Algorith that determinates frequency of string combinations MQL4 - algorithm

I have csv file like this:
1392249600;EUR;CHF;USD;JPY;GBP
1392163200;GBP;JPY;USD;CHF;EUR
1392076800;GBP;CHF;EUR;JPY;USD
1391990400;JPY;USD;EUR;CHF;GBP
1391904000;GBP;EUR;CHF;USD;JPY
1391731200;GBP;EUR;CHF;JPY;USD
1391644800;EUR;CHF;USD;JPY;GBP
1391558400;JPY;USD;EUR;CHF;GBP
There can be over 15 000 rows in that file. I am trying to write code that could do such thing:
1.Takes first row saves it as parent. Then takes next 3 days as that childs.
2.Counts how often and which combination off childs with that parent are inside this file.
3.It creates something like summary for that so I could read todays combination and script shows the only the most frequent child combinations for next 3 days.
I don't have mathematical thinking so I have big problems to find solution myself.
What I think first I need script that generates all posible combinations of these colums made of EUR,CHF,USD,JPY,GBP so there is posible 5*4*3*2*1 = 120 combinations. Because they cant repeat in single row.
It will be like this.
First parent will be combination from first row like this: EUR;CHF;USD;JPY;GBP
Then 3 childs would be
GBP;JPY;USD;CHF;EUR
GBP;CHF;EUR;JPY;USD
JPY;USD;EUR;CHF;GBP
It saves this combination off parent and child elements.
Then again it starts from begining of the file, but moves one row below(like iteration +1).
then next all childs would be
GBP;CHF;EUR;JPY;USD
JPY;USD;EUR;CHF;GBP
GBP;EUR;CHF;USD;JPY
And again it saves these combinations for counting and make some frequency results.
And this cycle repeats for all rows on csv file.
Is there maybe some tips I should consider how to create this type of programm ?
Any tip would be great !
Thank You Very Much!
BB

Can you please clarify whether first value in a row in your file is date/time? 1392249600;EUR;CHF;USD;JPY;GBP
If yes, are you expecting that there will total 4 rows with the same date/time?
Or else you just need to go sequentially and use Line-1 as parent and then Line-2, Line-3, Line-4 as child and goes on... so that Line-5 becomes parent again?
To check whether country code is equivalent or not, you can use below kind of code. I am not 100% sure about your requirement, please correct me if you think this is not what you are looking for and I will try to answer you in other way:
package com.collections;
public class CountryCodeComparison {
public static void main(String[] args) {
//Read every row and sequentially insert value in CountryCode object.
//For ex. your row is: 1392163200;GBP;JPY;USD;CHF;EUR
String s1 = "1392163200;GBP;JPY;USD;CHF;EUR";
String [] array1 = s1.split(";");
CountryCode cc1 = new CountryCode(array1[1], array1[2], array1[1], array1[4], array1[5]);
//For ex. your row is: 1392076800;GBP;CHF;EUR;JPY;USD
String s2 = "1392076800;GBP;CHF;EUR;JPY;USD";
String [] array2 = s2.split(";");
CountryCode cc2 = new CountryCode(array2[1], array2[2], array2[1], array2[4], array2[5]);
if(cc1.equals(cc2)) {
System.out.println("Both CountryCode objects are equal.");
} else {
System.out.println("Both CountryCode objects are NOT equal.");
}
}
}
class CountryCode {
private String countryCode1;
private String countryCode2;
private String countryCode3;
private String countryCode4;
private String countryCode5;
public CountryCode(String countryCode1, String countryCode2,
String countryCode3, String countryCode4, String countryCode5) {
this.countryCode1 = countryCode1;
this.countryCode2 = countryCode2;
this.countryCode3 = countryCode3;
this.countryCode4 = countryCode4;
this.countryCode5 = countryCode5;
}
#Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result
+ ((countryCode1 == null) ? 0 : countryCode1.hashCode());
result = prime * result
+ ((countryCode2 == null) ? 0 : countryCode2.hashCode());
result = prime * result
+ ((countryCode3 == null) ? 0 : countryCode3.hashCode());
result = prime * result
+ ((countryCode4 == null) ? 0 : countryCode4.hashCode());
result = prime * result
+ ((countryCode5 == null) ? 0 : countryCode5.hashCode());
return result;
}
#Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
CountryCode other = (CountryCode) obj;
if (countryCode1 == null) {
if (other.countryCode1 != null)
return false;
} else if (!countryCode1.equals(other.countryCode1))
return false;
if (countryCode2 == null) {
if (other.countryCode2 != null)
return false;
} else if (!countryCode2.equals(other.countryCode2))
return false;
if (countryCode3 == null) {
if (other.countryCode3 != null)
return false;
} else if (!countryCode3.equals(other.countryCode3))
return false;
if (countryCode4 == null) {
if (other.countryCode4 != null)
return false;
} else if (!countryCode4.equals(other.countryCode4))
return false;
if (countryCode5 == null) {
if (other.countryCode5 != null)
return false;
} else if (!countryCode5.equals(other.countryCode5))
return false;
return true;
}
}

