System Functions and Variables

Variable Name: DB
Type: database - Pointer to a sequence database
Synopsis: Darwinuses the DB pointer to indicate the sequence database currently in use. Any operation performed will be performed on the database to which DB points.
Examples:
small

> DB := ReadDb('~cbrg/DB/SwissProt');
> ReadDb('Sample/SH2');          # implicitly assigned to DB

Table: The selectors for objects of type database.

1.1 

Table: The selectors for objects of type database.

Entry, i	Returns the offset of the ith entry
FileName	Returns the external filename.1
Pat, i	Returns the offset into the patricia
	array of the ith sequence character.
string	Returns the database as a string.
TotAA	Returns the total number of bases.
TotChars	Returns the total number of characters
	from all fields of the database.
TotEntries	Returns the total number of entries.
type	Returns the type of the database.2

See also: NucDB, PepDB

Variable Name: NucDB
Type: database - Pointer to a nucleotide database
Synopsis: Darwin uses the NucDB pointer to indicate the DNA database currently in use. Any operation performed will be performed on the database to which NucDB has been assigned. The same selectors available for DB are available for NucDB.
Examples:

> NucDB := ReadDb('~cbrg/DB/EMBL');   # load a DNA file

See also: DB, PepDB

Variable Name: PepDB
Type: database - Pointer to an amino acid database
Synopsis: Darwin uses the PepDB pointer to indicate the amino acid database currently in use. Any operation performed will be performed on the database to which PepDB has been assigned. The same selectors available for DB are available for PepDB.
Examples:

> PepDB := ReadDb('~cbrg/DB/SwissProt');

See also: DB, NucDB

Variable Name: Pi
Type: real
Synopsis: Variable to hold the value of $\pi$.
Examples:

> sin(Pi);
> cos(Pi);

Variable Name: DBL_EPSILON
Type: real
Synopsis: This variable represents the machine epsilon (machine accuracy).
Examples:

> DBL_EPSILON;

System Name: EOF
Type: string
Synopsis: Indicates the end of a file.