Act of performing an initial computation before run time
Part of a 20th-century precomputed mathematical table of common logarithms.
In algorithms, precomputation is the act of performing an initial computation before run time to generate a lookup table that can be used by an algorithm to avoid repeated computation each time it is executed. Precomputation is often used in algorithms that depend on the results of expensive computations that don't depend on the input of the algorithm. A trivial example of precomputation is the use of hardcoded mathematical constants, such as π and e, rather than computing their approximations to the necessary precision at run time.
In databases, the term materialization is used to refer to storing the results of a precomputation,[1][2] such as in a materialized view.[3][4]
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In algorithms, precomputation is the act of performing an initial computation before run time to generate a lookup table that can be used by an algorithm...
random and stored with the password hash. A large salt value prevents precomputation attacks, including rainbow tables, by ensuring that each user's password...
languages, and it is sometimes described as a form of precomputation. As with other forms of precomputation, database users typically use materialized views...
authors of the Logjam attack estimate that the much more difficult precomputation needed to solve the discrete log problem for a 1024-bit prime would...
the hash dictionary to be recomputed for each password sought, making precomputation infeasible, provided that the number of possible salt values is large...
17, 2, 2, 20, 20, 8, 22, 8, 71, 26, 26, 80, 242 }. This requires 2k precomputation and storage to speed up the resulting calculation by a factor of k,...
in hardware for Twofish. An example of such a tradeoff would be the precomputation of round subkeys or s-boxes, which can lead to speed increases of a...
it was shown that the full product is unnecessary if we can perform precomputation on one of the operands. We call a function [ ] : R → Z {\displaystyle...
division, assuming that 1/3a is precomputed, so three iterations plus the precomputation require seven multiplications, three additions, and three divisions...
{\displaystyle S} against any triangle in L ( T ) {\displaystyle L(T)} . As a precomputation, we can take each physical body (represented by a set of triangles)...
intersection of a ray and a triangle in three dimensions without needing precomputation of the plane equation of the plane containing the triangle. Ray-Polygon...
applications that require it. Depending on the values being precomputed, precomputation with interpolation can also be used to shrink the lookup table size...
June 2012). "Non-uniform cracks in the concrete: the power of free precomputation" (PDF). Advances in Cryptology - ASIACRYPT 2013. Lecture Notes in Computer...
1997, and issued April 6, 1999. Olsen, John H., Motion Control with Precomputation Archived 2014-02-28 at the Wayback Machine, filed October 7, 1993, and...
\alpha _{P}\deg(P)}. The Function Field Sieve algorithm consists of a precomputation where the discrete logarithms of irreducible polynomials of small degree...
eigenvector precomputation". In IEEE Conf. CVPR, pp. 1–8, 2008 S. Andrews, G. Hamarneh, A. Saad. Fast random walker with priors using precomputation for interactive...
xn when the base is fixed and the exponent varies. As one can see, precomputations play a key role in these algorithms. Yao's method is orthogonal to...
MIFARE Classic, has instant running time, and does not require a costly precomputation. The new attack allows recovering the secret key of any sector of the...
doubling and 2 w − 2 − 1 {\displaystyle 2^{w-2}-1} point additions for precomputation. The algorithm then requires n {\displaystyle n} point doublings and...
1986, Wu et al. improved dramatically on the running time by avoiding precomputation of the all-pairs shortest paths. Instead, they take a similar approach...
in movie animations Radiosity Finite element method, very good for precomputations. Improved versions are instant radiosity and bidirectional instant...
primes in Diffie–Hellman implementations, and that NSA having done precomputation against those primes in order to break encryption using them in real...
{\displaystyle {\text{GF}}\left(2^{128}\right)} for AES). With some precomputation, only a single multiplication per sector is required (note that addition...
only place where a direct reduction modulo N is necessary is in the precomputation of R2 mod N. Most cryptographic applications require numbers that are...
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