small update. Changing arguments into keywords for dustem_set_data and the subse…

…quent effects on the example procedures

small update. Changing arguments into keywords for dustem_set_data and the subse…
…quent effects on the example procedures
Ilyes Choubani
1 parent c19cb3d1
Showing 13 changed files with 259 additions and 235 deletions Show diff stats
src/idl/dustem_activate_plugins.pro
src/idl/dustem_check_data.pro
src/idl/dustem_fit_ext_example.pro
src/idl/dustem_fit_ext_pol_example.pro
src/idl/dustem_fit_intensity_example.pro
src/idl/dustem_fit_intensity_mbb_example.pro
src/idl/dustem_fit_polarization_example.pro
src/idl/dustem_fit_sed_ext_pol_example.pro
src/idl/dustem_mask_data.pro
src/idl/dustem_myisrf_example.pro
src/idl/dustem_set_data.pro
src/idl/dustem_stellarpopisrf_example.pro
src/idl/dustemwrap_plot.pro
@@ -76,17 +76,19 @@ endelse
 ;IF /avoid is used the specified scopes are avoided. They're considered when /avoid is missing.
 ;using '**' so not to write the entire scope
 dustem_run_plugins, p_dim ,param_descs, param_values, param_func, ['*STELLAR*','*REPLACE*','*ISRF*'], avoid=1
-;stop
+
 ;=== The line below makes fawlty go Segmentation fault. st is undefined at that stage
 ;=== it would run fine if avoid was set to 1
+;IC: I think the segmentation fault comes from the fact that the user wants to use models that have the /pol keyword in the GRAIN.DAT file without being in polarization mode.
 dustem_run_plugins, p_dim ,param_descs, param_values, param_func, ['*STELLAR*','*ISRF*'] ,dustem_run=1,st=st ;dustem output is available at this step.
  
 ;added this small condition to ensure that dustem is run
 ;(if no ISRF plugin is used)  
-if ~isa(st) then begin
-    st=dustem_run(p_dim)
-    !dustem_current=ptr_new(st)
-endif
+; if ~isa(st) then begin
+;     st=dustem_run(p_dim)
+;     !dustem_current=ptr_new(st)
+; endif
+;THE ABOVE CONDITION IS UNNECESSARY SINCE DUSTEM IS CALLED ABOVE WHETHER PLUGINS ARE RUN OR NOT.
  
 dustem_run_plugins, p_dim ,param_descs, param_values, param_func, ['*REPLACE*']
  
-PRO dustem_check_data,data_sed,data_ext,sed,ext,polext,polsed,polfrac,psi_em,qsed,used,qext,uext,psi_ext,fpolext
+PRO dustem_check_data, data_sed, $
+                       data_ext, $
+                       sed=sed, $
+                       ext=ext, $
+                       polext=polext, $
+                       polsed=polsed, $
+                       polfrac=polfrac, $
+                       psi_em=psi_em, $
+                       qsed=qsed, $
+                       used=used, $
+                       qext=qext, $
+                       uext=uext, $
+                       psi_ext=psi_ext, $
+                       fpolext=fpolext
  
 ;+
 ; NAME:
 ;    dustem_check_data
 ;
 ; PURPOSE:
-;    Verify that the input data conforms to what DustEMWrap requires
+;    Clean and modify the input DustEMWrap structure to meet the requirements of DustEMWrap. 
+;    This is important for the subsequent internal handling/fitting of data. 
 ;
 ; CATEGORY:
 ;    DustEMWrap, Mid-Level, Distributed, Initialization
 ;
 ; CALLING SEQUENCE:
-;    dustem_check_data,data_sed,data_ext,sed,ext,polext,polsed,polfrac,psi_em,qsed,used,qext,uext,psi_ext,fpolext,[/help]
+;    dustem_check_data,data_sed,data_ext,sed=sed,ext=ext,polext=polext,polsed=polsed,polfrac=polfrac,psi_em=psi_em,qsed=qsed,used=used,qext=qext,uext=uext,psi_ext=psi_ext,fpolext=fpolext,[/help]
 ;
 ; INPUTS:
-;    data_sed : Emission dustemwrap structure
-;    data_ext : Extinction dustemwrap structure
+;    data_sed : Emission DustEMWrap structure
+;    data_ext : Extinction DustEMWrap structure
 ;
 ; OPTIONAL INPUT PARAMETERS:
 ;    None
 ;
-; OUTPUTS:
-;    ## adapting the data structures to the format used by the fitting algorithm 
-;    sed : emission formatted structure 
-;    ext : extinction formatted structure
-;    polext : polarized extinction formatted structure
-;    polsed : polarized emission formatted structure 
-;    polfrac : fractional polarized emission formatted structure
-;    psi_em  : emission polarization angle formatted structure 
-;    qsed : stokesQ emission formatted structure
-;    used : stokesU emission formatted structure
-;    qext : stokesQ extinction formatted structure
-;    uext : stokesU extinction formatted structure
-;    psi_ext : extinction polarization angle formatted structure
-;    fpolext : fractional extinction polarization formatted structure
+; OUTPUTS: 
+;    sed : modified emission structure 
+;    ext : modified extinction structure
+;    polext : modified polarized extinction structure
+;    polsed : modified polarized emission structure 
+;    polfrac : modified fractional polarized emission structure
+;    psi_em  : modified emission polarization angle structure 
+;    qsed : modified StokesQ emission structure
+;    used : modified StokesU emission structure
+;    qext : modified StokesQ extinction structure
+;    uext : modified StokesU extinction structure
+;    psi_ext : modified extinction polarization angle structure
+;    fpolext : modified fractional extinction polarization structure
 ;
 ; OPTIONAL OUTPUT PARAMETERS:
 ;    None
@@ -53,12 +66,15 @@ PRO dustem_check_data,data_sed,data_ext,sed,ext,polext,polsed,polfrac,psi_em,qse
 ;    None
 ;
 ; EXAMPLES
-;    dustem_check_data,data_sed,data_ext,sed,ext,polext,polsed,polfrac,psi_em,qsed,used,qext,uext,psi_ext,fpolext,[/help]
-;
+;    dustem_check_data,data_sed,data_ext,sed=sed,ext=ext,polext=polext,polsed=polsed,polfrac=polfrac,psi_em=psi_em,qsed=qsed,used=used,qext=qext,uext=uext,psi_ext=psi_ext,fpolext=fpolext,[/help]
+;    dustem_check_data,/help
 ; MODIFICATION HISTORY:
-;    Written I Choubani 2022
+;    Written IC 2022
 ;    Evolution details on the DustEMWrap gitlab.
 ;    See http://dustemwrap.irap.omp.eu/ for FAQ and help.   
+; COMMENTS:
+;    Might still need a bit of cleaning. I am unsure of the availability of covariance data in polarized extinction.
+;    Still regarding extinction, some of the error messages haven't been mirrored correctly with respect to the emission block.
 ;-
  
