InTheRed.jl

This package overloads Base.show to change how numbers are printed:

• Negative numbers are red
• Zero is light gray
• Inf, NaN and missing are yellow
• Low-precision numbers (like Float32, Int16) are cyan, or magenta if negative, and
• Unsigned integers are printed both in hex and decimal.

The cutoff for "nearly zero" is controlled by e.g. threshold!(1e-16).

It also changes how vectors numbers are printed:

• Vectors of real numbers are displayed with a bar graph alongside their values.
• Vectors of complex numbers show their absolute value as a bar graph, and phase as a compass direction.
• Ranges print more detail, including the range constructor.

The point of this is to provide extra context while working at the REPL, without getting in your way. The bar graphs should occupy unused space to the right of the numbers in your terminal.

Examples

Copying text from the REPL loses the colours but keeps the graph:

julia> Float16[x..., Inf]
15-element Vector{Float16}:
  -0.777   #    ┥
  -0.6323  #    ┥
  -0.3936  #    ┥
   0.0     #    │
   0.649   #    ┝
   1.719   #    ┝╸
   3.482   #    ┝━
   6.39    #    ┝━╸
  11.18    #    ┝━━╸
  19.08    #    ┝━━━━
  32.12    #    ┝━━━━━━━
  53.6     #    ┝━━━━━━━━━━━━
  89.0     #    ┝━━━━━━━━━━━━━━━━━━━━
 147.4     #    ┝━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  Inf      #    ╪═▶

julia> reverse(1:10)
10-element StepRange{Int64, Int64}:
# range(10, 1, step=-1) === 10:-1:1
 10  #    ┝━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
  9  #    ┝━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╸
  8  #    ┝━━━━━━━━━━━━━━━━━━━━━━━━━━╸
  ⋮
  3  #    ┝━━━━━━━━━━
  2  #    ┝━━━━━━╸
  1  #    ┝━━━╸

For complex numbers, the graph shows phase and magnitude like this:

julia> cis.(range(0,2pi,9)) .* logrange(1/3,3,9) .|> ComplexF32
9-element Vector{ComplexF32}:
   0.33333334f0 + 0.0f0im          #   │➡┝━━━╸
   0.31020162f0 + 0.31020162f0im   #   │↗┝━━━━━
  3.5352508f-17 + 0.57735026f0im   #   │⬆┝━━━━━━╸
    -0.537285f0 + 0.537285f0im     #   │↖┝━━━━━━━━╸
         -1.0f0 + 1.2246469f-16im  #   │⬅┝━━━━━━━━━━━
   -0.9306049f0 - 0.9306049f0im    #   │↙┝━━━━━━━━━━━━━━╸
 -3.1817257f-16 - 1.7320508f0im    #   │⬇┝━━━━━━━━━━━━━━━━━━━
    1.6118549f0 - 1.6118549f0im    #   │↘┝━━━━━━━━━━━━━━━━━━━━━━━━━
          3.0f0 - 7.3478806f-16im  #   │➡┝━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Unsigned integers:

julia> 0x0c9
0x00c9  # == 201

julia> -ans
0xff37  # == 65335

Elsewhere

• OhMyREPL.jl changes the text you type at the prompt, instead of what is printed.

• UnicodePlots.jl allows much more complicated plotting as text.