EIS Mapper Software


"EIS mapper" is a way of displaying the location of EIS rasters by over-plotting them on a full disk image (typically an EUV image from AIA or EIT). By doing this for every day of the mission one can fairly quickly identify useful data-sets based on the feature they were pointed at (e.g., active regions, coronal holes, etc.), by simply clicking through the images one-by-one.

Please visit the EIS Mapper webpage (https://eismapper.pyoung.org) to see the output from the software below.

Ken Dere originally presented the EIS data in this way, and referred to it as "EIS mapper". His website is no longer available, however, so the present webpage describes IDL software that produces webpages in a similar style.


Step 0: Getting started

All software is written in IDL and is available in the Hinode/EIS branch of Solarsoft.

First, create a directory in which you want to store the EIS Mapper data, and then point to it with the environment variable $EIS_MAPPER. For example, if you want to use the directory $HOME/my_eis_mapper, then put the following line in your IDL Startup file:

setenv,'EIS_MAPPER=$HOME/my_eis_mapper'

Step 1: Preparing EIS data

The first step in the process is to create save files containing information about the EIS observations. This is done for individual years with, e.g.:

IDL> eis_mapper_obs_str, year=2011

The save files go to $EIS_MAPPER/data, with a separate file for each month. In each save file is a structure that has been created with the routine eis_obs_structure.

Step 2: Calendar files

To create a html page containing a calendar listing all the days for which maps are available, do:

IDL> eis_mapper_year, 2011

which creates the file $EIS_MAPPER/html/2011/index.html. If a day in the calendar has a link, then it means a map page is available.

To process all years of the EIS mission, repeat the above call for all years from 2006 onwards. 

WARNING: this step can take quite a long time. Typically an hour.

Step 3: Create index file

After you have run eis_mapper_year for all years of the mission you can create an index file with a list of all the years for which there are data:

IDL> eis_mapper_year_index

This creates the file $EIS_MAPPER/html/index.html.


Setting up a cron job

I keep my eis_mapper pages up-to-date with a weekly cron job. I have the shell script eis_mapper_weekly.csh which starts up the IDL script, called eis_mapper_weekly.pro. (For the purposes of displaying these files in a web browser, I've appended ".txt" to the filenames. These should be removed if you download the files.)

In addition to the weekly cron job, I also have a monthly one. This is required because sometimes there is a delay in an EIS file being processed, and it may not appear in the database for a few weeks. The monthly job is run on the 28th of the month and regenerates the eis_mapper files for the current and previous months. The script eis_mapper_monthly_refresh.csh executes the IDL script eis_mapper_monthly_refresh.pro, which simply removes all the files for the current and previous months. The weekly script (see above) is then run again to regenerate the files for these two months.

The entries in my cron file are:

0 2 * * 0 ~/scripts/idl/eis_mapper_weekly.csh
0 6 28 * * ~/scripts/idl/eis_mapper_monthly_refresh.csh
30 6 28 * * ~/scripts/idl/eis_mapper_weekly.csh

Troubleshooting

I had a problem with my cron job that resulted in no results for one month. In this case the solution is to run eis_mapper_obs_str again on that month:

IDL> eis_mapper_obs_str,/overwrite,year=2021,month=5

Then create the webpages with:

IDL> eis_mapper_year,2021
IDL> eis_mapper_year_index

If you're concerned that some of the webpages aren't correct and you want to redo them, then you have to re-write the entire year by doing:

IDL> eis_mapper_year,2021,/overwrite
IDL> eis_mapper_year_index

The EIS obs structure

The routine eis_obs_structure is a convenient way of quickly querying the EIS databases from the IDL command line and returning the results in an IDL structure. Some information about it is given in Section 4 of EIS Software Note No. 19. The routine eis_mapper_obs_str that is run in Step 1 calls eis_obs_structure, and any of the eis_obs_structure keywords can be passed to eis_mapper_obs_str.

Customization

The above procedure will show you the results for the entire EIS database. It is possible to show results for a subset of the database by modifying the EIS data that is saved in Step 1. Two examples are illustrated below.

Only show the results for a single EIS study

Suppose you only want to show the results for the study "Atlas_60" (a spectral atlas study that is run regularly). You can search on a  study acronym with eis_obs_structure, but it's much quicker to search on the raster acronym. To find the latter, start the GUI routine eis_xstudy:

IDL> eis_xstudy

Search for your study and click on it. The raster window at the bottom of the window now shows information about the raster, including the acronym (in this case it is also "Atlas_60"). You can now do:

IDL> eis_mapper_obs_str, year=2011, rast_acr='atlas_60', outdir='~/eis_mapper_atlas_60'

Note that I set an output directory so that the results don't overwrite the standard EIS mapper results.

With the new observation structure save files, you can perform Step 2, adding the outdir optional input:

IDL> eis_mapper_year, 2011, outdir='~/eis_mapper_atlas_60'

NOTE: if you use rast_acr='atlas' (for example) then the routine will pick all rasters that have atlas in their name.

Require specific wavelengths to be observed

You may be interested in a specific emission line or plasma diagnostic and would like to display only those rasters that contain these lines. An example is the Fe XIII 202.04/203.82 density diagnostic.

The routine eis_mapper_obs_str accepts the keyword "wvl" allowing a set of wavelengths to be input:

IDL> eis_mapper_obs_str,year=2011,wvl=[202.04,203.82],outdir='~/eis_mapper_fe13'
IDL> eis_mapper_year,2011,outdir='~/eis_mapper_fe13'

Note that the routine checks if the specified wavelengths lie within any of the spectral windows, so the window does not have to be centered on the wavelength.

Spectral atlas observations

Spectral atlas observations take the complete wavelength range of EIS, and thus offer the full range of spectral diagnostics. The commands below show how to restrict the EIS mapper output to only spectral atlas observations for 2013:

IDL> eis_mapper_obs_str,year=2013,outdir='~/eis_mapper_atlas',/atlas,fovx=20,/narrow
IDL> eis_mapper_year, 2013,outdir='~/eis_mapper_atlas'

The "fovx" keyword requires the field-of-view in the X-direction to be 20 arcsec or larger. This basically removes any single-exposure data, or sit-and-stare sequences. The "/narrow" keyword means that only narrow-slit datasets are returned, i.e., 1" or 2" slit data.

Other options

Other options for eis_mapper_obs_str are:

xcen: 2-element array specifying a range of xcen values. Only rasters within this range are returned.
ycen: 2-element array specifying a range of ycen values.
/slot: only return slot data (i.e., 40" or 266" slit data).
slit_index: specify the index of particular EIS slit. 0 corresponds to the 1" slit, 1 to the 266" slit, 2 to the 2" slit and 3 to the 40" slit.


Page maintained by Dr Peter R Young.