  
@@ -202,8 +218,7 @@ IF KEYWORD_SET(data_sed) THEN BEGIN
  
     ;Generation of POLFRAC,POLSED and PSI data by default   
     ;Testing on the presence of covariances otherwise an error is returned
-    ;The testing happens here because covariances are needed for the error estimation of P,p and PSI.   
-     
+    ;The testing happens here because covariances are needed for the error estimation of P,p and PSI. (Also cannot test before because we're not in !run_pol mode) 
     tstcovu = where((data_sed(testu).sigmaIU) EQ la_undef() or (data_sed(testu).sigmaQU) EQ la_undef(), ctcovu)
     if ctcovu NE 0  then BEGIN
         ;message, 'Covariance data is missing in StokesU data. Data, errors and covariances do not match. Aborting...',/continue
@@ -253,11 +268,9 @@ IF KEYWORD_SET(data_sed) THEN BEGIN
 ENDIF
  
  
-;EXTINCTION HASN'T BEEN TREATED YET 
-
-
-;SMALLL ISSUE .. POLEXTFRAC is not present. Let's create it for completness
-
+;EXTINCTION
+;
+;Covariances?... 
 IF KEYWORD_SET(data_ext) THEN begin
  
     ans=''
@@ -170,7 +170,7 @@ ext=read_xcat(file,/silent)
  
 ;=== HERE WE SET THE DATA SO THAT THE COMPUTE_ FUNCTIONS BELOW HAVE
 ;=== THE NECESSARY FIELDS AND INFORMATION
-dustem_set_data,sed,sed,ext,ext 
+dustem_set_data,m_fit=m_fit,m_show=m_show,x_fit=ext,x_show=ext 
  
 ;== SET INITIAL VALUES AND LIMITS OF THE PARAMETERS FOR THE FIT 
 ;== AND ACTIVATE ANY PLUGINS 
@@ -217,9 +217,9 @@ IF keyword_set(fits_save_and_restore) THEN BEGIN
   ;==== plot result taken from the saved fits table
   res=*(*!dustem_fit).CURRENT_PARAM_VALUES
   IF !dustem_noobj THEN BEGIN
-     dustemwrap_plot_noobj,res,dustem_st,xr=xr,/xstyle,yr=yr,/ysty,/ylog,/xlog,title=tit+' (From Saved FITS file)'
+     dustemwrap_plot_noobj,res,st=dustem_st,xr=xr,/xstyle,yr=yr,/ysty,/ylog,/xlog,title=tit+' (From Saved FITS file)'
   ENDIF ELSE BEGIN
-    dustemwrap_plot,res,dustem_st,xr=xr,/xstyle,yr=yr,/ysty,/ylog,/xlog,title=tit+' (From Saved FITS file)'
+    dustemwrap_plot,res,st=dustem_st,xr=xr,/xstyle,yr=yr,/ysty,/ylog,/xlog,title=tit+' (From Saved FITS file)'
   ENDELSE
   IF keyword_set(wait) THEN BEGIN
      message,'Saved the results as FITS in the file: '+fits_save_and_restore+', and made a plot using the data in this file',/info
@@ -113,7 +113,7 @@ use_polarization=0.   ;default is no polarization in models
 use_window=2       ; default graphics window number to use for plotting the results
 use_verbose=0
 if keyword_set(verbose) then use_verbose=1
-use_Nitermax=5        ; maximum number of iterations for the fit
+use_Nitermax=1        ; maximum number of iterations for the fit
 IF keyword_set(Nitermax) THEN use_Nitermax=Nitermax
  
 dustem_define_la_common
@@ -191,7 +191,7 @@ ENDIF
 ;=== THE NECESSARY FIELDS AND INFORMATION
 ;== note that m_fit and m_show do not exist -- this is deliberate
 ;== since we are not treating emission data
-dustem_set_data, m_fit,m_show,ext,ext
+dustem_set_data, m_fit=m_fit,m_show=m_show,x_fit=ext,x_show=ext
  
 ;== SET INITIAL VALUES AND LIMITS OF THE PARAMETERS FOR THE FIT 
 ;== AND ACTIVATE ANY PLUGINS (HENCE WE NEED TO DO THIS BEFORE THE COMPUTE_ CALLS)
@@ -206,7 +206,7 @@ dustem_init_params,use_model,pd,iv,fpd=fpd,fiv=fiv,ulimed=ulimed,llimed=llimed,u
 if not keyword_set(ext_file) then begin
 ;== GENERATE THE DATA USING THE MODEL AND TRUE VALUES
    ext.EXT_I = dustem_compute_ext(true_vals,st=st)
-   toto = dustem_compute_stokext(true_vals,st=st,qext_spec=dustem_qext,uext_spec=dustem_uext)
+   toto = dustem_compute_stokext(true_vals,st=st)
    ext.EXT_Q = toto[0]
    ext.EXT_U = toto[1]
  
@@ -229,7 +229,7 @@ tol=1.e-10
 ;=== INFORMATION TO MAKE THE PLOTS
 ;=== _x/_extinction means extinction plots, _m/_emissions means emission plots
 xr_x=[0.01,30]
-yr_fpolext=[1.00E-10,30]
+yr_fpolext=[1.00E-10,50]
  
 ;yr_fpolext=[1e-4,30]
 tit='Dust Optical Depth'
@@ -247,7 +247,7 @@ if keyword_set(wait) then begin
    message,'Time taken [sec]: '+sigfig(t2-t1,2,/sci),/info
    wait,wait
 end
-
+stop
 IF keyword_set(fits_save_and_restore) THEN BEGIN
    message,'Writing out results structure: '+fits_save_and_restore,/info
    dustem_write_fits_table,filename=fits_save_and_restore,help=help
@@ -257,6 +257,7 @@ IF keyword_set(fits_save_and_restore) THEN BEGIN
   dustem_read_fits_table,filename=fits_save_and_restore,dustem_st=dustem_st
   ;==== plot result taken from the saved fits table
   res=*(*!dustem_fit).CURRENT_PARAM_VALUES
+  !dustem_end=-1; subsequent calls to the fit. 0 is intialization an 1 is for the last iteration. It's initialized to 0 after the creation of the fits file.
   IF !dustem_noobj THEN BEGIN
      dustemwrap_plot_noobj,res,st=dustem_st,xr=xr,/xstyle,yr=yr,/ysty,/ylog,/xlog,title=tit+' (From Saved FITS file)'
   ENDIF ELSE BEGIN
@@ -296,7 +296,7 @@ IF count NE 0 THEN sed[ind].sigmaII=(0.2*sed[ind].StokesI)^2
 ;== SET THE OBSERVATIONAL STRUCTURE
 ;== sed is passed twice in the call -- the first occurrence is the SED that you
 ;== wish to fit, the second occurrence is the SED that you wish to visualise. 
-dustem_set_data,sed,sed
+dustem_set_data,m_fit=sed,m_show=sed
  
