null


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Related to null: null space

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 ?
One implication of this equation is that, unless [N.sub.0] is relatively small, erroneously rejecting at least one of the true null hypotheses is nearly certain: for example, if [alpha] = 0.05 and [N.sub.0] = 100 this probability is 0.994.
Also, in this way we get a foliation of [bar.M] (in the vicinity of [H.sub.u]) by a family ([H.sub.u]) so that [l.sub.u] is in the part of [bar.M] foliated by this family (for details see Carter [13]) such that at each point in this region [l.sub.u] is a null normal to [H.sub.u] for some value of the parameter u.
Null's book offers ample referencing; however, to make the book more readable for the public, he does not footnote his references.
Ball-park null allele frequencies were estimated from the number of apparent null allele carrying 'parents' and the total number of (non-excluded) parents in the database after correcting for ascertainment bias.
You should have zeros on the report where the nulls were previously, and the calculations should work.
As we had assumed the failure of [w.sub.9] element, we lost the null depth as given in Fig.
The decision rules define the strength and type of evidence used to reject or fail to reject the null hypothesis.
"The proponents of reversing the null hypothesis should be extremely careful what they wish for," concludes Curry.
Let [phi] = [phi](s) be null curve in the space [E.sup.3.sub.1].
Finally, Chinese has an as yet unexplained expletive null subject, as in Example (2): (3)