Boolean


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boolean

[′bü·lē·ən]
(computer science)
A scalar declaration in ALGOL defining variables similar to FORTRAN's logical variables.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

Boolean

(mathematics, logic)
1. Boolean algebra.

<programming> 2. (bool) The type of an expression with two possible values, "true" and "false". Also, a variable of Boolean type or a function with Boolean arguments or result. The most common Boolean functions are AND, OR and NOT.
This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)

Boolean logic

The "mathematics of logic," developed by English mathematician George Boole in the mid-19th century. Just as add, subtract, multiply and divide are the primary operations of arithmetic, AND, OR and NOT are the primary logical operators of Boolean logic and building blocks of every digital circuit. NAND (not AND), NOR (not OR) and XOR (exclusive OR) are variations of AND, OR and NOT (see NAND, NOR and XOR). See Boolean search, binary, logic gate and Bebop to the Boolean Boogie.


Decimal vs. Binary
Decimal arithmetic holds 10 values (0 to 9) in each digit position. In binary, there are only two (0 and 1). Note below the four possible result and carry bits when adding two binary digits (bits) together.


AND, OR and NOT Gates
Transistors wired in series and parallel patterns make up these "gates," which accept inputs of 0 (no pulse) or 1 (a pulse) and generate outputs of 0 or 1. While AND requires that both inputs are 1 to generate an output of 1, OR only needs one input to be 1. NOT reverses the input. For a diagram of these actions, see Boolean gates.



Decimal vs. Binary
Decimal arithmetic holds 10 values (0 to 9) in each digit position. In binary, there are only two (0 and 1). Note below the four possible result and carry bits when adding two binary digits (bits) together.







Add a One and Zero
Trace the red 1 (pulse, current) and white 0 (no pulse, no current) through the gates and notice their outputs. This half-adder circuit is in every CPU.


Add a One and Zero
Trace the red 1 (pulse, current) and white 0 (no pulse, no current) through the gates and notice their outputs. This half-adder circuit is in every CPU.







Trace the Flow Yourself
Choose any two binary digits as input and trace them through this half-adder circuit (0 is no current; 1 is current). Watch how the output is generated.


Trace the Flow Yourself
Choose any two binary digits as input and trace them through this half-adder circuit (0 is no current; 1 is current). Watch how the output is generated.







Patterns of Boolean Logic
Transistors (depicted here as mechanical switches) make up gates. Gates make up circuits, and circuits make up every digital device. There are millions and billions of transistors in modern chips, and they fit in an area smaller than a postage stamp. For more details, see Boolean gates. See transistor and chip.
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References in periodicals archive ?
Libraries could instead save millions of dollars by discontinuing subscriptions to these databases, and focus on teaching researchers how to effectively search Google Scholar or how to use Siri to find biographic information for your researcher paper instead of how to develop an advanced search strategy using Boolean logic to find literature in a database that is complex and difficult to use.
The Boolean model can be directly used for berry number estimation, but the ROI must be defined so that the concentration of particles is similar on it.
Whenever the shape of burnt grain is needed, the shape can be easily obtained by applying a Boolean operation, that is, subtracting the produced flame domain from the unburnt grain (see Figure 3).
Section 3 provides the basic concepts of interpolative Boolean algebra.
In 1988, Xiao and Massey introduced (by using properties of Walsh spectra) the notion of correlation immunity as an important cryptographic measure of a Boolean function with respect to its resistance against the correlation attack (which can be seen as solving a system of multivariate linear equations) [7].
Generally speaking, Boolean dynamic modeling of regulatory network follows three steps: (1) reconstructing the network; (2) identifying Boolean functions from the network topological structure; (3) analyzing the dynamics of the system with or without node perturbations.
To solve the problem, we propose a solution to perform secure boolean adjacent vertex search over encrypted graph data in cloud computing (BASG).
This tip is particularly important when a phrase includes one of the and, or, not Boolean connectors.
Second major characteristic is, by default PubMed adds Boolean operators into user queries and uses automatic term mapping (ATM).
The way we use Boolean values in our error check sheet is to store the test results.