(a) The petition may be accompanied by the certificate of a physician, qualified examiner, psychiatrist, advanced practice psychiatric nurse, or clinical psychologist which certifies that the respondent is subject to involuntary admission on an inpatient basis and which contains the other information specified in Section 3-602.
     (b) Upon receipt of the petition either with or without a certificate, if the court finds the documents are in order, it may make such orders pursuant to Section 3-703 as are necessary to provide for examination of the respondent. If the petition is not accompanied by 2 certificates executed pursuant to Section 3-703, the court may order the respondent to present himself for examination at a time and place designated by the court. If the petition is accompanied by 2 certificates executed pursuant to Section 3-703 and the court finds the documents are in order, it shall set the matter for hearing.