function eis_get_daily_data, files, param_str, param_index, bintab, maxr, minr, basetime, endtime

    max_str = 'TDMAX' + strtrim(string(param_index), 2)
    min_str = 'TDMIN' + strtrim(string(param_index), 2)

    num_files = n_elements(files)
;    print,'NUM FILES ',num_files
    num_files = num_files-1
    last_file = num_files

    if num_files eq 0 then begin
        data = reform(eis_read_fits_data(files[0], param_str, bintab, header=header))

        basetime = fxpar(header, 'UT_START',count=count)
        if count eq 0 then begin
            basetime = fxpar(header, 'DATE_OBS')
        endif

;        print, 'BASE TIME', basetime
        endtime = fxpar(header,'DATE_END')
;        print, 'END TIME ', endtime
        maxr = fxpar(header,max_str)
        minr = fxpar(header,min_str)
        return,data
    endif

    for i = 0, num_files do begin
        if i eq 0 then begin
            data = reform(eis_read_fits_data(files[i], param_str, bintab, header=header))
            data_arr = [data]
            basetime = fxpar(header, 'UT_START',count=count)
            if count eq 0 then begin
;                print, 'Using DATE_OBS'
                basetime = fxpar(header, 'DATE_OBS')
            endif
;;;            print,files[i],i,' BASETIME ',basetime
            maxr = fxpar(header,max_str)
            minr = fxpar(header,min_str)
        endif else begin
            data = reform(eis_read_fits_data(files[i], param_str, bintab, header=header))
            if i eq last_file then begin
                endtime = fxpar(header,'DATE_END')
;;;;               print, files[i],i,' END TIME ', endtime
            endif
            data_arr = [data_arr,data]
            mx = fxpar(header,max_str)
            mn = fxpar(header,min_str)
            if mx gt maxr then maxr = mx
            if mn lt minr then minr = mn
        endelse
    endfor
    return,data_arr
end