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Gaia Alerts
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URL:
http://gsaweb.ast.cam.ac.uk/alerts/tools

Save file as "alerts.csv". As of December 9, 2020 there were 14,555 entries.

We will use this as an exercise to demonstrate the "csvkit" family of
programs.

$ csvcut -n alerts.csv
  1: #Name
  2:  Date
  3:  RaDeg
  4:  DecDeg
  5:  AlertMag
  6:  HistoricMag
  7:  HistoricStdDev
  8:  Class
  9:  Published
 10:  Comment
 11:  TNSid

$ sed 1d alerts.csv| csvcut -c8 | sort | uniq -c | sort -k1nr | awk '{a=$1;$1="";printf "%-12s\t%d\n",$0,a}'
 unknown    	10641
 SN Ia      	1432
 QSO        	667    <-
 CV         	481
 SN II      	446
 YSO        	142
 SN IIn     	90
 SN IIP     	86
 AGN        	83
 BL Lac     	55
 SN Ic      	49
 Varstar    	46
 ULENS      	40
 SN Ib      	35
 Nova       	30
 SN IIb     	30
 SLSN       	28
 SN Ib/c    	20
 star       	19
 SN Ic-BL   	17
 SN Ia-pec  	13
 RCrB       	11
 SN I       	10
 TDE        	10   <-
 dM         	10
 XRB        	9
 SN         	8
 SN Ibn     	8
 symbiotic star	7
 CCSN       	4
 SN Ia-CSM  	4
 galaxy     	4
 SN IIL     	3
 SN Iax     	3
 LBV        	2
 Other      	2
 SSO        	2
 ""         	1
 ILRT       	1
 SN I-pec   	1
 SN II?     	1
 SN Ic-pec  	1
 SN imposter	1
 dK         	1