`num2ruler`

Converts numeric values to the data type that an axis ruler uses.

Category: Graphics > Formatting and Annotation

Syntax

data = num2ruler(num, ruler)

Converts the numbers num to values of the type shown on the ruler, such as datetime on a time axis.

Description

Axes with datetime, duration or categorical data store positions as plain numbers internally. num2ruler translates such a position back to the value a reader sees on the axis, and ruler2num goes the other way.

This is useful when a property such as a limit or a tick is stored numerically but the code needs the corresponding date.

Input arguments

num: Numeric array of positions along the axis.
ruler: An axis ruler, for example ax.XAxis or ax.YAxis.

Output arguments

data: Values in the ruler's own type. For a numeric ruler they are the numbers unchanged.

Example

Position on a date axis

t = datetime(2024,1,1) + days(0:4);
plot(t, [1 4 2 5 3])
ax = gca;
n = ruler2num(t(3), ax.XAxis)
d = num2ruler(n, ax.XAxis)

Output

n = 2
d = datetime
   03-Jan-2024

Notes

In MatLivre the conversion is available for numeric and datetime rulers. Other ruler types are not converted.

num2ruler