null

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null

1. Maths
a. quantitatively zero
b. relating to zero
c. (of a set) having no members
d. (of a sequence) having zero as a limit
2. Physics involving measurement in which an instrument has a zero reading, as with a Wheatstone bridge

null

[nəl]
(mathematics)
Indicating that an object is nonexistent or a quantity is zero.
(navigation)
The azimuth or elevation reading on a navigational device indicated by minimum signal output.
Any of the nodal points on the radiation patterns of some antennas.

null

(programming)
A special value used in several languages to represent the thing referred to by an uninitialised pointer.

<database> A special value that may be stored in some database columns to represent an unknown, missing, not applicable, or undefined value. Nulls are treated completely differently from ordinary values when evaluating SQL expressions and there are several SQL constructs for dealing with nulls.

null

A character that is all 0 bits. Also written as "NUL," it is the first character in the ASCII and EBCDIC data codes. In hex, it displays and prints as 00; in decimal, it may appear as a single zero in a chart of codes, but displays and prints as a blank space.

Nulls are naturally found in binary numbers when a byte contains all zeros, and they are used to pad fields (see padding). A null may function as a delimiter; for example, in C/C++, a null character is inserted at the end of a character string to mark the end of the text.


The Null Is the First
Note the first character at the top of this chart of ASCII characters. The 00 means 0000-0000 bits.
References in periodicals archive ?
Finally, we will discuss the challenge with null values when trying to create totals on a report.
When a value isn't entered into a field, it's a null value.
Though, we have achieved better null depth level due to SEF, but the sidelobe levels and positioning of nulls is still an issue to be taken into account, for which we shall use the nature inspired evolutionary computing technique, i.
The second term in (8) is used for jammer suppression and placement of nulls at their original positions after element failure.
The array factor in this case represents a -30 dB constant SLL with the nulls at specific angles.
If you are entering the data for this record and fail to ask the client for the County name they live in the data will then be considered missing and the record will be shown including a null.
You may also have a case for a null value if you are working in a database and none of its values has a record.
You could use a Null value in this field although it is recommended to use a true value such as "N/A" or "Not Applicable", making information clearer to the user.
Specifying a column as not permitting null values can help maintain data integrity by ensuring that a column in a row always contains data.
The genetic algorithm quickly placed nulls in the array antenna pattern without resorting to a receiver at each array element.
In this application, the phase shifter settings evolve until the antenna pattern has a null in the direction of the jammer.
The null at 45 [degrees] is -56 dB and approximately 31 dB below the quiescent pattern.