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 ?
Now the recovery of five nulls for 7th sensor failure and SSF originally at positions 19.93[degrees], 34.88[degrees], 45.44[degrees], 62.02[degrees], and 68.94[degrees] is carried out and shown in Figures 10 and 11.
After optimization, the SLL reduces and nulls are steered back to their original positions as shown in Figure 12.
From Figure 14 it is clear that its SLL increases and nulls are damaged and also lose null depth.
Figure 16 shows the corrected pattern with recovered nulls at main beam pointing at [[theta].sub.s] = 110[degrees].
Figures 7 and 8 show the recovery of three nulls originally at angles of [[theta].sub.1] = 18[degrees], [[theta].sub.2] = 31.43[degrees] and [[theta].sub.3] = 40.94[degrees] for single element failure and SEF.
Now the recovery of six nulls for single element failure and SEF originally at positions 18[degrees], 31.43[degrees], 40.94[degrees], 48.83[degrees], 55.85[degrees] and 68.19[degrees] is carried out and shown in Figs.
For single element failure the SLL is increased to -23.95dB, while due to the [w.sub.7] SEF, SLL is increased to -20.55 dB, which is the price to be paid to achieve deeper nulls including the first null.
Figures 15 and 16 show the recovery of three nulls at angles of [[theta].sub.1] = 18[degrees], [[theta].sub.2] = 40.94[degrees] and [[theta].sub.3] = 48.83[degrees] respectively for single element failure and SEF.
Including null values within your data can have an adverse effect when using this data within any mathematical operations.
You can see an example of the problem that null values cause when looking at certain records in this table, the Stock Value field derives its results by using the Price and the QuantityInStock value ['Price]*[QuantityInStock].
To ensure that the Stock Value can always be calculated, you must first ensure that the Price and QuantityInStock fields can never contain a NULL value.
A further example of the effects of null values can be seen below: