function setAllRecords(sr_start, sr_step) {

  sr_end = sr_start + sr_step;
  // set or unset checkboxes depending on the status of sr_set
  for (var i = sr_start; i < sr_end; i++) {
    sr_nr = "r" + i;
    document.getElementById(sr_nr).checked = !sr_set.disabled;
  }
  
  if(sr_set.disabled) {
    //    count = 'alle';
    txt = 'alle';
    sr = 0;
  }
  else {
    txt = sr_step;
    sr = sr_step;
  }

  sr_set.disabled = !sr_set.disabled
  //  document.all.count.innerText = value;
  document.getElementById('count').innerText = txt;
  document.getElementById('sr').value = sr;
}

function updateGraphs(sr_start, sr_step) {

  sr_end = sr_start + sr_step;
  url_graph = '&opt_rs=1';
  // set or unset checkboxes depending on the status of sr_set
  for (var i = sr_start; i < sr_end; i++) {
    sr_nr = "r" + i;
    if(document.getElementById(sr_nr).checked) url_graph = url_graph + '&' + sr_nr + '=1';
  }
  url_graph = document.getElementById('graph_img_img').src + url_graph;
//  alert(url_graph);
  document.getElementById('graph_img_img').src = url_graph;

}