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QT - Wrong numbering in the case of two or more overlapping numberings

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When the second is over and I go to the first list, the numbers are counted from the beginning.
I tried to create a new list createList() but it didn't work
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how to write LINQ Query on three columns with a different value on each one

I'm new to this and this is my first question.
So far I have this, but it takes a long time to get the record:
public string BuscarPedimento(string patente, string pedimento2, string aduana)
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using (var context = new DataStage3Context())
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dynamic sort columns doesn't work in linq

in linq i'm tring to create gridview with dynamic sort columns
can any one help me what is worng on below code and why it does't work
// i created this function to get column value which i need to sorty by
private static string GetReflectedPropertyValue( object subject, string field)
{
object reflectedValue = subject.GetType().GetProperty(field).GetValue(subject, null);
return reflectedValue != null ? reflectedValue.ToString() : "";
}
// this is my grid query
List<ticketSearchRes> tickets = new List<ticketSearchRes>();
// here i deteermined sort direction ascending or desc
bool asc = (gridViewInputsVM.SortDirection == "asc") ? true : false;
bool desc = (gridViewInputsVM.SortDirection != "asc") ? true : false;
IQueryable<ticketSearchRes> source = (from ticket in _db.TblTicket
where (searchRes.assignTic == 1) ? ticket.AssignedTo == CurrentuserId : true
where (searchRes.myTicket == 1 && searchRes.forOthers != 1) ? ticket.CreatedFor == CurrentuserId : true
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// here i need to get dynamic column which i need to sort by
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How I would solve this is;
The partial class TicketSearchResList is part that fills in the partial method CustomSort. CustomSort accepts a property name and a sort direction and uses Reflection to sort on the named property. So far it should be easy to follow.
public partial class TicketSearchResList : List<TicketSearchRes>
{
partial void CustomSort(string propertyName, string direction);
public void Dump()
{
CustomSort("TicketTitle", "desc");
foreach(var ticket in this)
Console.WriteLine(ticket.ToString()); // For demo purposes
}
}
public partial class TicketSearchResList {
private string propertyName;
private string direction;
partial void CustomSort(string propertyName, string direction)
{
this.propertyName = propertyName;
this.direction = direction;
Sort(Comparer);
}
private int Comparer(TicketSearchRes x, TicketSearchRes y)
{
int directionChanger = direction == "asc" ? 1 : -1;
try
{
PropertyInfo lhs = x.GetType().GetProperty(propertyName);
PropertyInfo rhs = y.GetType().GetProperty(propertyName);
object o1 = lhs.GetValue(x, null);
object o2 = rhs.GetValue(y, null);
if(o1 is IComparable && o2 is IComparable)
{
return ((IComparable)o1).CompareTo(o2) * directionChanger;
}
// No sort
return 0;
}
catch(Exception ex)
{
Debug.WriteLine(ex.Message); // Should log something
return 0;
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The comparison is done using Reflection in the Comparer method. The direction is
used to determine whether to multiply the result by 1 or -1. CompareTo returns
an integer where -1 means less than, 0 means equal to, and 1 means greater than. Thus, if
you multiply the result by -1, you change the direction of the sort.
Finally, the TicketSearchResList class inherits from List<TicketResearchRes>. As you can see, the Dump method calls CustomSort, which, if implemented, yields ordered output.
Also, have a look at the Sort Method documented here by Microsoft

