ToInt32(x.Split(new char[] { '-' })[0]);
xSecondValue = Convert.ToInt32(x.Split(new char[] { '-' })[1]);
}
else
{
xFirstValue = Convert.ToInt32(x);
}
if (y.Contains("-"))
{
yFirstValue = Convert.ToInt32(y.Split(new char[] { '-' })[0]);
ySecondValue = Convert.ToInt32(y.Split(new char[] { '-' })[1]);
}
else
{
yFirstValue = Convert.ToInt32(y);
}
if (xFirstValue > yFirstValue)
{
return 1;
}
else if (xFirstValue < yFirstValue)
{
return -1;
}
else //means equal
{
if (xSecondValue > ySecondValue)
{
return 1;
}
else if (xSecondValue == ySecondValue)
{
return 0;
}
else
{
return -1;
}
}
}
}
Full example is here:
DataTable dtOrder = new DataTable();
dtOrder.Columns.Add("OrderNo");
var dr1 = dtOrder.NewRow();
dr1["OrderNo"] = "";
dtOrder.Rows.Add(dr1);
var dr2 = dtOrder.NewRow();
dr2["OrderNo"] = "569-875";
dtOrder.Rows.Add(dr2);
var dr3 = dtOrder.NewRow();
dr3["OrderNo"] = "569975";
dtOrder.Rows.Add(dr3);
var dr4 = dtOrder.NewRow();
dr4["OrderNo"] = "569865";
dtOrder.Rows.Add(dr4);
var dr5 = dtOrder.NewRow();
dr5["OrderNo"] = "569-975";
dtOrder.Rows.Add(dr5);
var dr6 = dtOrder.NewRow();
dr6["OrderNo"] = "569-875";
dtOrder.Rows.Add(dr6);
var result = dtOrder.AsEnumerable().AsQueryable()
.OrderBy(s => String.IsNullOrEmpty(s["OrderNo"].ToString()))
.ThenBy(o => o["OrderNo"].ToString(), new OrderNoComparer())
.ToList();
foreach (var item in result)
{
Console.WriteLine(item["OrderNo"]);
}
Then the output would be like you expected:
569-875
569-875
569-975
569865
569975

Find count of each consecutive characters

Need to find the count of each consecutive characters in a row.
Ex: aaaabbccaa
output: 4a2b2c2a
Character may repeat but need to count only consecutive ones. I also need to maintain original sequence.
I tried following but it groups all characters so was not useful.
str.GroupBy(c => c).Select(g => new { g.Key, Count = g.Count() }).ToList().ForEach(x => str+= x.Count + "" + x.Key)

Regular expression to the rescue ?
var myString = "aaaabbccaa";
var pattern = #"(\w)\1*";
var regExp = new Regex(pattern);
var matches = regExp.Matches(myString);
var tab = matches.Select(x => String.Format("{0}{1}", x.Value.First(), x.Value.Length));
var result = String.Join("", tab);

Here is a LINQ solution:
var input = "aaaabbccaa";
var result = string.IsNullOrEmpty(input) ? "" : string.Join("",input.Skip(1)
.Aggregate((t:input[0].ToString(),o:Enumerable.Empty<string>()),
(a,c)=>a.t[0]==c ? (a.t+c,a.o) : (c.ToString(),a.o.Append(a.t)),
a=>a.o.Append(a.t).Select(p => $"{p.Length}{p[0]}")));
Here is the iterator solution:
var result = RleString("aaaabbccaa");
private static IEnumerable<(char chr, int count)> Rle(string s)
{
if (string.IsNullOrEmpty(s)) yield break;
var lastchar = s.First(); // or s[0]
var count = 1;
foreach (char letter in s.Skip(1))
{
if (letter != lastchar)
{
yield return (lastchar, count);
lastchar = letter;
count = 0;
}
count++;
}
if (count > 0)
yield return (lastchar, count);
}
private static string RleString(string s)
{
return String.Join("",Rle(s).Select(z=>$"{z.count}{z.chr}"));
}

