The function expected an Array here, but found a STRING

AFL Programming
#1

Hello Everyone,
For sending order to my broker, it requires a unique Token number for each ticker. I can assign token number at start of afl for the tickers as shown in below afl.

ACC29JUL21FUT = 53184; //Assigned Token Number to ACC29JUL21FUT
BEL29JUL21FUT = 53205; //Assigned Token Number to BEL29JUL21FUT (Just added to show as Token number will be assigned to more than 100 tickers here.)

_SECTION_BEGIN("Angel_Token");

Sym_AB= Name(); //Ticker in Amibroker database (In this example Name() = ACC-I)
Sym = StrTrim( Sym_AB, "-I", 2); //Ticker in Broker terminal
Sym_Fut = Sym+"29JUL21FUT"; //Future Ticker

Filter = 1;

AddtextColumn(Sym_AB,"Ticker in AB   ");//Ticker in Amibroker database
AddtextColumn(Sym,"Symbol    "); //Ticker in Broker terminal
AddtextColumn(Sym_Fut,"Future Symbol         ");//Future Ticker

AddColumn(Sym_Fut,"Token Assigned",1); //This should also return value 53184(Assigned in first line of code) because Sym_Fut = ACC29JUL21FUT, but it is showing error "The function expected an Array here, but found a STRING." 

_SECTION_END();

In the last line of above code I want to get the value 53184. Have I missed anything in above code?
What function can I use to return the value of token number which is 53184.?
Thank you.

#2 
AddtextColumn(Sym_Fut,"Future Symbol         ");

As the error states, you are using a function that needs an array and not a string. Use the AddTextColumn to get a string.

1 Like
#3

AddColumn is for numeric output not for Strings.
For String you have to use AddTextColumn.

Filter = status("lastbarinrange");
AddColumn(C, "THIS IS ARRAY", 1.2);
AddColumn(1000, "THIS IS NUMBER", 1.2);
AddTextColumn("Hello World", "This is STRING");

If you want to output value then e.g.

ACC29JUL21FUT = 53184; //Assigned Token Number to ACC29JUL21FUT
BEL29JUL21FUT = 53205; //Assigned Token Number to BEL29JUL21FUT (Just added to show as Token number will be assigned to more than 100 tickers here.)

if ( Name() == "ACC-I" )
	token = ACC29JUL21FUT;
//else if ( Name() == "...." )
//	token = ...;
else	
	token = Null;

// Or use switch statement instead of if-else
	
AddColumn(token,"Token Assigned",1);
1 Like
#4

Thank you everyone.
I found the solution. With the following code, I got the desired result:

StaticVarSetText("ACC29JUL21FUT","53184"); //Assigned Token Number to ACC29JUL21FUT
StaticVarSetText("BEL29JUL21FUT","53205"); //Assigned Token Number to BEL29JUL21FUT (Just added to show as Token number will be assigned to more than 100 tickers here.)

_SECTION_BEGIN("Angel_Token");

Sym_AB= Name(); //Ticker in Amibroker database (In this example Name() = ACC-I)
Sym = StrTrim( Sym_AB, "-I", 2); //Ticker in Broker terminal
Sym_Fut = Sym+"29JUL21FUT"; //Future Ticker of Symbol

Filter = 1;

AddtextColumn(Sym_AB,"Ticker in AB   ");//Ticker in Amibroker database
AddtextColumn(Sym,"Symbol    "); //Ticker in Broker terminal
AddtextColumn(Sym_Fut,"Future Symbol         ");//Future Ticker of Symbol

AddtextColumn(StaticVarGetText(Sym_Fut),"Token Assigned",1); //With this I am getting the 53184.

_SECTION_END();
#5

That is not a solution but total non sense.
You do not need Static vars in same code.
What a waste.

Everything is dependent on ticker symbol so you can just use Name() function and save lots of code lines and functions.

And again you do not need static vars.

VarSetText("ACC-I","53184"); //Assigned Token Number to ACC29JUL21FUT
VarSetText("BEL-I","53205"); //Assigned Token Number to BEL29JUL21FUT (Just added to show as Token number will be assigned to more than 100 tickers here.)

_SECTION_BEGIN("Angel_Token");

Sym_AB= Name(); //Ticker in Amibroker database (In this example Name() = ACC-I)

Filter = 1;

AddtextColumn(Sym_AB,"Ticker in AB   ");//Ticker in Amibroker database
AddtextColumn(VarGetText(Name()),"Token Assigned (...29JUL21FUT)",1); //With this I am getting the 53184.
1 Like
#6

Thank you very much. Your solution is working perfectly.
I am not an expert in coding. Can you please let me know, why we should not use StaticVarSetText. What are the disadvantages of using StaticVarSetText?

Thanks.

#7

Mainly because it uses up precious memory unnecessarily (when StaticVarSetText is not required).

#8

Static variables in AFL have TWO purposes.

Purpose 1: to keep STATE data between executions of the formula
Purpose 2: to SHARE data between formulas

All other uses are incorrect. Because of their per-process global characteristics, they are:

  • slower than regular variables
  • visible from other formulas (so you can have undesired side effect if more than one formula uses same static variable name)
  • require get/set function calls instead of plain assignments
  • consume RAM for as long as AmiBroker is open (also between formula executions)

So you SHOULD NOT use static variables, unless you have good reason to do so (see purpose 1 and/or 2)

1 Like
#9

Thank you very much .

#10

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