In computer science, an array data structure or simply an array is a data structure consisting of a collection of elements ( values or variables ), each identified by at least one array index or key.

Usually programming languages allowing n-based indexing also allow negative index values and other scalar data types like enumerations, or characters may be used as an array index.

In standard arrays, each index is restricted to a certain range of consecutive integers ( or consecutive values of some enumerated type ), and the address of an element is computed by a " linear " formula on the indices.

The size of each element, and the minimum and maximum values allowed for each index may also be included in the dope vector.

In physics and optics, the Abbe number, also known as the V-number or constringence of a transparent material, is a measure of the material's dispersion ( variation of refractive index with wavelength ) in relation to the refractive index, with high values of V indicating low dispersion ( low chromatic aberration ).

The simplest form of index is a sorted list of values that can be searched using a binary search with an adjacent reference to the location of the entry, analogous to the index in the back of a book.

The simplest form of index is a sorted list of values that can be searched using a binary search with an adjacent reference to the location of the entry, analogous to the index in the back of a book.

Elements inside embedded sequences are referenced by additional bracked index values, thus X refers to the second element contained in the sequence that is the third element of X.

For particular values of the modulation index, the carrier amplitude becomes zero and all the signal power is in the sidebands.

The ratio of these two values is the polydispersity index, commonly used to express the " width " of the molecular weight distribution.

Thus studies of different populations using the same contraceptive will yield different values for the index.

In each iteration, the PRGA increments i, looks up the ith element of S, S, and adds that to j, exchanges the values of S and S, and then uses the sum S + S ( modulo 256 ) as an index to fetch a third element of S, ( the keystream value K below ) which is XORed with the next byte of the message to produce the next byte of either ciphertext or plaintext.

; Loop reversal: Loop reversal reverses the order in which values are assigned to the index variable.

Only the index of the codeword in the codebook is sent instead of the quantized values.

The result is an 8 × 8 transform coefficient array in which the element ( top-left ) is the DC ( zero-frequency ) component and entries with increasing vertical and horizontal index values represent higher vertical and horizontal spatial frequencies.

This comparison of the relative values results in an " index value " for each question.

Thomas also presents a simple equation for deriving an index of persistence, which weights not only the number of stems ( ' roots ' ) per meaning, but their relative frequency.

But the quest for such an index goes on ceaselessly, with all manner of investors and speculators participating, ranging from the sedate institutional type virtually to the proverbial shoe-string operator, all seeking doggedly, studiously, daily -- and often nightly -- for the enchanting index that will foretell the eternal secret: Which way will the market move -- up or down??

Just as heavily invested are the endeavors of multitudes of modern men who carry on the quest for the enchanting index.

The markets are far too subtle, and the last word in these endeavors will doubtless never be written, for the enchanting index is about as nebulous as the fountain of youth.

This table originally indicates that index words 1 through 96 and electronic switches 1 through 30 are available for assignment to symbolic references ; ;

At the end of this pass, the table indicates which index words and electronic switches are not available for assignment to symbolic references.

The initial setting of the availability table indicated that the index word or electronic switch was not available for assignment.

During the assignment pass, each instruction is examined for reference to the symbolic name of an index word or electronic switch.

When such a reference is found, an actual address is assigned and the availability table is changed so that the assigned index word or switch is no longer available for later assignment.

It will not, however, be used for symbolic assignment until all other index words or electronic switches have been assigned for the first time.

If, at any time during the assignment pass, the compiler finds that there are no more index words available for assignment, the warning message `` No More Index Words Available '' will be placed in the object program listing, the table will be altered to show that index words 1 through 96 are available, and the assignment will continue as before.

As noted in Appendix C, index words 97 through 99 are never available for assignment to symbolic names by the compiler ; ;

also, index words 93 through 96 may have been made unavailable for assignment.

The first item in the operand, IOCSIXF, is used to specify the first IOCS index word for programs using tape files.

The second item in the operand, IOCSIXG, is used to specify the second IOCS index word for programs using tape files.

The Barker index is published for the Barker Index Committee by W. Heffer & Sons, Ltd., 4 Petty Cury, Cambridge, England.

As the index of refraction of photosensitive surfaces of the SbCs-type lies around 2, the Fresnel losses at the fiber-photocathode interface are about 0.5 percent and the Af factor for the interstage coupler is 0.95.

The Government reported last week that the index of prices received by farmers rose in the month ended at mid-September for the third consecutive month, reaching 242% of the 1910-14 average compared with 237% at mid-July.

being the specific heat for constant volume, is the adiabatic index, and is the number of degrees of freedom ( 3 for monatomic gas, 5 for diatomic gas ).

Under the sponsorship of the Office of Naval Research and the Advanced Research Projects Agency, a data center was established to gather and index all published information on atomic transition probabilities.

There will be a comprehensive index in Volume 3, covering all three volumes.

To enable students and the public to spot Sloan forgeries, the Delaware Art Center ( according to its director, Bruce St. John ) will maintain a complete file of photographs of all Sloan works, as well as a card index file.

If the minimum legal value for every index is 0, then B is the address of the element whose indices are all zero.

With the 9 main keys, ( operated by the index, middle, and ring fingers ), 2 prefix keys and one delete key, the EkaPad can produce all the inputs of a standard qwerty keyboard with one, two, and a few three finger chords.

The most popular and official is search. cpan. org, which includes textual search, a browsable index of modules, and extracted copies of all distributions currently on the CPAN.

Most soft sectored and all hard sectored drives would have also required an extra cut-out for the index hole — a harder modification.

If S is an arbitrary set, then the set S < sup > N </ sup > of all sequences in S becomes a complete metric space if we define the distance between the sequences ( x < sub > n </ sub >) and ( y < sub > n </ sub >) to be, where N is the smallest index for which x < sub > N </ sub > is distinct from y < sub > N </ sub >, or 0 if there is no such index.

A general index of all articles was included for the first time in the 7th edition, a practice maintained until 1974.

Stith Thompson made a major attempt to index the motifs of both folklore and mythology, providing an outline into which new motifs can be placed, and scholars can keep track of all older motifs.

When storing records in a large unsorted file, one may use a hash function to map each record to an index into a table T, and collect in each bucket T a list of the numbers of all records with the same hash value i. Once the table is complete, any two duplicate records will end up in the same bucket.

( sift down the node at index start to the proper place such that all nodes below

A few new instructions were introduced with the 80186 ( referred to as the 8086-2 instruction set in some datasheets ): enter / leave ( replacing several instructions when handling stack frames ), pusha / popa ( push / pop all general registers ), bound ( check array index against bounds ), and ins / outs ( input / output of string ).

* Diversity index – a quantitative measure that increases when the number of types into which a set of entities has been classified increases, and obtains its maximum value for a given number of types when all types are represented by the same number of entities

Another way to reduce the overhead is to eliminate all checking of the loop index.

For example, a non-identity finite group is simple if and only if it is isomorphic to all of its non-identity homomorphic images, a finite group is perfect if and only if it has no normal subgroups of prime index, and a group is imperfect if and only if the derived subgroup is not supplemented by any proper normal subgroup.

, where the intersection runs through all normal subgroups of finite index ).

Perhaps the most commonly used index of reliability is Cronbach's α, which is equivalent to the mean of all possible split-half coefficients.