 ;== SET INITIAL VALUES AND LIMITS OF THE PARAMETERS THAT WILL BE
 ;== ADJUSTED DURING THE FIT
@@ -194,7 +194,7 @@ IF count NE 0 THEN sed[ind].sigmaII=(0.2*sed[ind].StokesI)^2
 ;== SET THE OBSERVATIONAL STRUCTURE
 ;== sed is passed twice -- the first occurrence is the SED that you
 ;== wish to fit, the second occurrence is the SED that you wish to visualise. 
-dustem_set_data,sed,sed
+dustem_set_data,m_fit=sed,m_show=sed
  
 ;== SET INITIAL VALUES AND LIMITS OF THE PARAMETERS THAT WILL BE
 dustem_init_params,use_model,pd,iv,fpd=fpd,fiv=fiv $
@@ -164,7 +164,7 @@ sed=read_xcat(file,/silent)
 ;== SET THE OBSERVATIONAL STRUCTURE
 ;== sed is passed twice -- the first occurrence is the SED that you
 ;== wish to fit, the second occurrence is the SED that you wish to visualise. 
-dustem_set_data,sed,sed
+dustem_set_data,m_fit=sed,m_show=sed
  
  
  
@@ -217,7 +217,7 @@ ENDIF
  
 ;=== HERE WE SET THE DATA SO THAT THE COMPUTE_ FUNCTIONS BELOW HAVE
 ;=== THE NECESSARY FIELDS AND INFORMATION
-dustem_set_data,sed,sed,ext,ext 
+dustem_set_data,m_fit=sed,m_show=sed,x_fit=ext,x_show=ext 
  
 ;== SET INITIAL VALUES AND LIMITS OF THE PARAMETERS FOR THE FIT 
 ;== AND ACTIVATE ANY PLUGINS (HENCE WE NEED TO DO THIS BEFORE THE COMPUTE_ CALLS)
-   FUNCTION dustem_mask_data,data_struct,omit=omit,data_set=data_set,help=help
+FUNCTION dustem_mask_data, data_struct,       $
+                           filters,           $
+                           data_set=data_set, $
+                           default=default,   $
+                           help=help
+
 ;+
 ; NAME:
 ;    dustem_mask_data
 ; PURPOSE:
-;    Removing filters from a data structure.
+;    Set dataset values to la_undef() for specified filter/spectrum data in an input DustEmWrap data structure.
 ; CATEGORY:
 ;    DUSTEM Wrapper
 ; CALLING SEQUENCE:
-;    data_struct=dustem_mask_data(data_struct,omit=,data_set=)
+;    data_struct=dustem_mask_data(data_struct,filters,data_set=,/default)
 ; INPUTS:
-;    data_struct : SED Data structure formatted as outlined in the DustermWrap Users' Guide
-;    data_set : Array of character strings containing the different data sets to be filtered.
-;    ie: ['SED'],['QSED'],'USED'] or just ['QSED'] for example. The use of ['STOKESI','STOKESQ','STOKESU'] instead is equivalent.
-;    omit : Can be an array or list. In both cases it should contain the filter names as character strings. 
-;    ie: omit=['SPIRE1','SPIRE2'] for an array or omit=list(['SPIRE2','SPIRE1','PACS2'],['HFI5','HFI4']) for a list.
-;    When using a list, its shape (dimension) should be the number of elements of the data_set array.
-;    ie: Each dimension is an array of filters to be removed from the corresponding data set in the data_set array.
+;    data_struct : SED Data structure following the format explained in the DustermWrap Users' Guide
+;
+;    filters : Can be an array or list. In both cases it should contain the filter names as character strings. 
+;    ie: filters=['SPIRE1','SPIRE2'] for an array or filters=list(['SPIRE2','SPIRE1','PACS2'],['HFI5','HFI4']) for a list.
+;    When using a list, its shape (dimension) and the number of elements of the data_set array should be equal.
+;    Each dimension is an array of filters to be removed from the corresponding data set in the data_set array.
+;    ie: filters=list(['SPIRE2','SPIRE1','PACS2'],['LFI2','LFI3']) for datas_set=['STOKESI','STOKESQ']
 ; OPTIONAL INPUT PARAMETERS:
-;    None
+;    data_set : Array of character strings containing the different data sets to be filtered.
+;    ie: ['STOKESI','STOKESQ','STOKESU'] or just ['STOKESQ'] for example.
 ; OUTPUTS:
 ;    data_struct 
 ; OPTIONAL OUTPUT PARAMETERS:
 ;    None
 ; ACCEPTED KEY-WORDS:
-;    help                  = if set, prints this help
+;    help                  = if set, print this help
+;
+;    default               = if set, remove targeted filter/spectrum point(s) from datasets that depend on the filtered dataset(s).
+; EAMPLE
+;    masked_structure = dustem_mask_data(data_struct,['IRAS1','IRAS2'],data_set=['STOKESI'])  
 ; COMMENTS
-;   Both list and array entries for omit and hide keywords are allowed.
+;    IC:
+;    If a wavelength value is supplied instead of a filter name, the procedure masks for a spectrum point with that corresponding wavelength
+;    If the dataset array isn't supplied, all the datasets in the input data structure will be considered.
+;    If both filters and dataset are arrays, all mentioned filters will be masked from all mentioned datasets.
+;    This procedure does not change the shape of the output structure partly because dustem_check_data.pro does.
 ; MODIFICATION HISTORY:
-;    Written by IC 
+;    Written by IC 2022
 ;-
  
  
 IF keyword_set(help) THEN BEGIN
-  doc_library,'dustem_filter_data'
+  doc_library,'dustem_mask_data'
   goto,the_end
 ENDIF
  
