I'm new to Pure Data and am trying to understand the results of real and complex FFT. I want to create an array of values and feed them through the FFT patches and examine the results. What I need to know is how to convert my array data into a signal for FFT and how to convert the output back to an array for examination and printing.

Would appreciate any guidance on this matter.

Many thanks.

Hi and welcome to this forum.

I would also suggest you have a look on this tutorial of doing FFT in Pure Data: http://www.pd-tutorial.com/english/ch03s08.html

Cheers,
Gilberto

Thanks for your reply and sorry for putting post in wrong area.

I have already looked at the guide you suggest and still can't find out how to create my own array of data (for example an array of 32 floats) and pass it through the FFT patch. All the examples I've seen derive their input from osc~ or phasor~. My data may or may not be sinusoidal and I'm experimenting with Fourier transforms to better understand the process of forward and inverse transformation and to compare the results with my own program in C# in which I'm trying to write a pitch detection procedure.

Thanks for your reply and sorry for putting post in wrong area.

No worries!

still can't find out how to create my own array of data (for example an array of 32 floats) and pass it through the FFT patch

I think I now understand what you want to do. Well, the FFT objects in Pd are signal objects, so you have to somehow transform your data into a signal. Probably what you want to do is to create an array with your data and use [tabreceive~] to transform them into a signal block that is constantly repeated.

Cheers,
Gilberto

Giberto, [tabreceive~] is exactly what I need , many thanks.

How exactly is tabreceive~ used? I haven't come across it before and can't find any decent documentation on it.

@LiamG Well, it is a similar object to a [tabread~], but with the difference that while the indexes of the array can be controlled with a signal in [tabread~], with [tabreceive~] they are constantly looped automatically (that is, you just hook its outlet to something and you are good to go). It's very useful for things such as creating a window function in FFT. Have a look on that link I posted in my first reply here for some examples of usage of [tabreceive~].