<mathematics, graphics> (After B. Delaunay) For a set S of points in the
Euclidean plane, the unique triangulation DT(S) of S such that no point in S is
inside the circumcircle of any triangle in DT(S). DT(S) is the dual of the
voronoi diagram of S.
degrees of freedom « dehose « DEK « Delaunay
triangulation » delayed control-transfer » delay
instruction » delay slot
<SPARC, programming> A technique used on the SPARC to reduce the effect
of pipeline breaks by executing the instruction after a branch instruction (the
"delay instruction" in the "delay slot"). If there is no useful instruction
which can be placed in the delay slot then the "annul bit" on the control
transfer instruction can be set, preventing execution of the delay instruction
(unless the control transfer is conditional and is taken).
Annulled branches are indicated in SPARC assembler language by appending ",A" to
the operation code. For example,
ADD %L2, %L3, #L4
If the delay instruction is also a control transfer instruction then it
gets more complicated. Both control transfer
instructions are executed (but not the following
instruction) and, assuming they are both taken,
control is transferred briefly to the destination of
the first and then immediately to the destination of
dehose « DEK « Delaunay triangulation « delayed
control-transfer » delay instruction » delay
slot » delete
DEK « Delaunay triangulation « delayed
delay instruction » delay slot » delete »
Delaunay triangulation « delayed control-transfer «
delay instruction « delay slot » delete »
delimiter » delint
1. <operating system> (Or "erase") To make a file inaccessible.
Usually this operation only deletes information from the tables the file system
uses to locate named files; the file's contents still exist on disk and can
sometimes be recovered by scanning the whole disk for strings which are known to
have been in the file. Files created subsequently on the same disk are quite
likely to reuse the same blocks and thus overwrite the deleted file's data
2. <character> The control character with ASCII code 127. Usually
entering this character from the keyboard deletes the last character typed from
the input buffer. Sadly there is great confusion between operating systems and
keyboard manufacturers as to whether this function should be assigned to the
delete or backspace key/character.
The choice of code 127 (binary 1111111) is not arbitrary but dates back to the
use of paper tape for input. The delete key rewound the tape by one character
and punched out all seven holes, thus obliterating whatever character was there
before. The tape reading software ignored any delete characters in the input.
delayed control-transfer « delay instruction « delay
delete » delimiter » delint » Delirium
<character> A character or string used to separate, or mark the start and
end of, items of data in, e.g., a database, source code, or text file.
See also: record.
delay instruction « delay slot « delete «
delimiter » delint » Delirium » Delivered Source
/dee-lint/ To modify code to remove problems detected when linting. Confusingly,
this process is also referred to as "linting" code.
delay slot « delete « delimiter « delint »
Delirium » Delivered Source Instruction » Dell
An embedding coordinate language for parallel programming, implemented on
Sequent Symmetry, Cray, BBN Butterfly.
["Parallel Programming with Coordination Structures", S. Lucco et al, 18th POPL,
delete « delimiter « delint « Delirium »
Delivered Source Instruction » Dell Computer
Corporation » Delphi
Delivered Source Instruction
<programming, unit> (DSI) One line of source code (LOC) developed by a
DSI is the primary input to many tools for estimating software cost. The term
"delivered" is generally meant to exclude non-delivered support software such as
test drivers. However, if these are developed with the same care as delivered
software, with their own reviews, test plans, documentation, etc., then they
should be counted. The "source instructions" include all program instructions
created by project personnel and processed into machine code by some combination
of preprocessors, compilers, and assemblers. It excludes comments and unmodified
utility software. It includes job control language, format statements, and data
delimiter « delint « Delirium « Delivered Source
Instruction » Dell Computer Corporation » Delphi
» Delphi Technique
Dell Computer Corporation
<company> One of the biggest US manufacturers of IBM PC compatibles.
"From notebooks to networks", their slogan says.
delint « Delirium « Delivered Source Instruction «
Dell Computer Corporation » Delphi » Delphi
Technique » Delta
1. <company, communications> A US Internet service provider.