-IF keyword_set(data_struct) and keyword_set(omit) THEN BEGIN
-
-    ;Array of filters present in dustem
-    filters_dustem=[((*!dustem_filters).(0).filter_names)]
+IF arg_present(data_struct) and arg_present(filters) THEN BEGIN
  
+    ;Array of filters present in dustem
+    filters_dustem=[((*!dustem_filters).(0).filter_names)]    
     for i=1L,n_elements(tag_names(*!dustem_filters))-1 do begin
         filters_dustem=[filters_dustem,((*!dustem_filters).(i).filter_names)] 
     endfor 
-    
     ;Array of filters present in data_struct
     filters_data = data_struct.filter
-    
     ;Tag names present in data_struct (to be able to test on the different data sets)
-    tagnames = tag_names(data_struct)
-   
-    
-    if typename(omit) EQ 'LIST' then ind0 = omit[*] else ind0=intarr(n_elements(omit)) ; this is a better condition because it is also valid for when the user wants to omit 'spectrum' (non-filter) data points.
+    tagnames = tag_names(data_struct)    
+    if typename(filters) EQ 'LIST' then ind0 = filters[*] else ind0=intarr(n_elements(filters))
     ;because types can be float or double but not long. 
-    
-    for i=0L,n_elements(omit)-1 do begin
-        dim_i = n_elements(omit(i)) ;getting the dimension of each element of the list/array
+    for i=0L,n_elements(filters)-1 do begin
+        dim_i = n_elements(filters(i)) ;getting the dimension of each element of the list/array
         ind0[i] = intarr(dim_i) + la_undef() ;initializing to la_undef()     
-    endfor
-    
+    endfor    
     ;Gathering the indices of the filters to remove.        
-    
-    for i=0L,n_elements(omit)-1 do begin
-        
-        dim_i=n_elements(omit(i)) ;Getting the dimension of each element of the list
-
-        arr_i=intarr(dim_i) + la_undef() ;initializing to la_undef()
-        
+    for i=0L,n_elements(filters)-1 do begin        
+        dim_i=n_elements(filters(i)) ;Getting the dimension of each element of the list
+        arr_i=intarr(dim_i) + la_undef() ;initializing to la_undef()        
         for j=0L,dim_i-1 do begin
-            
             ;testing whether the element corresponds to a specific wavelength. 
-            ;accepts both numbers/strings
-            
-            if valid_num((omit[i])[j]) then begin
-                
-                ind=where(float((omit[i])[j]) EQ data_struct.wave,test0)
-                if test0 ne 0 then arr_i[j] = ind else message, 'WAVELENGTH '+strtrim((omit[i])[j],2)+' does not correspond to any spectrum point in the supplied data strucure.'
-            endif else begin
-                
-                ind = where((omit[i])[j] EQ filters_dustem,test1) ;Test if the filter is in the wrapper's database
-                if test1 eq 0 then message, 'Filter '+strtrim((omit[i])[j],2)+' cannot be found in the DustemWrap database.'
-                
-                ind = where((omit[i])[j] EQ filters_data,test2) ;Test if the filter in in the data itself
-                if test2 ne 0 then arr_i[j] = ind else message, 'Filter '+strtrim((omit[i])[j],2)+' cannot be found in the data supplied.'  
-            
+            ;accepts both numbers/strings          
+            if valid_num((filters[i])[j]) then begin               
+                ind=where(float((filters[i])[j]) EQ data_struct.wave,test0)
+                if test0 ne 0 and data_struct[ind].filter EQ 'SPECTRUM' then arr_i[j] = ind else message, 'WAVELENGTH '+strtrim((filters[i])[j],2)+' does not correspond to any spectrum point in the supplied data strucure.'
+            endif else begin  
+                ind = where((filters[i])[j] EQ filters_dustem,test1) 
+                if test1 eq 0 then message, "Filter "+strtrim((filters[i])[j],2)+" isn't in the DustEMWrap Filters' list"
+                ind = where((filters[i])[j] EQ filters_data,test2) ;Test if the filter in in the data itself
+                if test2 ne 0 then arr_i[j] = ind else message, 'Filter '+strtrim((filters[i])[j],2)+' cannot be found in the supplied data structure.'              
             endelse
-               
-        endfor
-        
+        endfor        
         ind0[i] = arr_i ;Indices of the filters to be removed in the data structure
-    
     endfor
  
+    If typename(ind0) EQ 'LIST' then indices = ind0[i] ELSE indices = ind0 
+     
+     ;If default isn't set, errors in dustem_check_data.pro can occur because of differences in tag values. A common behavior of dustem_check_data.pro
+     ;example: filter removed for StokesI but not for SIGMAII
+    IF keyword_set(default) THEN BEGIN
  
