Qualifying fields is adding one ore more constraints on some of the columns. The qualification syntax follows the ASU protocol:
Some typical examples:
||keep only non-blank (i.e. specified, or not-null) values: || != || ||restrict a number to the range 12.0 to 12.5: || 12.0 .. 12.5 || ||restrict a date to before June 1, 2000: || < 2000.06.01 || ||restrict a stellar spectral type ((char) column) to early types: || =*[OBA]* ||
Numeric fieldsThe following table describes all operators available on numeric fields (i.e. not flagged by (char)):
Operator | Meaning | Example |
---|---|---|
= | Strict equality (default) | =10 |
!= | Inequality | !=10 |
>= | Greater or equal | >=10 |
> | Strictly greater | >10 |
<= | Smaller or equal | <=10 |
< | Strictly smaller | <10 |
.. | Range of numbers | 5..10 |
+/- | Range defined by its mean and semi-amplitude (*) | 8+/-2 |
& | AND (logical operator) | 1..5 & 7..9 |
| | OR (logical operator) | 1..5 | 7..9 |
, | List of values | 0,1,2 |
<<; |
List of values. Each value results in a separated table, in a way similar to the output from a list of targets. (**) |
<<;1;2;3 |
! | NOT (logical operator) | ! 1..5 |
Values in Numeric fieldsWhat follows the comparison operators are generally numbers; in a few cases, several ways of writing values are possible:
Type | Meaning | Example |
---|---|---|
null | Unspecified (blank)value | (<0)|null |
now | Current date and time (DATE only) | < now |
RA | Sexagesimal hours, minutes, seconds of time | 23 56 .. 00 04 |
Right ascension in decimal degrees | 359 .. 001 | |
DE | Sexagesimal degrees, minutes, seconds of arc | +41 45 .. +42 30 |
Declination in decimal degrees | +41.75 .. +42.50 | |
DATE/TIME | UT Date and time, alphabetic month | >= 1-Jan-1996 |
UT Date and Time, numeric month | >= 1996.01.01 00:00:00 | |
Julian Date | >=JD2450083.5 |
Character fieldsThe following table describes all operators available on character fields (i.e. flagged by (char)):
Note: to search for non empty fields: |
|
Operator | Meaning | Example |
---|---|---|
~ | Caseless pattern matching (default) | ~ngc*3532* |
= | Pattern matching | =NGC*3532* |
=~ | Caseless equality | =~ngc |
== | Strict equality | ==NGC |
~| | |-separated list of caseless pattern matchings | ~|O*pec|WR* |
=, | comma-separated list of alternatives | =,HST,IRAS |
=| | |-separated list of alternatives | =|HST|IRAS |
!=, | exclusion of a comma-separated list of alternatives | !=,HST,IRAS |
!~ | NOT caseless pattern matching | !~[obafgkm]* |
! | NOT pattern matching | ![OBAFGKM]* |
!= | Strict inequality | !=NGC |
>= | Alphabetically greater or equal | >=A |
> | Alphabetically strictly greater | >M 51 |
<= | Alphabetically smaller or equal | <=B* |
< | Alphabetically strictly smaller | < NGC |
<<; | List of values separated by ;(*) | <<;val1;val2;val3 |
Pattern matching symbolsWhat follows the pattern matching operators (~ = !~ !) is a pattern string which contains the following symbols:
Symbol | Meaning | Example |
---|---|---|
[...] | One of the characters defined within the brackets | =[OBA]* |
The - (dash or minus) indicates a range of characters | =[A-Za-z]* | |
[^...] | Any single character NOT contained within the brackets | =[^OBAFGMN]* |
* | Replaces 0 to n characters | [OB]* |
? | Replaces 1 character | A?C* |
Note about Heading Blanks: when no operator is listed, the leading blanks (blanks at the left of a character column) are ignored.
last update: 13 Feb 2024