How does one write data to a text file in a DC sweep?  I have attached the code I frequently use for writing data in transient analysis.  It works great.  The difference is that in a DC sweep I can't use the @timer function.  If I use a similar code in a DC sweep without the timer line then I just get one data point.  Can someone suggest modifications that will record the entire DC sweep?

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`include "disciplines.vams"
`include "constants.vams"

module sink1(v1);
   electrical v1;                                                  //node voltage to write
   parameter string file_name = "filename.tbl";     //file name to write to
                                                                        //strings only work in some versions of verilogA
                                                                        //hardcode the filename if necessary
   parameter real T_step = 1e-9;                         //time step for writing data.
   parameter real T_off = 0;                                //time to wait before starting
   integer file_ptr;                                               //pointer to file_name

   analog begin
       @( initial_step ) begin
          file_ptr=$fopen(file_name);
       end

       @(timer(T_off,T_step)) begin                        //at each T_step write the node voltage
         $fwrite(file_ptr, "%e %e\n", $abstime, V(v1));
       end

       @ (final_step) begin
         $fclose(file_ptr);
       end
   end
endmodule
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