Optimizations for a recursive formula finding a path between two random nodes

I have written a recursive formula that finds a path between two nodes arranged in a grid pattern. My code works with two problems. The first is that sometimes the start node's position is changed from one to another number, but I fixed this by reassigning it after the recursion so it's not that big of a deal. The second issue is that it runs unbearably slow. It takes about 30 seconds to generate a 5x5 and I haven't been able to generate a 7x7 which is my ultimate goal. I am hoping that someone will see if there are any optimizations that can be made.
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The next part is the path. We want to find a random path (starting at 1) between the Start and End nodes that touches every other node without touching the same node twice. This is for a game, so it is important that it is random so the user doesn't play the same board twice. If this is not possible given the Start and End Positions, new Start and End positions are chosen and the algorithm is run again.
class Node
{
public int Key { get; set; }
public int? Position { get; set; } = null;
public Node Up { get; set; } = null;
public Node Down { get; set; } = null;
public Node Left { get; set; } = null;
public Node Right { get; set; } = null;
public bool Start = false;
public bool End = false;
public Node(int key)
{
Key = key;
}
}
public bool GeneratePath()
{
var current = nodeList.Where(w => w.Start).FirstOrDefault();
var start = current;
int position = 1;
bool Recurse(Node caller)
{
if (current.Position == null)
{
current.Position = position;
}
if (current.End)
{
return true;
}
var directions = GetDirections();
for (var i = 0; i < 4; i++)
{
var done = false;
if (directions[i] == 0 && current.Up != null && current.Up.Position == null
&& (!current.Up.End || position == n * n - 1))
{
var temp = current;
current = current.Up;
position++;
done = Recurse(temp);
}
else if (directions[i] == 1 && current.Down != null && current.Down.Position == null
&& (!current.Down.End || position == n * n - 1))
{
var temp = current;
current = current.Down;
position++;
done = Recurse(temp);
}
else if (directions[i] == 2 && current.Left != null && current.Left.Position == null
&& (!current.Left.End || position == n * n - 1))
{
var temp = current;
current = current.Left;
position++;
done = Recurse(temp);
}
else if (directions[i] == 3 && current.Right != null && current.Right.Position == null
&& (!current.Right.End || position == n*n - 1))
{
var temp = current;
current = current.Right;
position++;
done = Recurse(temp);
}
if(done)
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return true;
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}
current.Position = null;
position--;
if(caller == null)
{
return false;
}
current = caller;
return false;
}
var success = Recurse(null);
if (success)
{
start.Position = 1;
}
return success;
}
private int[] GetDirections()
{
List<int> toPerm = new List<int>();
for (var i = 0; i < 4; i++)
{
toPerm.Add(i);
}
Random random = new Random();
var perms = HelperMethods.GetPermutations(toPerm, toPerm.Count);
var randomNumber = random.Next(0, perms.Count());
var directions = perms.ElementAt(randomNumber).ToArray();
return directions;
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public static IEnumerable<IEnumerable<T>> GetPermutations<T>(IEnumerable<T> list, int length)
{
if (length == 1) return list.Select(t => new T[] { t });
return GetPermutations(list, length - 1)
.SelectMany(t => list.Where(o => !t.Contains(o)),
(t1, t2) => t1.Concat(new T[] { t2 }));
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To reiterate, I am wondering if there are optimizations I can make as it runs too slow for my purposes.
So I found an implementation of an amazing algorithm that can produce 10,000 7x7's in 12 seconds. You can find the implementation here. The author is Nathan Clisby and it is based off of a paper “Secondary structures in long compact polymers”. The idea is to produce a non-random path between the two points, then randomly mutate the path as many times as the user wishes. Supposedly, with enough iterations, this algorithm can produce paths that are nearly as random as the algorithm I posted in the question.
Way to go computer scientists!

