DRMS command-line access
The DRMS provides command-line utilities for access data. The most useful are described here, but the reader can also look at the JSOC wiki for further commands and details. You will also find below the commands for accessing the 12 minute cadence Level-1 AIA FITS images.
show_series: a DRMS utility to determine which data series are available
Display help menu
> show_series --help
List all available DRMS data series at the GDC-SDO
> show_series
List all available DRMS data series containing "hmi" as part of the name
> show_series "hmi"
List all available DRMS data series containing "aia" as part of the name
> show_series "aia"
show_info: a DRMS utility for accessing the meta-data (i.e. keywords) and segment (i.e. FITS image) information
Display the help menu to produce a long list of useful options; please explore them all
> show_info --help
Print the "JSOC Series Definition" for e.g. aia.lev1 series. This is a very useful command to learn about a particular DRMS series. It will list all the all the keywords available along with a short description of each. It also lists the segment(s) (i.e. image) information for the series such as the segment name (required for searching) as well as the size of the size and compression information.
> show_info "aia.lev1" -j
Get statistics for the HMI continuum data series; this gives an idea of the data coverage in time that is available
> show_info "hmi.Ic_45s" -s
Count how many data records are available for the HMI LOS Magnetograms
> show_info "hmi.M_45s" -c
Display the T_REC keyword for the very first available frame for the Dopplergrams
> show_info "hmi.V_45s" key=T_REC n=1
Check online status for the segment (i.e. FITS image) for the first frame: Y => online or NA=> offline
> show_info "hmi.V_45s" key=T_REC n=1 -o
Display the T_REC keyword for the very last available frame
> show_info "hmi.V_45s" key=T_REC n=-1
Display the keywords T_REC and WAVELNTH for AIA level-1 data series, as well as check online status (-o flag) for the latest 3 records at the wavelength 1600 A
> show_info "aia.lev1[?WAVELNTH=1600?]" n=-3 key=WAVELNTH,T_REC -o
Display online location of HMI Dopplergram FITS image at specified date/time
> show_info "hmi.V_45s[2010.12.13_23:53:15_TAI]" -P seg=Dopplergram
Display retention time for a particular segment (i.e. FITS image); once the retention expires, SUMS will delete image.
> show_info "hmi.V_45s[2010.12.13_23:53:15_TAI]" -R
DRMS command-line access to 12-minute cadence Level-1 FITS images
The DRMS utility show_info is used to get the locations of the 12-min cadence FITS images. It is suggested you bookmark this page and cut-and-paste everytime you need this command. Try the following example
> show_info "aia.lev1[2010-12-01T00:00:01Z/2h][?WAVELNTH=131?][?mod(cast(T_REC as bigint)-34,720)<=12?]" -P seg=image_lev1 key=T_REC,WAVELNTH
which gives you a list containing
- full paths to the level-1 FITS images for which the above command requires the "-P" flag and the "seg=image_lev1" option (seg is short for segment or FITS image). To determine the segment name (image_lev1 in this case) of various series, print the jsoc series definition with "show_info aia.lev1 -j" and look at the available segments.
- T_REC time-stamps for each segment (image) are listed by specifing key=T_REC. The description of T_REC is also in the jsoc series definition (see it is listed as a primary key)
- a time range that is determined by the first "square-bracket" search criteria [2010-12-01T00:00:01Z/2h]. It starts from a date/time of 2010-12-01T00:00:01Z and ends after 2 hours, hence the /2h. Other options include m for minute and h for hour. You can also specify start and end times such as [2010-12-01T00:00:01Z-2010-12-01T01:48:11Z]. Note the time criteria in the square brakets is not flanked by question marks "[?..?]" whereas the others (to be described shortly do). This is because it is a primary key which can be seen in the jsoc series definition.
- the wavelengths are listed by specifying key=WAVELNTH. In addition, we have chosen to select only the 131 A wavelength by including a search criteria of [?WAVELNTH=131?]. If you are interested in a different wavelength, then choose a different number, or if you are interested in several wavelengths, then you can do something like [?WAVELNTH=171 and WAVELNTH=193?] for 171 A and 193 A.
- the criteria for selecting the 720 s (i.e 12-min) cadence is [?mod(cast(T_REC as bigint)-34,720)<=12?]]; 34 is a number to get images starting near the beginnning of each hour (for the 1600A and 1700A data change this to 44); 720 corresponds to the 720s (12min) cadence; 12 corresponds to the full cadence in seconds of the wavelength you are looking at i.e. 12s for 131 A
- For the 1600A, 1700A, or 4500A data, the command has to be modified to reflect that these series have a full cadence of 24s, 24s, and 3600s respectively. Also, the value 34 changes to 44 for the 1600 A and 1700 A wavelengths.
Once you are comfortable with all the various options, the most useful command may be to produce a list containing just the paths to the segemets (FITS images), which can then be easily read into any scientific code you many have. To do this, you would omit "key=T_REC,WAVELNTH" from the above command and include the "-q" flag (quiet) so list titles are printed to screen. The screen output can then easily be redirected to some text file.
> show_info "aia.lev1[2010-12-01T00:00:01Z/2h][?WAVELNTH=131?][?mod(cast(T_REC as bigint)-34,720)<=12?]" -qP seg=image_lev1 > aia.lev1.FITS.files.list.txt