User:Airpmb/sandbox

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Getting Help[edit]

In MATLAB, the help command provides brief help on a given command/function, e.g.:

>> help sin

sin    Sine of argument in radians.

   sin(X) is the sine of the elements of X.

   See also asin, sind.

   Reference page for sin

In Julia, to get help, press the ? key in the REPL (or IJulia) at the start of a line, which switches the prompt to help?> . Type the name of a function and press ↵ Enter to show help for that function. Let's try help for the sin function:

help?> sin
search: sin sinh sind sinc sinpi sincos asin using isinf asinh asind isinteger

  sin(x)


  Compute sine of x, where x is in radians.

  ─────────────────────────────────────────────────────────────────────────────────

  sin(A::AbstractMatrix)


  Compute the matrix sine of a square matrix A.

  If A is symmetric or Hermitian, its eigendecomposition (eigen) is used to compute
  the sine. Otherwise, the sine is determined by calling exp.

  Examples
  ≡≡≡≡≡≡≡≡≡≡

  julia> sin(fill(1.0, (2,2)))
  2×2 Array{Float64,2}:
   0.454649  0.454649
   0.454649  0.454649