How to get out of repetitive if statements?

While looking though some code of the project I'm working on, I've come across a pretty hefty method which does
the following:
public string DataField(int id, string fieldName)
{
var data = _dataRepository.Find(id);
if (data != null)
{
if (data.A == null)
{
data.A = fieldName;
_dataRepository.InsertOrUpdate(data);
return "A";
}
if (data.B == null)
{
data.B = fieldName;
_dataRepository.InsertOrUpdate(data);
return "B";
}
// keep going data.C through data.Z doing the exact same code
}
}
Obviously having 26 if statements just to determine if a property is null and then to update that property and do a database call is
probably very naive in implementation. What would be a better way of doing this unit of work?
Thankfully C# is able to inspect and assign class members dynamically, so one option would be to create a map list and iterate over that.
public string DataField(int id, string fieldName)
{
var data = _dataRepository.Find(id);
List<string> props = new List<string>();
props.Add("A");
props.Add("B");
props.Add("C");
if (data != null)
{
Type t = typeof(data).GetType();
foreach (String entry in props) {
PropertyInfo pi = t.GetProperty(entry);
if (pi.GetValue(data) == null) {
pi.SetValue(data, fieldName);
_dataRepository.InsertOrUpdate(data);
return entry;
}
}
}
}
You could just loop through all the character from 'A' to 'Z'. It gets difficult because you want to access an attribute of your 'data' object with the corresponding name, but that should (as far as I know) be possible through the C# reflection functionality.
While you get rid of the consecutive if-statements this still won't make your code nice :P
there is a fancy linq solution for your problem using reflection:
but as it was said before: your datastructure is not very well thought through
public String DataField(int id, string fieldName)
{
var data = new { Z = "test", B="asd"};
Type p = data.GetType();
var value = (from System.Reflection.PropertyInfo fi
in p.GetProperties().OrderBy((fi) => fi.Name)
where fi.Name.Length == 1 && fi.GetValue(data, null) != null
select fi.Name).FirstOrDefault();
return value;
}
ta taaaaaaaaa
like that you get the property but the update is not yet done.
var data = _dataRepository.Find(id);
If possible, you should use another DataType without those 26 properties. That new DataType should have 1 property and the Find method should return an instance of that new DataType; then, you could get rid of the 26 if in a more natural way.
To return "A", "B" ... "Z", you could use this:
return (char)65; //In this example this si an "A"
And work with some transformation from data.Value to a number between 65 and 90 (A to Z).
Since you always set the lowest alphabet field first and return, you can use an additional field in your class that tracks the first available field. For example, this can be an integer lowest_alphabet_unset and you'd update it whenever you set data.{X}:
Init:
lowest_alphabet_unset = 0;
In DataField:
lowest_alphabet_unset ++;
switch (lowest_alphabet_unset) {
case 1:
/* A is free */
/* do something */
return 'A';
[...]
case 7:
/* A through F taken */
data.G = fieldName;
_dataRepository.InsertOrUpdate(data);
return 'G';
[...]
}
N.B. -- do not use, if data is object rather that structure.
what comes to my mind is that, if A-Z are all same type, then you could theoretically access memory directly to check for non null values.
start = &data;
for (i = 0; i < 26; i++){
if ((typeof_elem) *(start + sizeof(elem)*i) != null){
*(start + sizeof(elem)*i) = fieldName;
return (char) (65 + i);
}
}
not tested but to give an idea ;)

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