-        eq_tags = ['STOKESI','EXT_I','STOKESQ','STOKESU','LARGEP','SMALLP','PSI','EXT_Q','EXT_U','EXT_P','EXT_smallp','PSI']
-            
-        errvec = ['SIGMAII','SIGEXTI','SIGMAQQ','SIGMAUU','SIGMA_LARGEP','SIGMA_SMALLP','SIGMA_PSI','SIGEXTQ','SIGEXTU','SIGEXTP','SIGEXTsmallp', 'SIGEXT_PSI']
-        
+        ;Part pertainig to the /default keyword
+        ;bunch of tests to locate datasets depending on STOKESI, STOKESQ, STOKESU, LARGEP, SMALLP and PSI     
+        ;is it an emission or extinction structure?
+        ind_m = where(tagnames EQ 'STOKESI', ctm)
+        ind_x = where(tagnames EQ 'EXT_I', ctx)
+        IF ctm NE 0 THEN BEGIN ;no counters are used in the following because it's a consequence of the test being valid.
+            ;Getting the indices this way because it allows for an easy modification if/when tagnames in the xcat emission/extinction file change
+            ind_set_StokesI =  fix([where(strmatch(tagnames,'STOKESI')), $
+                                 where(strmatch(tagnames,'SIGMAII'))]) 
+            ind_set_StokesQ = fix([where(strmatch(tagnames,'STOKESQ')),  $ 
+                                where(strmatch(tagnames,'SIGMAQQ')),     $
+                                where(strmatch(tagnames,'SIGMAIQ')) ])
+            ind_set_StokesU = fix([where(strmatch(tagnames,'STOKESU')),  $ 
+                                where(strmatch(tagnames,'SIGMAUU')),     $
+                                where(strmatch(tagnames,'SIGMAIU')) ])
+            ind_set_LargeP = fix([where(strmatch(tagnames,'LARGEP')),    $
+                                where(strmatch(tagnames,'SIGMA_LARGEP'))])
+            ind_set_smallp = fix([where(strmatch(tagnames,'SMALLP')),    $
+                               where(strmatch(tagnames,'SIGMA_SMALLP'))])
+            ind_set_psi = fix([where(strmatch(tagnames,'PSI')),          $
+                            where(strmatch(tagnames,'SIGMA_PSI'))])                    
+        ENDIF
+        IF ctx NE 0 THEN BEGIN
+            ind_set_EXT_I =  fix([where(strmatch(tagnames,'EXT_I')),          $ 
+                               where(strmatch(tagnames,'SIGEXTII')) ]) 
+            ind_set_EXT_Q = fix([where(strmatch(tagnames,'EXT_Q')),           $
+                              where(strmatch(tagnames,'SIGEXTQQ')),           $
+                              where(strmatch(tagnames,'SIGEXTIQ')) ])  
+            ind_set_EXT_U = fix([where(strmatch(tagnames,'EXT_U')),           $
+                              where(strmatch(tagnames,'SIGEXTUU')),           $
+                              where(strmatch(tagnames,'SIGEXTIU')) ]) 
+            ind_set_EXT_P = fix([where(strmatch(tagnames,'EXT_P')),           $
+                              where(strmatch(tagnames,'SIGEXTP'))])
+            ind_set_EXT_smallp = fix([where(strmatch(tagnames,'EXT_SMALLP')), $
+                                   where(strmatch(tagnames,'SIGEXTSMALLP'))])
+            ind_set_psi = fix([where(strmatch(tagnames,'PSI')),               $
+                            where(strmatch(tagnames,'SIGEXTPSI'))])
+        ENDIF
+    ENDIF
+   
+    ;setting filters' data to la_undef()    
     IF keyword_set(data_set) then begin
-        
-        for i=0L,n_elements(data_set)-1 do begin 
-            ind_set = where(tagnames EQ data_set(i),ctset)
-            ;here using eq_tags and errvec for another purpose
-            ;because I need to locate the associated errors
  
+        FOR i=0L,n_elements(data_set)-1 DO BEGIN
+            ind_set = where(tagnames EQ data_set(i),ctset)
             if ctset ne 0 then begin
-                
-                inderr = where(eq_tags EQ data_set(i)) ;no need for counters this is supposedly true at all times plus the error message is below in the next test
-                ind_errset = where(tagnames EQ errvec[inderr[0]])
-                
-                ;in the case of PSI for emission and for absorption 
-                ;I need to know the different cases: 
-                
-                ;EMISSION
-                
-                if data_set(i) EQ 'PSI' and tagnames[3] EQ 'STOKESI' then ind_errset = where(tagnames EQ errvec[6])   
-                
-                
-                ;EXTINCION
-                
-                if data_set(i) EQ 'PSI' and tagnames[3] EQ 'EXT_I' then ind_errset = where(tagnames EQ errvec[11])
-                
-                ;stop
-            endif else begin
-               ind_set1 = where(tag_names(*!dustem_data) EQ data_set(i),ctset)
-               if ctset eq 0 then message, 'Aborting. The supplied data set is not found in the DustemWrap database.'
-               ind_set = where(tagnames EQ eq_tags(ind_set1[0]))
-               ind_errset = where(tagnames EQ errvec(ind_set1[0]))
-            ;stop
-            endelse
  
-            if typename(ind0) EQ 'LIST' then begin 
-                data_struct(ind0[i]).(ind_set) = la_undef()
-                data_struct(ind0[i]).(ind_errset) = la_undef() 
-            endif else begin
-                data_struct(ind0).(ind_set) = la_undef()
-                data_struct(ind0).(ind_errset) = la_undef()  
-            endelse
-             
-        endfor
-    endif else begin
+                ;the requires the default keyword to be set
+                IF keyword_set(default)  THEN BEGIN    
+                    ;EMISSION CASE
+                    IF ctm NE 0 THEN BEGIN
+                        ;testing data_set(i) against the above strings. 
+                        test_StokesI = where(ind_set_StokesI EQ ind_set, ct_StokesI)
+                        IF ct_StokesI NE 0 THEN data_struct(indices).(ind_set_StokesI) = la_undef()
+                        test_StokesQ =  where(ind_set_StokesQ EQ ind_set, ct_StokesQ)
+                        IF ct_StokesQ NE 0 THEN data_struct(indices).(ind_set_StokesQ) = la_undef()
+                        test_StokesU = where(ind_set_StokesU EQ ind_set, ct_StokesU)
+                        IF ct_StokesU NE 0 THEN data_struct(indices).(ind_set_StokesU) = la_undef()
+                        test_LargeP = where(ind_set_LargeP EQ ind_set, ct_LargeP)
+                        IF ct_LargeP NE 0 THEN data_struct(indices).(ind_set_LargeP) = la_undef()
+                        test_smallp = where(ind_set_smallp EQ ind_set, ct_smallp)
+                        IF ct_smallp NE 0 THEN data_struct(indices).(ind_set_smallp) = la_undef()
+                        test_psi = where(ind_set_psi EQ ind_set, ct_psi)
+                        IF ct_psi NE 0 THEN data_struct(indices).(ind_set_psi) = la_undef()
+                    ENDIF     
+                    ;EXTINCTION CASE
+                    IF ctx NE 0 THEN BEGIN
+                        ;testing data_set(i) against the above strings. 
+                        test_EXT_I = where(ind_set_EXT_I EQ ind_set, ct_EXT_I)
+                        IF ct_EXT_I NE 0 THEN data_struct(indices).(ind_set_EXT_I) = la_undef()
+                        test_EXT_Q =  where(ind_set_EXT_Q EQ ind_set, ct_EXT_Q)
+                        IF ct_EXT_Q NE 0 THEN data_struct(indices).(ind_set_EXT_Q) = la_undef()
+                        test_EXT_U = where(ind_set_EXT_U EQ ind_set, ct_EXT_U)
+                        IF ct_EXT_U NE 0 THEN data_struct(indices).(ind_set_EXT_U) = la_undef()
+                        test_EXT_P = where(ind_set_EXT_P EQ ind_set, ct_EXT_P)
+                        IF ct_EXT_P NE 0 THEN data_struct(indices).(ind_set_EXT_P) = la_undef()
+                        test_EXT_smallp = where(ind_set_EXT_smallp EQ ind_set, ct_EXT_smallp)
+                        IF ct_EXT_smallp NE 0 THEN data_struct(indices).(ind_set_EXT_smallp) = la_undef()
+                        test_psi = where(ind_set_psi EQ ind_set, ct_psi)
+                        IF ct_psi NE 0 THEN data_struct(indices).(ind_set_psi) = la_undef()
+                    ENDIF         
+                ENDIF ELSE data_struct(indices).(ind_set) = la_undef()            
+            ENDIF
+        ENDFOR
+    ENDIF ELSE BEGIN ;If no datasets are supplied, all tag values are set to la_undef()
         ind_tags = where(tagnames ne 'INSTRU' and tagnames ne 'FILTER' and tagnames ne 'WAVE')
-        for j=0L,n_elements(ind_tags)-1 do begin
-            data_struct(ind0).(ind_tags(j)) = la_undef()               
-        endfor 
+        FOR j=0L,n_elements(ind_tags)-1 DO BEGIN
+            data_struct(indices).(ind_tags(j)) = la_undef()               
+        ENDFOR 
     endelse
-
-    
 ENDIF ELSE message, 'Cannot proceed. Keyword(s) missing. Refer to help for keyword options.'
  
