function init_stuff() {
    dataobj=document.getElementById('output');
}

function go() {
    //preparing parameters
    var params_list = ['rep_copy', 'rep_const', 'rep_horiz_part', 'rep_surrog', 'rep_vert_part', 
		       'rep_unnest', 'rep_nest', 'rep_selfjns', 'rep_denorm', 'rep_fus', 'rep_atom', 'rep_synth',
		       'avrg_nest_depth_val', 'avrg_nest_depth_dev', 'avrg_subel_num_val', 'avrg_subel_num_dev',
		       'avrg_pathlen_val', 'avrg_pathlen_dev', 'avrg_elems_val', 'avrg_elems_dev',
		       'avrg_args_val', 'avrg_args_dev', 'inst_card', 'inst_max_len', 'inst_max_num'];

    var url = "/generate.php?";
    for (i=0; i<params_list.length; i++) {
	parelem = document.getElementById(params_list[i]);
	if (parelem) {
	    if (i > 0) { url += '&'; }
	    url += params_list[i] + '=' + parelem.value;
	}
    }
    parelem = document.getElementById("join_kind");
    if (parelem && parelem.options) {
	url += "&join_kind=" + parelem.options[parelem.selectedIndex].value;
    }

    sendRequest(url);
}

function reset_form() {
    dataobj=document.getElementById('output');
    if (dataobj) { dataobj.innerHTML=''; }
}