How to read data from file and immediately write it back - MQL4 and MetaTrader 4

Tamul 2017.03.27 08:46 #1681

Good afternoon. I can't read data from file and immediately write it back. If I uncomment a code fragment with loops and MathRand(), the file gets mush as it should be. But if lines are left commented out (already there is mess in the file), then the next time I enable/disable the Expert Advisor, the file will contain zeros. The read-write arrays are double ROM1[128][128] and double ROM2[3][128]. The arrays are not changed anywhere else in the code, only read. Here is a piece of code:

int init()
   {
   Print ("Сработала ф-ия init"); // Сообщение
   Handle=FileOpen("Neuro",FILE_BIN|FILE_READ|FILE_WRITE);// Открытие файла на чтение и запись
   FileSeek(Handle, 0, SEEK_SET); //указатель на начало файла
   FileReadArray(Handle, ROM1);
   FileSeek(Handle, 131073, SEEK_SET); //указатель на конец первого массива
   FileReadArray(Handle, ROM2);

/*
   for(i=0; i<128; i++) //заполнение памяти первого слоя кашей
      {
      for(k=0; k<128; k++)
         {
         ROM1[i][k] = (MathRand()-16383)/3200;
         }
      }
   for(i=0; i<3; i++) //заполнение памяти второго слоя кашей
      {
      for(k=0; k<128; k++)
         {
         ROM1[i][k] = (MathRand()-16383)/3200;
         }
      }
*/
   return(0);
   }
//--------------------------------------------------------------------
int deinit()
   {
   FileSeek(Handle, 0, SEEK_SET);
   FileWriteArray(Handle, ROM1);
   FileSeek(Handle, 131073, SEEK_SET);
   FileWriteArray(Handle, ROM2);
   FileClose(Handle);
   return(0);
   }

Please help me to understand this. Thank you.

[Archive!] Any rookie question, File Read/Write problems Any rookie question, so

var58 2017.03.28 18:32 #1682

Hello, could you please tell me how to write in the EA code

condition to search for a signal

For example:

There is an order in the market with magic 565 open at 13:00

In the EA there is a condition that in order to open the order

in the market an order with a 565 magic number, how can I in my Expert Advisor postpone the search for the signal by one

The search for a signal to start at 14:00.

I currently see a situation where at 13:00, an order with Magic 565 is opened

and the owl opens its order at 13:00:02.

two identical orders.

Thank you.

[ARCHIVE] Any rookie question, [ARCHIVE!] Any rookie question, Questions from Beginners MQL4

Artyom Trishkin 2017.03.28 18:40 #1683

var58:

Hello, could you please tell me how to write in the EA code

condition to search for a signal

For example:

There is an order in the market with magic 565 open at 13:00

In the EA there is a condition that in order to open the order

in the market an order with a 565 magic number, how can I in my Expert Advisor postpone the search for the signal by one

The search for a signal to start at 14:00.

I currently see a situation where at 13:00, an order with Magic 565 is opened

and the owl opens its order at 13:00:02.

two identical orders.

Thank you.

You can search for a signal whenever you like but the opening of a position should be timed.

Watch the time of opening a position with magic 565 and watch the current time. If the current time is longer than the time of opening a position with magic 565 by the specified number of minutes, then you can open a position.

EA not to open How to start with [WARNING CLOSED!] Any newbie

var58 2017.03.28 19:28 #1684

Artyom Trishkin:

You can search for a signal whenever you want, but you must allow a position to be opened by time.

See the time of opening a position with magic 565 and see the current time. If the current time is longer than the opening time of Magik 565 by a given number of minutes, then the position may be opened.

Thank you very much. What does it look like in the code?

Tamul 2017.03.28 19:30 #1685

Good afternoon. I can't read data from file and immediately write it back. If I uncomment a code fragment with loops and MathRand(), the file gets mush as it should be. But if lines are left commented out (already there is mess in the file), then the next time I enable/disable the Expert Advisor, the file will contain zeros. The read-write arrays are double ROM1[128][128] and double ROM2[3][128]. The arrays are not changed anywhere else in the code, only read. Here is a bit of code:

A little bit of it. The function won't read a two-dimensional array double, though it will write it correctly.

I have made a loop for element-by-element reading. May be, it may be of use to somebody.

{
FileSeek(Handle, n, SEEK_SET); //изменение позиции файлового курсора
Neuron[k][i].rom[l] = FileReadDouble(Handle, DOUBLE_VALUE); //загрузка из файла
n=n+8;
}

Testing real-time forecasting systems Any rookie question, so Array copy error

Artyom Trishkin 2017.03.28 20:08 #1686

var58:

Thank you very much. What does it look like in code?

And this is not free code writing, but help for those who are trying to write them themselves, but can't get it right.

Show us what you can't do in your code - we'll help you.

[ARCHIVE] Any rookie question, Indicator Modification 2 Any rookie question, so

Alexey Viktorov 2017.03.28 20:55 #1687

Tamul:

I've worked it out a bit. The two-dimensional array double function does not want to read, although it writes fine.

I have made a loop-by-loop reading. Maybe someone will need it.

{
FileSeek(Handle, n, SEEK_SET); //изменение позиции файлового курсора
Neuron[k][i].rom[l] = FileReadDouble(Handle, DOUBLE_VALUE); //загрузка из файла
n=n+8;
}

Why should I offer such crutches to people, just because I haven't coped with the task myself?

To read a two-dimensional array from a file, it should be a two-dimensional array prepared for it.

If I remember that code sample correctly, I did not see that the file is closed after being written. An empty file is created and data are written into it but this filled file is stored in the main memory and the file data can only be read from the disk. As a result, the file looks like it has been written but physically it is not on the disk... In order to save the data to disk, one should either close the file or forcibly save it to disk.

Single array calculation during [Archive!] Any rookie question, Writing reading and saving

var58 2017.03.29 07:42 #1688

Artyom Trishkin:

And this is not free code writing, but help for those who are trying to write them themselves, but can't get it right.

Show us what you can't do in your code and we'll help.

thanks

maxon777 2017.03.29 15:17 #1689

Hello! Please write a simple (very simple) example in mql4. I am just a complete beginner.

1) open a pending order when it reaches a certain value (i.e. if the price is 0.7777, then open a pending order)

2) Close a market order when it has reached any value (i.e. if the price is 0.6666, then close the order).

I can't even close an order using a unique order number. I want to try to change the current state of my trading robot, but I don't understand anything.

I tried to read a tutorial from this site, but no effect (maybe I'm so stupid), and the elementary examples are somehow not on the Internet. Thanks in advance

[Archive!] Writing an advisor I'm new at this Delete pending order after

Sergey Gritsay 2017.03.29 15:34 #1690

maxon777:

Hello! Please write a simple (very simple) example in mql4. I am just a complete beginner.

1) open a pending order when it reaches any value (i.e. if the price is 0.7777, then open a pending order)

2) Close a market order when it has reached any value (i.e. if the price is 0.6666, then close the order).

I can't even close an order using a unique order number. I want to try to change the current state of my trading robot, but I don't understand anything.

I tried to read a tutorial from this site, but no effect (maybe I'm so stupid), and the elementary examples are somehow not on the Internet. Thanks in advance

If you have problems with pending orders, look for them on the CodeBase and see how the code is written.

Any questions from newcomers on MQL4 and MQL5, help and discussion on algorithms and codes - page 169