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pconvert noao.digiphot.ptools



pconvert -- convert an APPHOT/DAOPHOT text database into an STSDAS table


pconvert textfile table fields


The APPHOT/DAOPHOT text database which is to be converted into an APPHOT/DAOPHOT STSDAS table database.
The name of the output STSDAS table database.
fields = "*"
Template defining the fields to be selected from each record. By default all the fields are output. Fields are specified by using the names defined in the APPHOT/DAOPHOT text database by the #N entries. Upper or lower case and minimum match abbreviations are permissible. For those fields which have multiple entries such as magnitiude, an individual value can be referenced by specifying an array index, e.g. MAG[2] or several values can be selected by specifying a range of elements, e.g. MAG[1-4].
expr = yes
The boolean expression, evaluated independently for each record, which serves as a selection criterion. By default all records are selected.
append = no
If append is yes then the converted APPHOT/DAOPHOT text file is appended to an existing output STSDAS table database.


PCONVERT selects a subset of the fields from each record of an APPHOT/DAOPHOT text database and writes these into an STSDAS tabl database. The #K keyword parameters in the text database are stored as header parameters in the STSDAS table while the selected fields are stored in fields (columns) with the names specified by the text database #N keywords, units specified by the #U keywords, and print format specified by the #F keywords.

The output records are selected on the basis of the boolean expression expr whose variables are the field (column) names specified by the #N keywords in the APPHOT/DAOPHOT text database. If after substituting the values associated with a particular record into the field name variables the expression evaluates to yes, that record is included in the output table.

The supported operators and functions are briefly described below. A detailed description of the boolean expression evaluator and its syntax can be found in the manual page for the IMAGES package HEDIT task.

The following logical operators can be used in the boolean expression.

	equal		  ==	not equal		!=
	less than	  <	less than or equal	<=
	greater than	  >	greater than or equal	>=
	or		  ||	and			&&
	negation	  !	pattern match		?=
	concatenation	  //

The pattern match character ?= takes a string expression as its first argument and a pattern as its second argument. The result is yes if the pattern is contained in the string expression. Patterns are strings which may contain pattern matching metacharacters. The metacharacters themselves can be matched by preceeding them with the escape character. The metacharacters are described below.

	beginning of string	^	end of string		$
	one character		?	zero or more characters	*
	white space		#	escape character	\
	ignore case		{	end ignore case		}
	begin character class	[	end character class	]
	not, in char class	^	range, in char class	-

The boolean expression may also include arithmetic operators and functions. The following arithmetic operators and functions are supported.

addition		+		subtraction		-
multiplication		*		division		/
negation		-		exponentiation		**
absolute value		abs(x)		cosine			cos(x)
sine			sin(x)		tangent			tan(x)
arc cosine		acos(x)		arc sine		asin(x)
arc tangent		atan(x)		arc tangent		atan2(x,y)
exponential		exp(x)		square root		sqrt(x)
natural log		log(x)		common log		log10(x)
minimum			min(x,y)	maximum			max(x,y)
convert to integer	int(x)		convert to real		real(x)
nearest integer		nint(x)		modulo			mod(x)

If the append parameter is "yes" then the converted input text database is appended to the specified output table. When appending to a table each of the output fields must already exist in the output table.


1. Convert the text output from the DAOPHOT PHOT task in the file n4147.mag.1 to an STSDAS table, selecting only the fields ID, XCENTER, YCENTER, MAG,and MSKY ncessary for input to the DAOPHOT fitting routines. Put the output in an STSDAS table named n4147.tmag.1.

   pt> pconvert n4147.mag.1 n4147.tmag.1 "ID,XCENTER,YCENTER,MAG,MSKY"

If there were 4 magnitude fields in n4147.mag.1 then there would be 4 columns in the output table with names of MAG[1], MAG[2], MAG[3] and MAG[4]

2. Convert the same file as in example 1. but append the output to n4147.tmag.1 and only select records with YCENTER <= 200.0.

   pt> pconvert n4147.mag.1 n4147.tmag.1 "ID,XCENTER,YCENTER,MAG,MSKY" \
       expr="YCENTER < 200.0" append+

3. Convert all the records in the NSTAR text database n4147.nst.1 to an STSDAS table.

pt> pconvert n4147.nst.1 n4147.tnst.1 "*"



Changes in the values of the #K keyword quantities which are permitted by the APPHOT/DAOPHOT text database format will be lost in the conversion to STSDAS table format which does not permit such changes. For example users who have set up and run PHOT interactively and changed the values of the parameters after writing the first record to the text database will see only the initial values of the #K keywords in the STSDAS table headers after conversion.



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