# 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:
 normed-spaces× 710 A vector space $E$, generally over the field $\mathbb R$ or $\mathbb C$ with a map $\lVert \cdot\rVert\colon E\to \mathbb R_+$ satisfying some conditions. numerical-linear-algebra× 688 Questions on the various algorithms used in linear algebra computations (matrix computations). conic-sections× 687 Questions on conic sections and their properties; the curves formed by the intersection of a plane and a cone. Circles, ellipses, hyperbolas, and parabolas are examples of conic sections. analytic-number-theory× 685 Questions on the use of the methods of real/complex analysis in the study of number theory. boolean-algebra× 685 structures which behave similar to a power set with complement, intersection and union. Questions regarding Boolean algebras as structures, or regarding functions defined from/to … tensor-products× 685 Tensor products allow us to build "linear" objects from "multilinear" ones. It can refer to: basic ones from linear algebra/module theory, or more sophisticated versions from differential/algebraic ge… conditional-probability× 679 the probability that an event occurs given something else has already occurred. game-theory× 677 The study of competitive and non-competitive games, equilibrium concepts such as Nash equilibrium, and related subjects. Combinatorial games such as Nim are under (combinatorial-game-theory), and algo… mathematical-physics× 663 "Mathematical physics consists of the application of mathematics to problems in physics and the development of mathematical methods suitable for such applications and for the formulation of physical t… propositional-calculus× 653 Questions about truth tables, conjunctive and disjunctive normal forms, negation, and implication of unquantified propositions would fit very nicely under this tag. Questions about other kind of logic… inner-product-space× 638 a vector space equipped with an inner product. The inner product is a generalisation of the "dot" product often used in vector calculus. big-list× 637 Questions asking for a "big list" of examples, illustrations, etc. Please do not ask too many of these. Please do not use this as the only tag for a question. computability× 635 Questions about Turing computability and recursion theory, including the halting problem and other unsolvable problems. Questions about the resources required to solving particular problems should be … combinations× 630 subsets of a given size of a given finite set. All questions for this tag have to directly involve combinations; if instead the question is about binomial coefficients, use that tag. factoring× 628 For questions about finding factors of e.g. integers or polynomials systems-of-equations× 627 indicates that several equations (of some type) must all hold. Do not use alone! Use in conjunction with (linear-algebra), (polynomials), (pde), (differential-equations), (inequalities) or an… lp-spaces× 625 For questions about $L^p$ spaces, that is, given a measure space $(X,\mathcal F,\mu)$, the vector space of equivalence class of measurable functions with $p$-th power of the absolute value integrable.… distribution-theory× 618 for questions about Schwartz distributions, also known as Generalised Functions. For questions about "probability distributions", use (probability-distributions). For questions about dist… 3d× 617 is for things related to 3-dimensions. For geometry of 3-dimensional solids, please use instead (solid-geometry). For geometry that is not on a plane, but otherwise agnostic of dimensions… partial-derivative× 616 For questions regarding partial derivatives. The partial derivative of a function of several variables is the derivative of the function with respect to one of those variables, with all others held co… homotopy-theory× 613 homotopic, if one of them can by continuously deformed to another. This gives rise to an equivalence relation. A group called homotopy group can be obtained from the equivalence clas… axiom-of-choice× 605 a common set-theoretic axiom with many equivalents and consequences. This tag is for questions on where we use it in certain proofs, and how things would work without the assump… coordinate-systems× 598 Questions on coordinate systems, a geometric method where a point in n-dimensions is assigned a corresponding n-tuple of numbers. factorial× 587 Questions on the factorial function, $n!=n\times(n-1)\times\cdots\times1$. Consider using the tag (gamma-function) if dealing with noninteger arguments. brownian-motion× 582 Questions related to Brownian motion, a continuous stochastic process denoted by $W_t$, $t\geq 0$, with independent increments, such that $W(t)-W(s)$ is normally distributed, with $0$ mean and varianc… contour-integration× 576 Questions on the evaluation of integrals along a locus in the complex plane. elliptic-curves× 576 For questions regarding elliptic curves. Questions on ellipses should be tagged [conic-sections] instead. random× 571 Questions relating to (pseudo)randomness, random oracles, and stochastic processes. operator-algebras× 568 primarily C*-algebras and von Neumann algebras, and associated topics. It also includes more general algebras of operators on Hilbert space, and may include algebr… regression× 549 Questions on (linear or nonlinear) regression, the fitting of functions that best approximate empirical data. vectors× 545 rotations× 541 for questions about *rotations*: a type of rigid motion in a space. infinity× 537 Somewhere beyond the numbers lies the concept of Infinity. But what exactly does "infinity" mean? What rules does it obey? What interesting properties does it have? expectation× 534 For questions about the expectation of a random variable: computations, upper/below bounds, etc... algebraic-curves× 529 an algebraic variety of dimension one. An affine algebraic curve can be described as the zero-locus of $n-1$ independent polynomials of $n$ variables in affine $n$-space over a f… calculus-of-variations× 516 Questions on the calculus of variations, a subfield of calculus that deals with the optimization of functionals.