Function Repository Resource:

HashHue

Source Notebook

Map an expression to a color based on a hash

Contributed by: Bob Sandheinrich

ResourceFunction["HashHue"][expr]

gives a Hue based on the expression expr.

ResourceFunction["HashHue"][expr,type]

uses the specified hash type.

Details and Options

ResourceFunction["HashHue"] accepts the same values of type as Hash. The default is "Expression".

ResourceFunction["HashHue"] always gives the same Hue for the same input expression.

Coloring complex expressions makes differences stand out much faster than viewing them normally.

Examples

Basic Examples (2)

Get a color for an expression:

In[1]:=

Out[1]=

Sometime differences in values are hard to see visually:

In[2]:=

$values = RandomReal[10^7, WorkingPrecision -> 20] + {0, 0, 0, 10^3, 0, 0, 0, 0}$

Out[2]=

Make different values standout visually:

In[3]:=

Out[3]=

Scope (3)

Data with text fields can take up space:

In[4]:=

Out[4]=

Instead, visualize the data with colors where identical values always match:

In[5]:=

Out[5]=

Create an index for interpreting the color:

In[6]:=

Out[6]=

Applications (1)

Create a docked cell that shows your current Wolfram Language status:

In[7]:=

statusCell[] := Cell[BoxData[
ToBoxes[Grid[{Style[#, ResourceFunction[
"HashHue"][#]] & /@ {$VersionNumber, $CloudConnected, $WolframID}}, Spacings -> 5]]], "Output"]

In[8]:=

Version History

1.0.0 – 14 August 2019

Author Notes

Extending this to set all HSB (or RGB) values in a smart way would extend the used color space and increase the typical distance between results.

License Information

This work is licensed under a Creative Commons Attribution 4.0 International License