how to plot waterfall FFT

I have time and force discrete values and want a waterfall plot(time, frequency and amplitude). so how can i do that. is these 2 inputs are sufficient for plotting

Answer 1

[pfb]

have you taken a look at the documentation of the "waterfall" function? You can do that by typing

 doc waterfall

I'm not sure why you say you have 2 inputs (time, frequency and amplitude add to 3, in my book).

Anyway waterfall works with either 1 (matrix) or 3 basic inputs.

[Gaurav Bhakar]

i have seen that doc file... i have 50000 time and force values and i want to show 3-d plotting having time , frequency and amplitude as 3 axis. that is possible by using "window". but i dont know how to do that. if you have any code if will be very help full for completing my college report.

by the way thanks for response

Answer 2

[Star Strider]

Use the spectrogram function to create a time-frequency representation of your force data. Then you can use the waterfall plot. Otherwise, with only time or frequency and force, you do not have enough data for a waterfall plot. You can only plot a 2D fft.

[Gaurav Bhakar]

thanks but by any means if i can give "window" to my data and use hold on command. will it work

[Star Strider]

See the documentation for the spectrogram function (Signal Processing Toolbox). It has a default window function, and allows you to choose from a library of others. With spectrogram, you would not need to use the hold function, unless you are plotting something on top of the plot.