//+------------------------------------------------------------------+
//| StringArraySort.mq4 |
//| Copyright © 2005, MetaQuotes Software Corp. |
//| http://www.metaquotes.net |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2005, MetaQuotes Software Corp."
#property link "http://www.metaquotes.net"
#property stacksize 512000
//+------------------------------------------------------------------+
//| StringArray Sorting sample |
//+------------------------------------------------------------------+
int start()
{
string text[100]; // array to sort
string line; // string for reading
int text_size=100; // initial array size
int lines_read=0; // realy read lines count
int file; // file
int start,total; // claculating times
int min,sec,hsec,tmp; // for human time print
int i;
//---- opening text file
file=FileOpen("list.txt",FILE_CSV|FILE_READ,0x7F);
if(file<0)
{
Print("can\'t open list.txt for reading");
return(0);
}
//---- reading file to text array
while(FileIsEnding(file)==false)
{
line=FileReadString(file);
//---- when array size is less than need-grow it
if(lines_read>=text_size)
{
ArrayResize(text,text_size+100);
text_size+=100;
}
//---- empty strings dropped
if(StringLen(line)<1) continue;
text[lines_read]=line;
lines_read++;
}
//----
FileClose(file);
//---- now sort array
start=GetTickCount();
SortStrArrayRange(text,0,lines_read);
//SortStrArray(text);
total=GetTickCount()-start;
//---- converting timespan to human presentation
min=total/60000;
tmp=total%60000;
sec=tmp/1000;
hsec=tmp%1000;
//---- outpit results
Print("Array sort time is ",min," min ",sec," sec ",hsec, " msec");
//---- write text array to file
file=FileOpen("sorted_list.txt",FILE_CSV|FILE_WRITE);
if(file<0)
{
Print("can\'t open sorted_list.txt for writing");
return(0);
}
//----
for(i=0;i<lines_read;i++)
FileWrite(file,text[i]);
//----
FileClose(file);
//----
return(0);
}
//+------------------------------------------------------------------+
//| sorting range wraper |
//+------------------------------------------------------------------+
void SortStrArrayRange(string& A[],int start,int count)
{
QSortStringArray(A,start,(start+count)-1);
}
//+------------------------------------------------------------------+
//| main sorting function |
//+------------------------------------------------------------------+
void QSortStringArray(string& A[],int low,int high)
{
string pivot, tmp;
int scan_forward, scan_back;
int middle;
//---- if elements to sort less than 2 - return.
if(high-low<=0) return(0);
else
if(high-low==1)
{
//---- if count of elements to sort equal to 2 swap it if need
if(A[high]<A[low])
{
tmp=A[low];
A[low]=A[high];
A[high]=tmp;
}
return(0);
}
//---- calc middle element and store it in the pivot variable.
middle=(low+high)/2;
pivot=A[middle];
//---- swap middle and first elements
tmp=A[middle];
A[middle]=A[low];
A[low]=tmp;
//---- initializing scan_up and scan_down indexes
scan_forward=low+1;
scan_back=high;
//---- scan elements that places in opposite lists.
while(scan_forward<scan_back)
{
//---- scan to forward. stop when crossing second list or current element greater than middle.
while(scan_forward <= scan_back && A[scan_forward]<=pivot) scan_forward++;
//---- scan to backward. stop when current element greater than or equal to middle.
while(A[scan_back]>pivot) scan_back--;
//---- if scan indexes not crossed they points to elements need to swap.
if(scan_forward < scan_back)
{
tmp=A[scan_forward];
A[scan_forward]=A[scan_back];
A[scan_back]=tmp;
}
}
//---- swap first and dividing elements
A[low] = A[scan_back];
//---- swap middle and dividing elements
A[scan_back] = pivot;
//---- if first sublist has 2 or more elements sort it's too
if(low < scan_back-1) QSortStringArray(A, low, scan_back-1);
//---- if second sublist has 2 or more elements sort it's too
if(scan_back+1 < high) QSortStringArray(A, scan_back+1, high);
//---- that's all
return(0);
}
//+------------------------------------------------------------------+
Sample
Analysis
Market Information Used:
Indicator Curves created:
Indicators Used:
Custom Indicators Used:
Order Management characteristics:
Other Features:
Uses files from the file system
It reads information from a file
It writes information to file