Calculus
The 24 definitions of the calculus library, each with its Epsil spelling, its MathJSON name, its signature and its full description.
Each definition is listed under its Epsil spelling (the MathJSON name when it has none), with its signature in the engine's type syntax. The Standard Library page is the one-page index of every category.
Definitions
bigO
MathJSON BigO · (value) -> number
Landau big-O remainder term. Inert; any numeric approximation (.N()) of an expression containing it is NaN.
circleContour
MathJSON CircleContour · (center: complex, radius: real, orientation: integer?) -> expression
Closed circle: center, positive radius, optional orientation (+1 or -1).
circularIntegrate
MathJSON CircularIntegrate · (function, limits+) -> number
Closed-path integral. Evaluates supported explicit contours by the residue theorem.
contourIntegrate
MathJSON ContourIntegrate · (expression, variable: symbol, contour: expression) -> number
Symbolic integral over an explicit closed contour, using the residue theorem.
D
(expression, variables: symbol*) -> expression
Symbolic partial derivative with respect to one or more variables.
dSolve
MathJSON DSolve · (expression, symbol, symbol) -> expression
Symbolic differential equation solver.
derivative
MathJSON Derivative · (function, order: number*) -> function
Derivative operator that returns a derivative function.
integrate
MathJSON Integrate · (function, limits+) -> list<number> | list<tuple> | number | tuple
Symbolic integral with optional bounds.
interpolatingFunction
MathJSON InterpolatingFunction · (list<any>, number?) -> number
Piecewise-quartic dense-output interpolant of a numeric ODE solution (produced by NDSolveFunction). The first operand is the per-step coefficient table; applied to a number, it evaluates the solution there (clamping to the covered interval outside it). Stays symbolic for a non-numeric argument.
jacobianMatrix
MathJSON JacobianMatrix · (any, any?) -> value
JacobianMatrix(fs, vars): the matrix of partial derivatives
∂fᵢ/∂xⱼ, one row per function and one column per variable.
fs is a list of expressions. A single (non-list) expression is the
gradient case: the result is the flat vector [∂f/∂x₁, …, ∂f/∂xₙ].
vars is a list of symbols and may be omitted, in which case the
free variables of fs are used, in lexicographic order.
Example: JacobianMatrix([x^2 y, x + z], [x, y, z]).
limit
MathJSON Limit · (function, point: number, direction: number?) -> number
Limit of a function
Limits
(index: symbol, lower: value, upper: value) -> tuple
Limits of a function
nd
MathJSON ND · (function, at: number) -> list<number> | number | tuple
Numerical derivative evaluated at a point.
ndSolve
MathJSON NDSolve · (expression, symbol, limits: symbol | tuple, number, number?) -> list
Numerical differential equation solver.
ndSolveFunction
MathJSON NDSolveFunction · (expression, symbol, limits: symbol | tuple, number) -> function
Numerically solve an ordinary differential equation and return the solution as an applicable function (a Function literal wrapping an InterpolatingFunction), usable at any point of the integration interval. Same arguments as NDSolve, without the sample count.
nIntegrate
MathJSON NIntegrate · (function, lower: number, upper: number) -> number
Numerical approximation of a definite integral.
nLimit
MathJSON NLimit · (function, point: number, direction: number?) -> number
Numerical approximation of the limit of a function
normal
MathJSON Normal · (value) -> value
Strip Big-O remainder terms from a series, yielding the truncated polynomial. Example: Normal(Series(\sin x, x)) → x - x^3/6 + x^5/120
polygonContour
MathJSON PolygonContour · (vertices: list<complex>, orientation: integer?) -> expression
Simple closed polygon: a list of complex vertices in traversal order, with optional orientation override (+1 or -1).
rSolve
MathJSON RSolve · (expression, symbol, symbol) -> expression
Symbolic recurrence equation solver.
realLineContour
MathJSON RealLineContour · (principalValue: boolean?) -> expression
The real axis from minus infinity to infinity. Pass True to explicitly request a Cauchy principal value.
rectangleContour
MathJSON RectangleContour · (lowerLeft: complex, upperRight: complex, orientation: integer?) -> expression
Closed rectangle: lower-left and upper-right complex corners, optional orientation (+1 or -1).
residue
MathJSON Residue · (expression, variable: symbol, point: value) -> number
Residue of a function at a point (the coefficient of (x-a)⁻¹ in its Laurent expansion)
series
MathJSON Series · (expression, variable: symbol?, point: value?, order: number?) -> number
Taylor series expansion of an expression about a point (or an asymptotic expansion at ±∞), including Laurent, Puiseux (fractional-power), and log-aware expansions at poles and branch points. Only essential singularities, irrational exponents, and nested/reciprocal logarithms are left unevaluated. Example: Series(\sin x, x) → x - x^3/6 + x^5/120 + O(x^7)