Non-LINQ solution (dotnetfiddle):
using System;
using System.Text;
public class Program
{
public static void Main()
{
// produces 4a2b2c2a
Console.WriteLine(GetConsecutiveGroups("aaaabbccaa"));
}
private static string GetConsecutiveGroups(string input)
{
var result = new StringBuilder();
var sb = new StringBuilder();
foreach (var c in input)
{
if (sb.Length == 0 || sb[sb.Length - 1] == c)
{
sb.Append(c);
}
else
{
result.Append($"{sb.Length}{sb[0]}");
sb.Clear();
sb.Append(c);
}
}
if (sb.Length > 0)
{
result.Append($"{sb.Length}{sb[0]}");
}
return result.ToString();
}
}

This small program will do the trick, but it's not a single line nice linq statement. Just my two cents.
using System;
using System.Linq;
using System.Collections.Generic;
public class Simple {
public static void Main() {
var text = "aaaabbccaa"; //output: 4a3b2c2a
var lista = new List<string>();
var previousLetter = text.Substring(1,1);
var item = string.Empty;
foreach (char letter in text)
{
if (previousLetter == letter.ToString()){
item += letter.ToString();
}
else
{
lista.Add(item);
item = letter.ToString();
}
previousLetter = letter.ToString();
}
lista.Add(item);
foreach (var i in lista)
Console.WriteLine(i.Substring(1,1) + i.Select(y => y).ToList().Count().ToString());
}
}

Here is my non-LINQ version that is quite fast compared to LINQ or Regex:
var prevChar = str[0];
var ct = 1;
var s = new StringBuilder();
var len = str.Length;
for (int j2 = 1; j2 < len; ++j2) {
if (str[j2] == prevChar)
++ct;
else {
s.Append(ct);
s.Append(prevChar);
ct = 1;
prevChar = str[j2];
}
}
s.Append(ct);
s.Append(prevChar);
var final = s.ToString();
}
My LINQ version looks like this, but uses a couple of extension methods I already had:
var ans = str.GroupByRuns().Select(s => $"{s.Count()}{s.Key}").Join();

var chars = "aaaabbccaa".ToCharArray();
int counter = 1;
for (var i = 0; i < chars.Count(); i++)
{
if (i + 1 >= chars.Count() || chars[i] != chars[i + 1])
{
Console.Write($"{counter}{chars[i]}");
counter = 1;
}
else
{
counter++;
}
}

You could have a character var and a counter var outside your Linq scope to keep track of the previous character and the current count and then use linq foreach, but I am just as curious as the rest to why you insist on doing this. Even if you do, the Solution may not be as easy to read as an iterative version and readability and maintenance overhead is very import if anyone else is ever going to read it.

Invalid rank specifier:expected ',' or ']' error

Before i asked my question, I read the previous posts.When I run the script, it shows Invalid rank specifier:expected ',' or ']' error at following code. BTW, I tried with new float[8939, 100]; but it still shows the error.
And also how can use hashtable to save the result where i wrote the hashtable comments.
namespace function
{
public partial class Form1 : Form
{
float userscore,itemscore,result;
string lineitem, lineuser;
float[][] a = new float[89395][100]; //<----the error is here
float[][] b = new float[1143600][100]; //<----the error is here
//float[,] c = new float[89395, 100];
StreamReader fileitem = new StreamReader("c:\\1.txt");
StreamReader fileuser = new StreamReader("c:\\2.txt");
public Form1()
{
InitializeComponent();
for (int x = 0; x <= 8939500; x++)
{
lineuser = fileuser.ReadLine();
string[] values = lineuser.Split(' ');
int userid, factoriduser;
foreach (string value in values)
{
userid = Convert.ToInt32(values[0]);
factoriduser = Convert.ToInt32(values[1]);
userscore = Convert.ToSingle(values[2]);
a[userid][factoriduser] = userscore;
}
}
for (int y = 0; y <= 114360000; y++)
{
lineitem = fileitem.ReadLine();
string[] valuesi = lineitem.Split(' ');
int itemid, factoriditem;
foreach (string value in valuesi)
{
itemid = Convert.ToInt32(valuesi[0]);
factoriditem = Convert.ToInt32(valuesi[1]);
itemscore = Convert.ToSingle(valuesi[2]);
b[itemid][factoriditem] = itemscore;
}
}
}
public float dotproduct(int userid,int itemid)
{
//get the score of 100 from user and item to dotproduct
float[] u_f = a[userid];
float[] i_f = b[itemid];
for (int i = 0; i <u_f.GetLength(1); i++)
{
result += u_f[userid] * i_f[itemid];
}
return result;
}
private void btn_recomm_Click(object sender, EventArgs e)
{
if(txtbx_id.Text==null)
{
MessageBox.Show("please insert user id");
}
if (txtbx_id.Text != null)
{
int sc = Convert.ToInt32(txtbx_id.Text);
if (sc>=0 &&sc<=89395)
{
for (int z=0;z<=1143600;z++)
{
dotproduct(sc,z);
}
//Hashtable hashtable = new Hashtable();
//put the result in hashtable
//foreach (DictionaryEntry entry in hashtable)
//{
//Console.WriteLine("{0}, {1}", entry.Key, entry.Value);
// }
}
}
if (txtbx_id==null &&txtbx_itemid==null)
{
int uid = Convert.ToInt32(txtbx_id.Text);
int iid = Convert.ToInt32(txtbx_itemid.Text);
{
if (uid>=0 && uid<=89395 && iid>=0 && iid<=1143600)
{
dotproduct(uid,iid);
MessageBox.Show("The Score of user id "+uid+" is "+result);
}
}
}
}