-return, data_struct
-
+RETURN, data_struct
 the_end:
  
  
@@ -229,7 +229,7 @@ end
 ;== SET THE OBSERVATIONAL STRUCTURE
 ;== sed is passed twice -- the first occurrence is the SED that you
 ;== wish to fit, the second occurrence is the SED that you wish to visualise. 
-dustem_set_data,sed,sed
+dustem_set_data,m_fit=sed,m_show=sed
  
 ; ;== SET INITIAL VALUES AND LIMITS OF THE PARAMETERS THAT WILL BE
 ; ;== ADJUSTED DURING THE FIT
-PRO dustem_set_data,m_fit,m_show,x_fit,x_show,rchi2_weight=rchi2_weight,f_HI=f_HI,help=help
+PRO dustem_set_data,m_fit=m_fit,m_show=m_show,x_fit=x_fit,x_show=x_show,rchi2_weight=rchi2_weight,f_HI=f_HI,help=help
  
 ;+
 ; NAME:
 ;    dustem_set_data
 ;
 ; PURPOSE:
-;    Initializes the dustem data structure (*!dustem_data) used in the fitting
-;    Initializes the !dustem_show structure which is either a copy or a more detailed version of !dustem_data 
-;
+;    Set the *!dustem data (and *!dustem_show) datasets in emission and/or extinction from input data structures
+;    *!dustem_data is important for the fitting of data and its general handling by DustEMWrap.
 ; CATEGORY:
 ;    DustEMWrap, Mid-Level, Distributed, Initialization
 ;
 ; CALLING SEQUENCE:
-;    dustem_set_data[,m_fit,x_fit][,m_show,x_show][,rchi2_weight=][,f_HI=][,/help]
+;    dustem_set_data,[,m_fit=,x_fit=][,m_show=,x_show=],[,rchi2_weight=][,f_HI=][,/help]
 ;
 ; INPUTS:
 ;    None
 ;
 ; OPTIONAL INPUT PARAMETERS:
-;    m_fit : dustemwrap structure contaning emission data to be fitted 
-;    x_fit : dustemwrap structure containing extinction data to be fitted
-;    m_show : dustemwrap structure containing emission data to be displayed
-;    x_show : dustemwrap structure containing extinctiond data to be displayed
-;    rchi2_weight : dustemwrap structure containing the wieghts for chi2 calculation
+;    m_fit : DustEMWrap structure contaning emission data to be fitted 
+;    m_show : DustEMWrap structure containing emission data to be displayed
+;    x_fit : DusteEMWrap structure containing extinction data to be fitted
+;    x_show : DustEMWrap structure containing extinctiond data to be displayed
+;    rchi2_weight : DustEMWrap structure containing the wieghts for chi2 calculation
 ;    f_HI : multiplicative factor for the SED values (extinction and emission)
 ;
 ; OUTPUTS:
-;    None
+;    None/ALL OF THE ABOVE? 
 ;
 ; OPTIONAL OUTPUT PARAMETERS:
 ;    None
@@ -52,15 +51,14 @@ PRO dustem_set_data,m_fit,m_show,x_fit,x_show,rchi2_weight=rchi2_weight,f_HI=f_H
 ;    dir=!dustem_wrap_soft_dir+'/Data/EXAMPLE_OBSDATA/'
 ;    file=dir+'example_SED_1.xcat'
 ;    spec=read_xcat(file,/silent)
-;    dustem_set_data,spec,x_fit,spec,x_show)
-;    #in this example !dustem_data and !dustem_show are identical
+;    dustem_set_data,m_fit=spec,m_show=spec
+;    nb: in this example *!dustem_data and *!dustem_show end up identical
 ;
 ; MODIFICATION HISTORY:
 ;    Written by J.-Ph. Bernard 2007
 ;    V. Guillet (2012) : dustem_set_data is turned into a function which can be used 
 ;                        indifferently for sed, ext, polext
-;    I. Choubani (2022): dustem_check_data is introduced and the data structure format of the latest release is respected.
-;                       dustem_set_data is turned into a procedure.
+;    I. Choubani (2022): dustem_set_data is turned into a procedure for emission/extinction with/without polarization.
 ;    Evolution details on the DustEMWrap gitlab.
 ;    See http://dustemwrap.irap.omp.eu/ for FAQ and help.  
 ;-
@@ -76,25 +74,18 @@ for i=0L,n_tags(*!dustem_data)-1 do begin
     (*!dustem_show).(i) = ptr_new()
 endfor
  
-;#FITTING STRUCTURE
-
-;To me this is unnecessary... as dustem_check_data is always needed as it shapes the output structures (that would otherwise not exist)
-;in order to prepare them for the mpfit run.
-;the *!dustem_data tags are always cleaned so data will never exist if this keyword is used.
-;commenting the use of nocheck_data for now
-  
-;IF not keyword_set(nocheck_data) THEN BEGIN
-    dustem_check_data,m_fit,x_fit,sed,ext,polext,polsed,polfrac,psi_em,qsed,used,qext,uext,psi_ext,fpolext
-;ENDIF
-
-;outputs whatever the input structure has, into organized seperate structures formatted for the fitting process.
+;Outputs have the format required by !dustem_data and the subsequent fitting process.
+dustem_check_data, m_fit,x_fit,sed=sed,ext=ext,polext=polext, $
+                   polsed=polsed,polfrac=polfrac,psi_em=psi_em, $
+                   qsed=qsed,used=used,qext=qext,uext=uext, $
+                   psi_ext=psi_ext,fpolext=fpolext
  
