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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt'>Hi All,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>I want to do a time query over multiply hdf5 files as following:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>import yt<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>from glob import glob<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>fns = glob(‘flash_hdf5_plf_*’)<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>data = []<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>for fn in fns:<o:p></o:p></span></p><p class=MsoNormal style='text-indent:10.15pt'><span style='font-size:11.0pt'>ds = yt.load(fn)<o:p></o:p></span></p><p class=MsoNormal style='text-indent:10.15pt'><span style='font-size:11.0pt'>pt = ds.point([0,0,0])<o:p></o:p></span></p><p class=MsoNormal style='text-indent:10.15pt'><span style='font-size:11.0pt'>data.append([ds.parameters[‘time’], pt.mean(‘tele’)])<o:p></o:p></span></p><p class=MsoNormal style='text-indent:10.15pt'><span style='font-size:11.0pt'>ds.close()<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>print data<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>At the beginning, it takes about 1s to process each file. But later, it becomes slower and slower. Finally, 100 files cost 10 minutes, much large than 1s*100. I guess maybe the database is not fully closed. When I try ds.field_info() after ds.close(), it still displays the field information. Does anyone have the same problem?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt'>Yingchao<o:p></o:p></span></p></div></body></html>