You cannot declare jagged array like that. You have to declare outer array first, and then declare all inner arrays:
float[][] a = new float[89395][];
for(int i = 0; i < 89395; i++)
a[i] = new float[100];
or you should change your array to multidimensional float[,] array:
float[,] a = new float[89395,100];

float[,] a = new float[89395,100];
float[,] b = new float[1143600,100];
Reference: http://msdn.microsoft.com/en-us/library/2yd9wwz4.aspx

You cannot make a new 2D array like that - you do it one dimension at a time. You can useva loop to initialize the second dimensiuon, or use LINQ:
float[][] a = Enumerable.Range(0, 89395).Select(i=>new float[100]).ToArray();

Set operation on a list of strings

I got a list of strings,on which I would like to do an operation which concats each item with rest of the items. The below test fails at the moment, I think the join is not the correct linq method I should be using- can you please let me know how to get this done? The pattern of the output should tell how the projection should be,if not the rule is simple:take one item and concatenate with all the other items and then move to the next item.Test below:
[Test]
public void Should_concatenate_all_items()
{
var items = new List<string> {"a", "b", "c", "d"};
var concatenatedList = items .Join(items , x => x, y => y, (x, y) => string.Concat(x, y));
foreach (var item in concatenatedList)
{
//Should output:ab
//Should output:ac
//Should output:ad
//Should output:bc
//Should output:bd
//Should output:cd
Console.WriteLine(item);
}
}
Note: I'm using .NET 3.5.

You could use something like this:
var concatenatedList =
from x in items.Select((str, idx) => new { str, idx })
from y in items.Skip(x.idx + 1)
select x.str + y;
Or in fluent syntax:
var concatenatedList =
items.Select((str, idx) => new { str, idx })
.SelectMany(x => items.Skip(x.idx + 1), (x, y) => x.str + y);

I think my solution may be overkill, but in real world situations it is probably more helpful. Also, I could not find a clean way to do it in Linq. Linq's Except does not seem suited for this.
You can use an IEnumerator to enumerate the values for you.
public class ConcatEnum : IEnumerator
{
public List<String> _values;
// Enumerators are positioned before the first element
// until the first MoveNext() call.
int position1 = 0;
int position2 = 0;
public ConcatEnum(List<String> list)
{
_values = list;
}
public bool MoveNext()
{
position2 = Math.Max(position2 + 1, position1 + 1);
if (position2 > _values.Count - 1){
position1++;
position2 = position1 + 1;
}
return position1 < _values.Count - 1;
}
public void Reset()
{
position1 = 0;
position2 = 0;
}
object IEnumerator.Current
{
get
{
return Current;
}
}
public String Current
{
get
{
try
{
return _values[position1] + _values[position2];
}
catch (IndexOutOfRangeException)
{
throw new InvalidOperationException();
}
}
}
public IEnumerator GetEnumerator()
{
this.Reset();
while (this.MoveNext())
{
yield return Current;
}
}
}
Call it like this:
var items = new List<string> { "a", "b", "c", "d" };
foreach (var i in new ConcatEnum(items))
{
//use values here
}