 ;FITTING STRUCTURE INITIALIZATION
 IF isa(sed) THEN (*!dustem_data).sed = ptr_new(sed)
 IF isa(ext) THEN (*!dustem_data).ext = ptr_new(ext)
  
 ;####################
-;OLD VARIABLE. KEPT IT.
+;RELIC. For Annie to judge if this is necessary
 ; If f_HI is specified, multiply the data by f_HI
 If keyword_set(f_HI) and ptr_valid((*!dustem_data).sed) then begin
     if f_HI gt 0 then (*(*!dustem_data).sed).values *= f_HI else f_HI = 1.
@@ -105,27 +96,33 @@ endif else f_HI = 1.
 defsysv,'!dustem_f_HI',f_HI
 ;####################
  
+;Problem here is that the user can activate !run_pol without wanting to be in polarization mode. 
+;reinitialze !run_pol here?  
+
+If !run_pol THEN BEGIN
+    If tag_exist(*!dustem_show,'QSED') THEN BEGIN
+        IF ~isa((*!dustem_data).qsed) THEN !run_pol=0 
+    ENDIF ELSE !run_pol=0
+ENDIF
+
 if !run_pol then begin
  
     if keyword_set(m_fit) then begin
  
         teststks = isa(qsed) and isa(used)
-    ;stop
         IF ~teststks  then message, 'Stokes parameters are not set correctly. Please check the input structure. Aborting...'
-    
-        ;☆EMISSION 
         message, 'Polarization component(s) to fit: QSED and USED' ,/continue
  
-        
-        ;☆Mandatory presence in polar mode 
         IF isa(qsed) THEN BEGIN        
             (*!dustem_data).qsed = ptr_new(qsed)
+            ;RELIC
             if keyword_set(f_HI) then if f_HI gt 0 then $
           	(*(*!dustem_data).qsed).values *= f_HI
         ENDIF    
-        ;☆Mandatory presence in polar mode
+        
         if isa(used) then BEGIN
             (*!dustem_data).used = ptr_new(used)
+            ;RELIC
             if keyword_set(f_HI) then if f_HI gt 0 then $
           	(*(*!dustem_data).used).values *= f_HI
         ENDIF
@@ -133,6 +130,7 @@ if !run_pol then begin
         if isa(polsed) then BEGIN
  
             (*!dustem_data).polsed = ptr_new(polsed)
+            ;RELIC
             if keyword_set(f_HI) then if f_HI gt 0 then $
           	(*(*!dustem_data).polsed).values *= f_HI
  
@@ -141,6 +139,7 @@ if !run_pol then begin
         if isa(polfrac) then BEGIN
  
             (*!dustem_data).polfrac = ptr_new(polfrac)
+            ;RELIC
             if keyword_set(f_HI) then if f_HI gt 0 then $
           	(*(*!dustem_data).polfrac).values *= f_HI
  
@@ -149,23 +148,22 @@ if !run_pol then begin
         if isa(psi_em) then BEGIN
  
             (*!dustem_data).psi_em = ptr_new(psi_em)
+            ;RELIC
             if keyword_set(f_HI) then if f_HI gt 0 then $
           	(*(*!dustem_data).psi_em).values *= f_HI
  
         ENDIF 
  
-        
     endif
  
     if keyword_set(x_fit) then begin
  
-        ;Two tests that determine what the user will eventually fit
         testexstks = isa(qext) and isa(uext)
  
         IF ~testexstks then message, 'Extinction stokes parameters/Polarization data is not set correctly. Please check the input structure. Aborting...'
  
-        ;EXTINCTION - allowed for the default fitting of both because I do not know if the same formalism should be applied to the extinction data because it also implies deviding extinction data into two components. 
-       
+        ;EXTINCTION - 
+        
         message, 'Extinction polarization component(s) to fit: QEXT and UEXT',/continue
  
         if isa(polext) then BEGIN        
@@ -200,22 +198,22 @@ if !run_pol then begin
     endif
 endif
  
-;#SHOWING STRUCTURE
+;SHOWING STRUCTURE / IT IS NEEDED TO BE ABLE TO LOCATE THE HIDDEN DATA POINTS WHEN COMPARING WITH !dustem_data.
+;when creating the HUGE system variable JP wants to create. We'll be able to omit it from DusteEMWrap for good.
  
 if keyword_set(m_fit) and not keyword_set(m_show) then m_show=m_fit
 if keyword_set(x_fit) and not keyword_set(x_show) then x_show = x_fit
  
-
-;Setting of the structure that will be displayed
-;IF not keyword_set(nocheck_data) THEN BEGIN
-    dustem_check_data,m_show,x_show,sed,ext,polext,polsed,polfrac,psi_em,qsed,used,qext,uext,psi_ext,fpolext
-;ENDIF
+dustem_check_data, m_show,x_show,sed=sed,ext=ext,polext=polext, $
+                   polsed=polsed,polfrac=polfrac,psi_em=psi_em, $
+                   qsed=qsed,used=used,qext=qext,uext=uext, $
+                   psi_ext=psi_ext,fpolext=fpolext
  
 IF isa(sed) THEN (*!dustem_show).sed = ptr_new(sed)
 IF isa(ext) THEN (*!dustem_show).ext = ptr_new(ext)
  
 ;####################
-;OLD VARIABLE. KEPT IT.
+;RELIC
 ; If f_HI is specified, multiply the data by f_HI
 If keyword_set(f_HI) and ptr_valid((*!dustem_show).sed) then begin
     if f_HI gt 0 then (*(*!dustem_show).sed).values *= f_HI else f_HI = 1.
@@ -234,19 +232,6 @@ if !run_pol then begin
  
         IF (~teststks and ~isa(polsed)) or (~teststks and ~isa(polfrac)) then message, 'Stokes parameters/Polarization showing data is not set correctly. Please check the input structure. Aborting...'
  
