# Tags

A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.

 Type to find tags:
 chain-rule× 107 For questions involving the chain rule in analysis. ceiling-function× 105 The function that maps a real number $x$ to the smallest integer greater than or equal to $x$ (which is often denoted $\lceil x\rceil$. See also (floor-function). bifurcation× 105 the mathematical study of changes in the qualitative or topological structure of a given family, such as the integral curves of a family of vector fields, and the solutions of a … projective-schemes× 105 prime-twins× 105 For questions on prime twins. regularization× 105 Regularization, in mathematics and statistics and particularly in the fields of machine learning and inverse problems, refers to a process of introducing additional information in order to solve an il… hash-function× 105 For questions about hash functions: functions from a big set to a smaller one such that the same output $f(x_1)=f(x_2)$ for different input $x_1\ne x_2$ is unlikely, especially if $x_2$ differs from $… stationary-processes× 105 For questions about strictly stationary or stationary in the wide sense sequences or processes. Questions about deterministic stationary processes (in the case of discrete dynamical systems) are welco… graded-modules× 103 multiplicative-function× 102 In number theory, a multiplicative function is a function defined on positive integers such that f(ab)=f(a)f(b) for a,b coprime. E.g. Euler's totient function, sum of divisors and number of divisor… universal-property× 102 unit-of-measure× 101 For questions related to conversion of units. sage× 101 For questions concerning Sage. Consider whether your question would be a better fit at [ask Sage](http://ask.sagemath.org/). z-transform× 101 a discrete analogue to the Laplace transform, in that it maps a time domain signal into a representation in complex frequency plane. latin-square× 101 For questions on or pertaining to Latin squares. affine-schemes× 101 The spectrum of a commutative ring with unit is the set of prime ideals endowed with the Zariski topology. One can define a sheaf of rings on this space : to each Zariski-open set is assigned a commut… associativity× 101 the property shared by many binary operations including group operations. For a binary operation$\cdot$, associativity holds if$(x\cdot y)\cdot z = x \cdot(y\cdot z)$. big-numbers× 100 For questions relating to the computation, estimation and properties of extremely large quantities that are not usually used in mainstream mathematics. eulers-constant× 100 For questions related to Euler's constant$\gamma$, which is defined to be the limiting difference between the natural logarithm and the harmonic series. pell-type-equations× 100 Questions on finding integer solutions to bivariate equations of the form$x^2-Dy^2=a$. greens-theorem× 99 for questions about Green's theorem. Green's theorem gives the relationship between a line integral around a simple closed curve$C$and a double integral over the plane region$D$bounded… almost-everywhere× 99 For questions about the concept of "almost everywhere", that is, questions about properties which holds everywhere, except on a set of measure$0$. This is involved in probability theory as well as in… cantor-set× 99 Questions concerning the Cantor set, which consists of those real numbers in [0,1] that remain after repeatedly removing the open middle third of every interval; it contains those numbers which may be… chebyshev-polynomials× 98 In mathematics the Chebyshev polynomials, named after Pafnuty Chebyshev, are a sequence of orthogonal polynomials which are related to de Moivre's formula and which can be defined recursively. algorithmic-game-theory× 98 an area in the intersection of game theory and algorithm design, whose objective is to design algorithms in strategic environments. (Def: http://en.m.wikipedia.org/wiki/Al… poker× 98 a card game with several variants (Draw, Texas Hold'em, ...), the common goal being to collect face value patterns such as "four of a kind", "full house" or "straight" or all of a suit ("flus… schwartz-space× 98 For question about the Schwartz space, a vector space of smooth functions stable under the Fourier transform. semidefinite-programming× 97 for questions regarding semidefinite programming (SDP) which is a subfield of convex optimization concerned with the optimization of a linear objective function (an objective function is a… neural-networks× 97 used for mathematical formulae or questions related to neural networks. meta-math× 97 the term for the theory in which mathematics is formalized (often PA, ZFC or similar theories). Meta-mathematical statements are statements which are evaluated at the level of the meta-… model-categories× 97 categories with three distinguished classes of morphisms: the weak equivalences, the fibrations and the cofibrations. They provide a natural setting for (homotopy-theory) in an ar… cauchy-integral-formula× 97 In mathematics, Cauchy's integral formula, named after Augustin-Louis Cauchy, is a central statement in complex analysis. It expresses the fact that a holomorphic function defined on a disk is complet… collatz× 96 Dynamics of the iterated map$n \to 3n+1$if$n$is odd and$n \to \frac n2 $if$n$is even. Generalizations to$n \to 3n-1 $or$ n \to 5n+1$or even to$n \to pn+q$. Other names are "$3x+1$-proble… borel-cantelli-lemmas× 96 For questions involving the Borel-Cantelli Lemma or the second Borel-Cantelli Lemma. Use this tag along with (probability-theory), (real-analysis) or (measure-theory) hodge-theory× 96 The study of relations between, one the one hand, the topology of a smooth manifold as encoded in the cohomology groups, and on the other, the set of solutions to the Laplace operator on differential … topological-k-theory× 96 a generalized cohomology theory, for which$K_0(X)$is the Grothendieck group of isomorphism classes of vector bundles over topological space$X\$. See also (algebraic-k-theory)…