How to extract state values of function slewrate() / Get Upper state values bimodal waveform

Hello,

The builtin function slewrate() indicates in a plot the upper state and the lower state levels. However, I could not find a parameter on how to extract those values. I mean, if the plot shows those values, it should be possible to get them as a value..

Or maybe there is another function/method ? I have a square waveform with overshoot (both on the high and low side) and want to get the settled values from top and bottom.

Answer 1

[Sumukh]

Hi Jemp.

The “slewrate” function has few name-value pair arguments that can be passed into it, as per the following documentation:

https://www.mathworks.com/help/releases/R2020a/signal/ref/slewrate.html#:~:text=Name%2DValue%20Pair%20Arguments

One such name-value pair is for passing “StateLevels” argument. If nothing is passed here, the “slewrate” function uses states estimated by the “statelevels” function, which uses a histogram method to estimate the state levels of given bilevel waveform. You can try out the following line of code to get the state levels:

levels = statelevels(y) % y should be declared before running this.

The “levels” variable is a 1x2 vector that has the lower and upper state levels of given bilevel waveform in variable “y”. Please refer to the following documentation for further understanding:

https://www.mathworks.com/help/releases/R2020a/signal/ref/statelevels.html?searchHighlight=statelevels&s_tid=doc_srchtitle

I hope this solves the issue.