Probability and statistics are used to model uncertainty from a variety of sources, such as incomplete or simplified models. Yet you can build useful models for aggregate or ...

BesselI[n, z] gives the modified Bessel function of the first kind I_n (z).

BesselK[n, z] gives the modified Bessel function of the second kind K_n (z).

BesselY[n, z] gives the Bessel function of the second kind Y_n (z).

Definition[symbol] prints as the definitions given for a symbol.

DirectedEdges is an option for Graph, GraphPlot, and related functions that specifies whether edges should be taken to be directed.

Dt[f, x] gives the total derivative d f/d x. Dt[f] gives the total differential d f. Dt[f, {x, n}] gives the multiple derivative d^n f/d x^n. Dt[f, x_1, x_2, ...] gives d/d ...

FindGraphIsomorphism[g_1, g_2] finds an isomorphism that maps the graph g_1 to g_2 by renaming vertices.

FrameTicksStyle is an option for 2D graphics functions that specifies how frame ticks should be rendered.

GraphicsGrid[{{g_11, g_12, ...}, ...}] generates a graphic in which the g_ij are laid out in a two-dimensional grid.