To download TRACE data to NRL from IDL, log on to gravity and enter Solarsoft. For your time period do:
IDL> get_trace_data,'11-APR-2010 11:00','11-APR-2010 14:00'
and the data will automatically be downloaded.
The TRACE catalogue is stored in \$SSWDB and comes in three forms: tcl (standard catalogue), tcs (short catalogue) and tce (engineering catalogue).
Reading and displaying the catalogue files is done as follows:
trace_cat,'31-may-98','1-jun-98',cat
more, trace_list_index(cat)
and the index and data arrays can be loaded as follows:
trace_cat2data,cat,index
ss=trace_sswhere(cat)
trace_cat2data,cat(ss),index,data
The first step is to create an array of filenames, e.g.:
files=trace_files('31-may-98','1-jun-98')
The data can then be read into IDL as follows
read_trace,files,-1,index
ss=trace_sswhere(index)
read_trace,files,ss,index,data
If you only want to extract images every 5 minutes, then try doing:
read_trace,files,-1,index
ss=trace_sswhere(cat)
ss_out=trace_5min_files(ss,index)
(this is one of my routines). The output ss\_out can then be used in place of ss in the call to read\_trace.
Quite a large proportion of TRACE data is almost unusable because of the spikes in the data. One can avoid choosing this data by making use of the .img_dev tag in the index structure, e.g.,
ss=where( index.img_dev le 70. )
To use trace_prep, you need to have the dark current files. These are distributed through $SSWDB.
The standard call to trace_prep is
IDL> trace_prep,index,data,outindex,outdata,/unspike,/destreak,/deripple
This can be done with
IDL> trace_align_cube, itrace, dtrace, index, data
where itrace and dtrace are the initial index and data fields, and index and data are the outputs.