moving a few columns/rows from table a to b

[#1]

Clear Symbols();
// Open a file dialog to choose the text file
txtFilePath = Pick File("Choose a text file", {"Text Files|*.txt"});
 
// Check if a file was selected
If(txtFilePath != "", 
    // Convert the file path to ensure it's in the correct format
	txtFilePath = Convert File Path(txtFilePath);
 
    // Import the text file into a new JMP table
	dt1 = Open(
		txtFilePath,
		Delimiter("\t") // Change delimiter if necessary
	);
 
    // Specify the row to use for column names (e.g., row 1)
	columnNamesRow = 16;
 
    // Specify the columns to extract (e.g., columns 1, 2, 3)
	columnsToExtract = {1, 17, 18, 22}; // Adjust column indices as needed
 
	// Extract the column names from the specified row and columns
   
	columnNamesList = {};
	For(j = 1, j <= N Items(columnsToExtract), j++,
		colIndex = columnsToExtract[j];
		columnNamesList[j] = :Column(colIndex)[columnNamesRow];
	);
    
   
    // Create a new JMP table with the extracted column names
	dt2 = New Table("Converted Table");
 
    
  
	For(i = 1, i <= N Items(columnNamesList), i++,
		dt2 << New Column(Char(columnNamesList[i]), Character); // Adjust column type as needed
	);
 
    // Specify the rows to extract (e.g., rows 2 to 10)
	startRow = 17;
	endRow = 65;
//
	// Loop through the specified rows and add them to the JMP table
	For(i = startRow, i <= endRow, i++,
		dt2 << Add Rows(1);
		For(j = 1, j <= N Items(columnsToExtract), j++,
			colIndex = columnsToExtract[j];
           
			dt2:Column(j)[i - startRow + 1] = dt1:Column(colIndex)[i];
		);
	);
 
    // Close the imported table
	Close(dt1);
, 
    // If no file was selected, show a message
	Show Message("No file selected.")
);

I am getting a same error messages: 

Scoped data table access requires a data table column or variable at row 1 in access or evaluation of 'dt1:Column' , dt1:Column( colIndex ) /*###*/

at line 49

[#2]

Syntax for referencing to columns is incorrect (you are combining Column() and As Column() (the table:column syntax)).

Changing

dt2:Column(j)[i - startRow + 1] = dt1:Column(colIndex)[i];

to

Column(dt2, j)[i - startRow + 1] = Column(dt1, colIndex)[i];

might work.

Also, there might be easier methods to do what you want to achieve but it would require for us to see an example file and the wanted result.

[#3]

As Jarmo indicates, for some of the steps, JMP provides pre-defined modules.

By using such modules:

• the code gets shorter and easier to understand
• JMP handles the data types automatically
• the execution is much faster

txtFilePath = "$SAMPLE_IMPORT_DATA/Animals_line3.txt";
columnNamesRow = 3;
columnsToExtract = {"species", "miles"};
startRow = 2;
endRow = 10;

dt1 = Open( txtFilePath, 
	Import Settings( Labels( 0 ) )
);
wait(0); //let JMP relax before it continues with the next steps

if(columnNamesRow>1, dt1 << delete rows( 1 :: (columnNamesRow - 1) ));
dt1 << move up; 

dt2 = dt1 << Subset(
	Rows( startRow :: endRow ),
	columns( columnsToExtract )
);