var concatenatedList = (from i in items
from x in items
where i != x
select string.Concat(i, x)).ToList();
For the exact output that you listed:
var concatenatedList = (from i in items
from x in items
where i != x && items.IndexOf(i) < items.IndexOf(x)
select string.Concat(i, x)).ToList();

What C# template engine that has clean separation between HTML and control code?

What C# template engine
that uses 'pure' HTML having only text and markers
sans any control flow like if, while, loop or expressions,
separating html from control code ?
Below is the example phone book list code,
expressing how this should be done:
string html=#"
<html><head><title>#title</title></head>
<body>
<table>
<tr>
<td> id</td> <td> name</td> <td> sex</td> <td>phones</td>
</tr><!--#contacts:-->
<tr>
<td>#id</td> <td>#name</td> <td>#sex</td>
<td>
<!--#phones:-->#phone <br/>
<!--:#phones-->
</td>
</tr><!--:#contacts-->
</table>
</body>
</html>";
var contacts = from c in db.contacts select c;
Marker m = new Marker(html);
Filler t = m.Mark("title");
t.Set("Phone book");
Filler c = m.Mark("contacts", "id,name,sex");
// **foreach** expressed in code, not in html
foreach(var contact in contacts) {
int id = contact.id;
c.Add(id, contact.name, contact.sex);
Filler p = c.Mark("phones", "phone");
var phones = from ph in db.phones
where ph.id == id
select new {ph.phone};
if (phones.Any()) {
foreach(var ph in phones) {
p.Add(ph);
}
} else {
fp.Clear();
}
}
Console.Out.WriteLine(m.Get());

