Tags
A tag is a keyword or label that categorizes your question with other, similar questions.
Questions about vector spaces equipped with a symplectic form, a non-degenerate, skew-symmetric bilinear form.
268 questions
This group is for questions relating to "group extensions", a general means of describing a group in terms of a particular normal subgroup and quotient group.
268 questions
This tag is for questions relating to multiplicative functions which are arise most commonly in the field of number theory.
266 questions
In category theory, a morphism is a structure-preserving map, such as continuous mappings on topological spaces, measurable functions, and linear maps.
266 questions
For questions about line bundles, that is vector bundles of rank $1$, over topological spaces.
266 questions
A classifying space $BG$ of a topological group $G$ is the quotient of a weakly contractible space $EG$ by a free action of $G$. When $G$ is a discrete group $BG$ has homotopy type of $K(G,1)$ and (co)homology groups of $BG$ coincide with group cohomology of $G$.
266 questions
Automorphic forms are a generalization of the idea of periodic functions in Euclidean space to general topological groups.
265 questions
For questions about linear approximations, $f(x) \approx f(a)+f'(a)(x-a)$ for $x$ around $a$.
264 questions
In vector calculus, the curl is a vector operator that describes the infinitesimal rotation of a vector field in three-dimensional Euclidean space.
264 questions
A Moduli space is a space in algebraic geometry whose points are geometric objects or isomorphism classes of these kinds of objects.
263 questions
263 questions
For questions about Coxeter groups, an abstract group that admits a formal description in terms of reflections.
263 questions
For questions on the solving/usage/applications of the Cauchy-Riemann equations. Use this tag alongside the complex analysis tag.
263 questions
Questions about the negative binomial distribution, a discrete probability distribution.
262 questions
For questions about measurability, that is, whether a subset of a general space belongs to the σ-algebra, or about properties of measurable sets. Use this tag with (measure-theory), (real-analysis), (probability-theory) or (geometric-measure-theory).
262 questions
For questions about Hadamard product between two matrices, or it can concern analytic functions.
261 questions
This tag should be used with convex cones defined as usual within the context of Euclidean spaces or topological vector spaces, and their applications within geometry and topology, optimization, combinatorics and any other related area of mathematics using the classic definition of convex cone.
261 questions
The Mellin transform is an integral transform similar to Laplace and Fourier transforms.
260 questions
This tag is for questions relating to subgradient, an iterative method for solving convex minimization problems, used predominantly in Nondifferentiable optimization for functions that are convex but nondifferentiable. The subgradient method is a very simple algorithm for minimizing convex nondifferentiable functions where newton's method and simple linear programming will not work.
259 questions
For questions on provability, the capability of being demonstrated or logically proved.
258 questions
For questions that involve the divisor counting function, also known as $\sigma_0$, $\tau$, or $d$.
258 questions
For problems involving algebraic methods in combinatorics (especially group theory and representation theory) as well as combinatorial methods in abstract algebra.
256 questions
Two $n\times n$ matrices $A,B$ are similar if there exists some non-singular matrix $P$ such that $A=PBP^{-1}$. Do NOT use this tag when referring to similarity between matrices based on distance or another norm. Use this tag when the question involves similarity between matrices, or conjugacy in the General Linear Group of invertible matrices.
255 questions
This tag is for questions relating to "Graded Module", extensively used in homological algebra. It generalizes graded vector spaces. A graded module that is also a graded ring is called a graded algebra. A graded ring could also be viewed as a graded Z-algebra.
255 questions
This tag is for questions relating to "implicit function", a function or relation in which the dependent variable is not isolated on one side of the equation.
254 questions
Use this tag for questions related to approximate integration, which constitutes a broad family of algorithms for calculating the numerical value of a definite integral.
253 questions
For questions about general congruence relations, i.e. equivalence relations on an algebraic structure that are compatible with the structure. Please DO NOT use this for questions about integer modular arithmetic.
248 questions
For questions regarding the structure and properties of compact manifolds.
247 questions
A step function, also known as a simple function, is a finite sum of characteristic functions of bounded intervals. They are often used in real analysis and measure theory to approximate integrable functions.
246 questions
A monad is a functor from a category to itself together with two natural transformations, commonly called μ (the "multiplication") and η (the "unit"), satisfying conditions that make μ monoidal and η an identity for it.
246 questions
For question involving Bochner space, which are generalization $\mathbb L^p$ spaces in the sense that the values of the functions are themselves in function spaces.
246 questions
For questions about homotopy type theory, including the homotopy theoretic interpretation of type theory or univalent type theory, univalence axiom, higher inductive types or related.
245 questions
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 $x_1$ by a random error or is crafted by an adversary.
245 questions
This tag is for questions relating to the functions of random variables which is a function from $Ω$ into a suitable space of functions (where $Ω$ is the sample space of a probability space that has been specified). Technically, there is also a measurability condition on this function.
244 questions
In Mathematics, set theory, a Multivalued function is defined as a left-total relation (that is, every input is associated with at least one output) in which at least one input is associated with multiple (two or more) outputs.
244 questions