bathtub

Plot bathtub curves

Since R2024a

Syntax

bathtub(obj,orientation)

bathtub(obj,orientation,position)

bathtub(___,Name=Value)

[x,y] = bathtub(___)

[x,y,h] = bathtub(___)

Description

bathtub(obj,orientation) plots the bathtub curves from the eye diagram object obj in the orientation specified by orientation.

bathtub(obj,orientation,position) plots the bathtub curve at the amplitude level or time specified by position.

bathtub(___,Name=Value) uses Name-Value pair arguments to plot the bathtub curves. Unspecified arguments take default values.

[x,y] = bathtub(___) returns the x-axis data and y-axis data for the bathtub curve but does not generate the plot.

[x,y,h] = bathtub(___) returns the x-axis data and y-axis data for the bathtub curve and generates the plot.

Input Arguments

obj — Eye diagram object

eyeDiagramSI object

Eye diagram object, specified as an eyeDiagramSI System object™. The eye diagram object is created as an accumulation of 2-D histograms from the eye diagram data.

orientation — Orientation of eye slices to create bathtub curve

Time (default) | Amplitude | Horizontal | Vertical

Orientation of the eye slices to create the bathtub curve, specified as one of these:

• Horizontal — Cumulative distribution function (CDF) of horizontal slices taken at the specified amplitude. It produces the same bathtub curve as when orientation is set to Time.

• Vertical — Cumulative distribution function (CDF) of vertical slices taken at the specified time. It produces the same bathtub curve as when orientation is set to Amplitude.

• Time — Cumulative distribution function (CDF) of eye slices taken at the specified amplitude.

• Amplitude — Cumulative distribution function (CDF) of eye slices taken at the specified time.

position — Position of eye slice to create bathtub curve

0 (default) | real valued vector

Position of the eye slice to create bathtub curve, specified as a real valued vector.

For a time/horizontal bathtub, this argument refers to the amplitude level to take the eye slices. For an amplitude/vertical bathtub, this argument refers to the time at which to take the eye slices.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: bathtub(obj,Horizontal,SER=1e-3) creates a horizontal bathtub curve at symbol error rate 1e-3 from the eye diagram object obj.

TimeUnit — Unit for time axis of plot and position

Seconds (default) | Samples | UI

Unit for the time axis of the plot and position, specified as seconds, samples, or UI.

Data Types: char

AmplitudeUnit — Unit for amplitude axis of plot and position

Amplitude (default) | Index

Unit for the amplitude axis of the plot and position, specified as amplitude or index.

Data Types: char

SER — Lowest symbol error rate in bathtub curve

0 (default) | scalar

Lowest symbol error rate to in the bathtub curve, specified at a scalar.

Data Types: double

Extrapolation — Extrapolation method to plot bathtub curve

none (default) | dualdirac | gaussian | linear | spline | pchip | makima

Extrapolation method to bathtub curve. For more information, see Extrapolation.

Data Types: char

Output Arguments

x — x-axis data of bathtub curve

vector

x-axis data of the bathtub curve, returned as a vector.

y — y-axis data of bathtub curve

vector

y-axis data of the bathtub curve, returned as a vector.

h — Graphics handle for bathtub plot

function handle

Graphics handle for the bathtub plot, returned as a function handle.

Version History

Introduced in R2024a