2. <language> Borland's Object Oriented Pascal (OOPascal) Rapid
Application Development package for Microsoft Windows. Delphi combines visual,
component-based design with an optimising native code compiler and scalable
Delirium « Delivered Source Instruction « Dell
Computer Corporation « Delphi » Delphi
Technique » Delta » delta
<programming, tool> A group forecasting technique, generally used for
future events such as technological developments, that uses estimates from
experts and feedback summaries of these estimates for additional estimates by
these experts until reasonable consensus occurs. It has been used in various
software cost-estimating activities, including estimation of factors influencing
Delivered Source Instruction « Dell Computer
Corporation « Delphi « Delphi Technique »
Delta » delta » Delta-4
1. An expression-based language developed by J.C. Cleaveland in 1978.
2. A string-processing language with single-character commands from Tandem
3. A language for system specification of simulation execution.
["System Description and the DELTA Language", E. Holback-Hansen et al, DELTA
Proj Rep 4, Norweg Comput Ctr, Feb 1977].
4. A COBOL generating language produced by Delta Software Entwicklung GmbH.
Dell Computer Corporation « Delphi « Delphi
Delta » delta » Delta-4 » delta conversion
1. A quantitative change, especially a small or incremental one (this use is
general in physics and engineering). "I just doubled the speed of my program!"
"What was the delta on program size?" "About 30 percent." (He doubled the speed
of his program, but increased its size by only 30 percent.)
2. [Unix] A diff, especially a diff stored under the set of version-control
tools called SCCS (Source Code Control System) or RCS (Revision Control System).
See change management.
3. A small quantity, but not as small as epsilon. The jargon usage of delta and
epsilon stems from the traditional use of these letters in mathematics for very
small numerical quantities, particularly in "epsilon-delta" proofs in limit
theory (as in the differential calculus). The term delta is often used, once
epsilon has been mentioned, to mean a quantity that is slightly bigger than
epsilon but still very small. "The cost isn't epsilon, but it's delta" means
that the cost isn't totally negligible, but it is nevertheless very small.
Common constructions include "within delta of ---", "within epsilon of ---":
that is, "close to" and "even closer to".
Delphi « Delphi Technique « Delta « delta »
Delta-4 » delta conversion » Delta-Prolog
Definition and Design of an open Dependable Distributed system architecture. An
Esprit project investigating the achievement of dependability in open
distributed systems, including real-time systems.
Delphi Technique « Delta « delta « Delta-4 »
delta conversion » Delta-Prolog » delta reduction
Delta « delta « Delta-4 « delta conversion »
Delta-Prolog » delta reduction » DELTASE
A Prolog extension with AND-parallelism, don't-know nondeterminism and
interprocess communication using synchronous event goals and distributed
["Delta-Prolog: A Distributed Logic Programming Language", L.M. Pereira et al,
Intl Conf 5th Gen Comp Sys, Nov 1984].
delta « Delta-4 « delta conversion « Delta-Prolog
» delta reduction » DELTASE » demand driven
<theory> In lambda-calculus extended with constants, delta reduction
replaces a function applied to the required number of arguments (a redex) by a
result. E.g. plus 2 3 --> 5. In contrast with beta reduction (the only kind of
reduction in the pure lambda-calculus) the result is not formed simply by
textual substitution of arguments into the body of a function. Instead, a delta
redex is matched against the left hand side of all delta rules and is replaced
by the right hand side of the (first) matching rule. There is notionally one
delta rule for each possible combination of function and arguments. Where this
implies an infinite number of rules, the result is usually defined by reference
to some external system such as mathematical addition or the hardware operations
of some computer. For other types, all rules can be given explicitly, for
example Boolean negation:
not True = False
not False = True
Delta-4 « delta conversion « Delta-Prolog « delta
reduction » DELTASE » demand driven » demand
A distributed processing environment concerned with fault-tolerant and
process-control applications from the Esprit Delta-4 project.
delta conversion « Delta-Prolog « delta reduction «
DELTASE » demand driven » demand paged » demand