Axis APIs - Value Axis vs. Category Axis

SciChart 2D iOS Features several axis types which could be Value or Category. All inherit from SCIAxisBase. So what’s the difference between Value and Category Axes? An explanation is given below.

Given the data:

Age (X-Axis)	Cats	Dogs	Fish
1	7	7	8
9	6	5	7
10	5	4	3
20	4	3	2

A Value X-Axis and Category X-Axis would display the data differently:

Category X-Axis	Value X-Axis

The fundamental difference is a Value-Axis uses the X-Value to compute distance on the XAxis, whereas a Category-Axis uses the X-Index. Value-Axis are primarily used in scientific software where Category–Axis are typically used in financial software (e.g. stock charts).

SciChart features both Value-Axis and Category-Axis types.

Axis Type	Value or Category Axis
SCINumericAxis	Value Axis
SCILogarithmicNumericAxis	Value Axis
SCIDateAxis	Value Axis
SCICategoryDateAxis	Category Axis

For more information, refer to the Axis APIs article.