-        if teststks and isa(polsed) and ~(isa(polfrac)) and ~(isa(psi_em)) then nowshowing = 'QSED, USED and POLSED'
-        if teststks and isa(polsed) and ~(isa(polfrac)) and isa(psi_em) then nowshowing = 'QSED, USED, POLSED and PSI_EM'
-        if teststks and ~(isa(polsed)) and isa(polfrac) and ~(isa(psi_em)) then nowshowing = 'QSED, USED and POLFRAC'
-        if teststks and ~(isa(polsed)) and isa(polfrac) and isa(psi_em) then nowshowing = 'QSED, USED, POLFRAC and PSI_EM'
-        if teststks and ~(isa(polsed)) and ~(isa(polfrac)) and ~(isa(psi_em)) then nowshowing = 'QSED and USED'
-        if teststks and isa(polsed) and isa(polfrac) and ~(isa(psi_em)) then nowshowing = 'QSED, USED, POLSED and POLFRAC'
-        if teststks and isa(polsed) and isa(polfrac) and isa(psi_em) then nowshowing = 'QSED, USED, POLFRAC, POLSED and PSI_EM'
-        if teststks and ~(isa(polsed)) and ~(isa(polfrac)) and isa(psi_em) then nowshowing = 'QSED, USED and PSI_EM'
-        
-
-        message, 'Polarization component(s) to show: '+nowshowing ,/continue
-        
-        
         If isa(polsed) then BEGIN    ;Apply changes to !dustem_data here.      
             (*!dustem_show).polsed = ptr_new(polsed)
             if keyword_set(f_HI) then if f_HI gt 0 then $
@@ -277,19 +262,7 @@ if !run_pol then begin
         teststks = isa(qext) and isa(uext)
  
         IF (~teststks) then message, 'Extinction stokes parameters/Polarization data is not set correctly. Please check the input structure. Aborting...'
-                
-        if teststks and isa(polext) and ~(isa(polextfrac)) and ~(isa(psi_ext)) then nowshowing = 'QEXT, UEXT and POLEXT'
-        if teststks and isa(polext) and ~(isa(polextfrac)) and isa(psi_ext) then nowshowing = 'QEXT, UEXT, POLEXT and PSI_EXT'
-        if teststks and ~(isa(polext)) and isa(polextfrac) and ~(isa(psi_ext)) then nowshowing = 'QEXT, UEXT and POLEXTFRAC'
-        if teststks and ~(isa(polext)) and isa(polextfrac) and isa(psi_ext) then nowshowing = 'QEXT, UEXT, POLEXTFRAC and PSI_EXT'
-        if teststks and ~(isa(polext)) and ~(isa(polextfrac)) and ~(isa(psi_ext)) then nowshowing = 'QEXT and UEXT'
-        if teststks and isa(polext) and isa(polextfrac) and ~(isa(psi_ext)) then nowshowing = 'QEXT, UEXT, POLEXT and POLEXTFRAC'
-        if teststks and isa(polext) and isa(polextfrac) and isa(psi_ext) then nowshowing = 'QEXT, UEXT, POLEXTFRAC, POLEXT and PSI_EXT'
-        if teststks and ~(isa(polext)) and ~(isa(polextfrac)) and isa(psi_ext) then nowshowing = 'QEXT, UEXT and PSI_EXT'
-        
-        
-        message, 'Polarization component(s) to show: '+nowshowing ,/continue
-        
+      
         ;EXTINCTION
         if isa(polext) then BEGIN        
             (*!dustem_show).polext = ptr_new(polext)
@@ -364,10 +337,4 @@ ENDIF
  
 the_end:
  
-; 
-; return,0.
-
-
-
-
 END
@@ -218,7 +218,7 @@ end
 for i=4l,n_tags(sed)-1 do begin
     sed.(i) = sed.sigmaii
 endfor
-dustem_set_data,sed,sed
+dustem_set_data,m_fit=sed,m_show=sed
  
 ;;== SET INITIAL VALUES AND LIMITS OF THE PARAMETERS THAT WILL BE
 ;;== ADJUSTED DURING THE FIT
@@ -154,8 +154,7 @@ if not keyword_set(dustem_ext) and isa((*!dustem_data).ext) then begin
       dustem_ext = dustem_compute_ext(p_dim,st=st,EXT_spec=EXT_spec)
  
       if !run_pol and tag_exist(*!dustem_show,'qext') && !run_lin then begin ;any polarization tag (qsed,used,qext,usext,polfrac) can be used for this test
-
-          ;stop                              
+                              
           dustem_polext = dustem_compute_polext(p_dim,st=st,POLEXT_spec=POLEXT_spec,SPEXT_spec=SPEXT_spec,dustem_fpolext=dustem_fpolext)
           toto = dustem_compute_stokext(p_dim,st=st,QEXT_spec=QEXT_spec,UEXT_spec=UEXT_spec,PSIEXT_spec=PSIEXT_spec,dustem_psi_ext=dustem_psi_ext) 
           dustem_qext = toto[0]
@@ -260,6 +259,14 @@ endif else begin
     rchi2 = la_undef();maybe not the best initialization 
 endelse 
  
+;changing tag_exist() by isa() because the user can mistakenly activate the !run_pol keyword
+
+If !run_pol THEN BEGIN
+    If tag_exist(*!dustem_show,'QSED') THEN BEGIN
+        IF ~isa((*!dustem_data).qsed) THEN !run_pol=0 
+    ENDIF ELSE !run_pol = 0
+ENDIF
+
 ;===========Window positionning parameters
 if !run_pol and tag_exist(*!dustem_show,'qsed') then BEGIN ;qsed tag is sufficient for the test
     wdelta_x=60
@@ -500,7 +507,7 @@ if test_m then begin
  
         dustem_interp = list(dustem_sed) ;DustEmWrap SED predictions . 
         dustem_spec = list(SED_spec) ;DustEM spectra predictions
-        position = list(p_sed,np_sed);list(list(p_sed,np_sed)) ; I think I need this ...
+        position = list(p_sed,np_sed)  ;list(list(p_sed,np_sed)) ; I think I need this ...
         ;position_n =list(np_sed) 
         datasets = ['SED']
         ;replace by one keyword?
@@ -516,7 +523,7 @@ if test_m then begin
  
     endif else begin 
  
-        ; PLOTTING OF DATA THAT IS UNCHAED 
+        ; PLOTTING OF DATA THAT IS UNCHANGED 
         cgwindow,'dustem_plot_dataset', st, dataset=datasets, position=position,positive_only=positiveonly,negative_only=negativeonly, /addcmd, winid=winid_m, _extra=_extra & cmdind_m+=1 
         ; REFRESHING DATA - to plot the refreshed data for the first time.
         cgwindow,'dustem_plot_dataset', st, dustem_interp,dustem_spec,extra_spec=extra_spec,dataset=datasets,positive_only=positiveonly,negative_only=negativeonly, /refresh ,position=position, /addcmd, winid=winid_m, _extra=_extra & cmdind_m+=1