Use this code:
Templet.cs
using System;
using System.Collections.Generic;
using System.Text;
using System.Text.RegularExpressions;
namespace templaten.com.Templaten
{
public class tRange
{
public int head, toe;
public tRange(int _head, int _toe)
{
head = _head;
toe = _toe;
}
}
public enum AType
{
VALUE = 0,
NAME = 1,
OPEN = 2,
CLOSE = 3,
GROUP = 4
}
public class Atom
{
private AType kin;
private string tag;
private object data;
private List<Atom> bag;
public Atom(string _tag = "",
AType _kin = AType.VALUE,
object _data = null)
{
tag = _tag;
if (String.IsNullOrEmpty(_tag))
_kin = AType.GROUP;
kin = _kin;
if (_kin == AType.GROUP)
bag = new List<Atom>();
else
bag = null;
data = _data;
}
public AType Kin
{
get { return kin; }
}
public string Tag
{
get { return tag; }
set { tag = value; }
}
public List<Atom> Bag
{
get { return bag; }
}
public object Data
{
get { return data; }
set { data = value; }
}
public int Add(string _tag = "",
AType _kin = AType.VALUE,
object _data = null)
{
if (bag != null)
{
bag.Add(new Atom(_tag, _kin, _data));
return bag.Count - 1;
}
else
{
return -1;
}
}
}
public class Templet
{
private string content;
string namepat = "\\w+";
string justName = "(\\w+)";
string namePre = "#";
string namePost = "";
string comment0 = "\\<!--\\s*";
string comment1 = "\\s*--\\>";
private Atom tokens; // parsed contents
private Dictionary<string, int> iNames; // name index
private Dictionary<string, tRange> iGroups; // groups index
private Atom buffer; // output buffer
private Dictionary<string, int> _iname; // output name index
private Dictionary<string, tRange> _igroup; // output index
public Templet(string Content = null)
{
Init(Content);
}
private int[] mark(string[] names, string group)
{
if (names == null || names.Length < 1) return null;
tRange t = new tRange(0, buffer.Bag.Count - 1);
if (group != null)
{
if (!_igroup.ContainsKey(group)) return null;
t = _igroup[group];
}
int[] marks = new int[names.Length];
for (int i = 0; i < marks.Length; i++)
marks[i] = -1;
for (int i = t.head; i <= t.toe; i++)
{
if (buffer.Bag[i].Kin == AType.NAME)
{
for (int j = 0; j < names.Length; j++)
{
if (String.Compare(
names[j],
buffer.Bag[i].Tag,
true) == 0)
{
marks[j] = i;
break;
}
}
}
}
return marks;
}
public Filler Mark(string group, string names)
{
Filler f = new Filler(this, names);
f.di = mark(f.names, group);
f.Group = group;
tRange t = null;
if (_igroup.ContainsKey(group)) t = _igroup[group];
f.Range = t;
return f;
}
public Filler Mark(string names)
{
Filler f = new Filler(this, names);
f.di = mark(f.names, null);
f.Group = "";
f.Range = null;
return f;
}
public void Set(int[] locations, object[] x)
{
int j = Math.Min(x.Length, locations.Length);
for (int i = 0; i < j; i++)
{
int l = locations[i];
if ((l >= 0) && (buffer.Bag[l] != null))
buffer.Bag[l].Data = x[i];
}
}
public void New(string group, int seq = 0)
{
// place new group copied from old group just below it
if (!( iGroups.ContainsKey(group)
&& _igroup.ContainsKey(group)
&& seq > 0)) return;
tRange newT = null;
tRange t = iGroups[group];
int beginRange = _igroup[group].toe + 1;
for (int i = t.head; i <= t.toe; i++)
{
buffer.Bag.Insert(beginRange,
new Atom(tokens.Bag[i].Tag,
tokens.Bag[i].Kin,
tokens.Bag[i].Data));
beginRange++;
}
newT = new tRange(t.toe + 1, t.toe + (t.toe - t.head + 1));
// rename past group
string pastGroup = group + "_" + seq;
t = _igroup[group];
buffer.Bag[t.head].Tag = pastGroup;
buffer.Bag[t.toe].Tag = pastGroup;
_igroup[pastGroup] = t;
// change group indexes
_igroup[group] = newT;
}
public void ReMark(Filler f, string group)
{
if (!_igroup.ContainsKey(group)) return;
Map(buffer, _iname, _igroup);
f.di = mark(f.names, group);
f.Range = _igroup[group];
}
private static void Indexing(string aname,
AType kin,
int i,
Dictionary<string, int> dd,
Dictionary<string, tRange> gg)
{
switch (kin)
{
case AType.NAME: // index all names
dd[aname] = i;
break;
case AType.OPEN: // index all groups
if (!gg.ContainsKey(aname))
gg[aname] = new tRange(i, -1);
else
gg[aname].head = i;
break;
case AType.CLOSE:
if (!gg.ContainsKey(aname))
gg[aname] = new tRange(-1, i);
else
gg[aname].toe = i;
break;
default:
break;
}
}
private static void Map(Atom oo,
Dictionary<string, int> dd,
Dictionary<string, tRange> gg)
{
for (int i = 0; i < oo.Bag.Count; i++)
{
string aname = oo.Bag[i].Tag;
Indexing(oo.Bag[i].Tag, oo.Bag[i].Kin, i, dd, gg);
}
}
