Problem with integer array- likely basic

[rnfpc]

I am trying following code to square a dynamic array of integers:

Code: Pascal  [Select][+][-]

1. program mysquare_prog;
2. {$mode objfpc}
3.  
4. type
5.         tarr = array of integer;
6. var
7.         arr : tarr;
8.  
9. function mysquare(sarr: tarr): tarr;
10. var
11.         outarr: tarr;
12.         i: integer;
13. begin
14.         outarr := tarr.create;
15.         outarr.setlength(length(sarr));
16.         for i in [0..length(sarr)-1] do
17.                 outarr[i] = sarr[i] * sarr[i];
18.         result := outarr;
19. end;
20.  
21. begin
22.         arr := tarr.create();
23.         setlength(arr, 10);
24.         arr.add(1);
25.         arr.add(2);
26.         arr.add(3);
27.         writeln(mysquare(arr));
28. end.
29.  

However, I am getting following error:

$ fpc rnmaparr.pas
Free Pascal Compiler version 3.0.0+dfsg-11+deb9u1 [2017/06/10] for i386
Copyright (c) 1993-2015 by Florian Klaempfl and others
Target OS: Linux for i386
Compiling rnmaparr.pas
rnmaparr.pas(16,9) Fatal: Syntax error, "CREATE" expected but "SETLENGTH" found
Fatal: Compilation aborted
Error: /usr/bin/ppc386 returned an error exitcode

I have already used create in previous statement but it is still looking for create. I suspect the problem is very basic since I have just started using Pascal. Thanks for your help.

[Handoko]

Not very sure, but maybe this is what you want:

Code: Pascal  [Select][+][-]

1. program mysquare_prog;
2.  
3. {$mode objfpc}
4.  
5. type
6.         tarr = array of integer;
7.  
8. var
9.         arr : tarr;
10.  
11. function mysquare(sarr: tarr): tarr;
12. var
13.         outarr: tarr;
14.         i: integer;
15. begin
16.         setlength(outarr, length(sarr));
17.         for i in [0..length(sarr)-1] do
18.                 outarr[i] := sarr[i] * sarr[i];
19.         result := outarr;
20. end;
21.  
22. var
23.         NewArr: tarr;
24.         i: Integer;
25. begin
26.         setlength(arr, 3);
27.         arr[0] := 1;
28.         arr[1] := 2;
29.         arr[2] := 3;
30.         NewArr := mysquare(arr);
31.         for i := 0 to Length(NewArr-1) do
32.                 writeln(NewArr[i]);
33. end.

~~~ correction ~~~
The line #31 above, it should be:
  for i := 0 to Length(NewArr)-1 do

Documentation about dynamic array:
https://wiki.freepascal.org/Dynamic_array

----------

You seems to have some programming knowledge but new in Pascal language. I recommend you to read the tutorials in the links in this post:

https://forum.lazarus.freepascal.org/index.php/topic,45078.msg317864.html#msg317864

[rnfpc]

Your code is giving error at this line:

Code: Pascal  [Select][+][-]

1. for i := 0 to Length(NewArr-1) do ....

The error is:

Error: Operator is not overloaded: "tarr" - "ShortInt"

It works with:

Code: Pascal  [Select][+][-]

1. for i := 0 to (Length(NewArr)-1) do ....

Thanks.

[totya]

I am trying following code to square a dynamic array of integers:

Quite terrible code See this workable sample:

Code: Pascal  [Select][+][-]

1. program Project1;
2.  
3. uses
4.   SysUtils;
5.  
6. type
7.   Tarr = array of integer;
8.  
9.   function mysquare(const sarr: Tarr): Tarr;
10.   var
11.     i: integer;
12.   begin
13.     Setlength(Result, length(sarr));
14.  
15.     for i := low(sarr) to high(sarr) do
16.       Result[i] := sarr[i] * sarr[i];
17.   end;
18.  
19. const
20.   arr_count = 11;
21. var
22.   arr_in, arr_out: Tarr;
23.   i: integer;
24. begin
25.   setlength(arr_in, arr_count);
26.   setlength(arr_out, arr_count);
27.  
28.   for i := low(arr_in) to high(arr_in) do
29.     arr_in[i] := i;
30.  
31.   arr_out := mysquare(arr_in);
32.  
33.   for i := low(arr_out) to high(arr_out) do
34.     WriteLn(Format('%d. %d -> %d', [i, arr_in[i], arr_out[i]]));
35.  
36.   ReadLN;
37. end.

[totya]

Your code is giving error at this line:

Code: Pascal  [Select][+][-]

1. for i := 0 to Length(NewArr-1) do ....

Code: Pascal  [Select][+][-]

1. for i := 0 to Length(NewArr)-1 do

[bytebites]

Code: Pascal  [Select][+][-]

1. for i in NewArr do writeln(i);