public void Init(string Content = null)
{
content = Content;
tokens = new Atom("", AType.GROUP);
iNames = new Dictionary<string, int>();
iGroups = new Dictionary<string, tRange>();
// parse content into tokens
string namePattern = namePre + namepat + namePost;
string patterns =
"(?<var>" + namePattern + ")|" +
"(?<head>" + comment0 + namePattern + ":" + comment1 + ")|" +
"(?<toe>" + comment0 + ":" + namePattern + comment1 + ")";
Regex jn = new Regex(justName, RegexOptions.Compiled);
Regex r = new Regex(patterns, RegexOptions.Compiled);
MatchCollection ms = r.Matches(content);
int pre = 0;
foreach (Match m in ms)
{
tokens.Add(content.Substring(pre, m.Index - pre));
int idx = -1;
if (m.Groups.Count >= 3)
{
string aname = "";
MatchCollection x = jn.Matches(m.Value);
if (x.Count > 0 && x[0].Groups.Count > 1)
aname = x[0].Groups[1].ToString();
AType t = AType.VALUE;
if (m.Groups[1].Length > 0) t = AType.NAME;
if (m.Groups[2].Length > 0) t = AType.OPEN;
if (m.Groups[3].Length > 0) t = AType.CLOSE;
if (aname.Length > 0)
{
tokens.Add(aname, t);
idx = tokens.Bag.Count - 1;
}
Indexing(aname, t, idx, iNames, iGroups);
}
pre = m.Index + m.Length;
}
if (pre < content.Length)
tokens.Add(content.Substring(pre, content.Length - pre));
// copy tokens into buffer
buffer = new Atom("", AType.GROUP);
for (int i = 0; i < tokens.Bag.Count; i++)
buffer.Add(tokens.Bag[i].Tag, tokens.Bag[i].Kin);
// initialize index of output names
_iname = new Dictionary<string, int>();
foreach (string k in iNames.Keys)
_iname[k] = iNames[k];
// initialize index of output groups
_igroup = new Dictionary<string, tRange>();
foreach (string k in iGroups.Keys)
{
tRange t = iGroups[k];
_igroup[k] = new tRange(t.head, t.toe);
}
}
public string Get()
{
StringBuilder sb = new StringBuilder("");
for (int i = 0; i < buffer.Bag.Count; i++)
{
switch (buffer.Bag[i].Kin)
{
case AType.VALUE:
sb.Append(buffer.Bag[i].Tag);
break;
case AType.NAME:
sb.Append(buffer.Bag[i].Data);
break;
case AType.OPEN:
case AType.CLOSE:
break;
default: break;
}
}
return sb.ToString();
}
}
public class Filler
{
private Templet t = null;
public int[] di;
public string[] names;
public string Group { get; set; }
public tRange Range { get; set; }
private int seq = 0;
public Filler(Templet tl, string markers = null)
{
t = tl;
if (markers != null)
names = markers.Split(new char[] { ',' },
StringSplitOptions.RemoveEmptyEntries);
else
names = null;
}
public void init(int length)
{
di = new int[length];
for (int i = 0; i < length; i++)
di[i] = -1;
seq = 0;
Group = "";
Range = null;
}
// clear contents inside marked object or group
public void Clear()
{
object[] x = new object[di.Length];
for (int i = 0; i < di.Length; i++)
x[i] = null;
t.Set(di, x);
}
// set value for marked object,
// or add row to group and set value to columns
public void Set(params object[] x)
{
t.Set(di, x);
}
public void Add(params object[] x)
{
if (Group.Length > 0)
{
t.New(Group, seq);
++seq;
t.ReMark(this, Group);
}
t.Set(di, x);
}
}
}
Testing program
Program.cs
Templet m = new Templet(html);
Filler f= m.Mark("title");
f.Set("Phone book");
Filler fcontacts = m.Mark("contacts", "id,name,sex,phone");
fcontacts.Add(1, "Akhmad", "M", "123456");
fcontacts.Add(2, "Barry", "M", "234567");
fcontacts.Add(1, "Charles", "M", "345678");
Console.Out.WriteLine(m.Get());
Still can't do nested loop- yet.

Just use ASP.NET. Whether you use webforms or MVC, it's super easy to have C# in your .cs files, and HTML in your .aspx files.
As with anything in programming, it's 99% up to you to do things right. Flexible UI engines aren't going to enforce that you follow good coding practices.

In principle most any template engine you choose can separate HTML from control logic with the proper architecture. using an MVC (Or MVVM) pattern, if you construct your model in such a way that the controller contains the if/then logic instead of the view you can eliminate it from the view.
That said, the syntax you use is very close to Razor syntax which is easily available for ASP.NET MVC through NuGet packages.

I totally hear you. I built SharpFusion, which has some other stuff in it but if you look for the template.cs file you will see the handler that parses a HTML file and simply replaces out tokens with values that you've made in c#.
Because no XML parsing is done like ASP.NET the framework loads much faster than even an MVC site.
Another alternative is ServiceStack.