What does it mean to convert frequency domain into rectangular form?

Here:
http://www.dspguide.com/ch17/1.htm

A description on creating arbitrary magnitude response filter using iFFT is given.

There it's also said that:

"The next step is to take the Inverse DFT to move the filter into the time domain. The quickest way to do this is to convert the frequency domain to rectangular form, and then use the Inverse FFT."

What does it mean to convert the frequency domain to rectangular form?

mavaviljggroup@gmail.com writes:

> Here:
> http://www.dspguide.com/ch17/1.htm
>
> A description on creating arbitrary magnitude response filter using iFFT is given.
>
> There it's also said that:
>
> "The next step is to take the Inverse DFT to move the filter into the time domain. The quickest way to do this is to convert the frequency domain to rectangular form, and then use the Inverse FFT."
>
> What does it mean to convert the frequency domain to rectangular form?

Probably that you convert the complex samples from polar to rectangular
form. Basic complex variables.
-- 
Randy Yates, DSP/Embedded Firmware Developer
Digital Signal Labs
http://www.digitalsignallabs.com

Randy Yates  <yates@digitalsignallabs.com> wrote:

>mavaviljggroup@gmail.com writes:

>> http://www.dspguide.com/ch17/1.htm
>> [snip]
>> There it's also said that:

>> "The next step is to take the Inverse DFT to move the filter into the
>time domain. The quickest way to do this is to convert the frequency
>domain to rectangular form, and then use the Inverse FFT."

>> What does it mean to convert the frequency domain to rectangular form?

>Probably that you convert the complex samples from polar to rectangular
>form. Basic complex variables.

Perhaps, but since "Inverse DFT" and "Inverse FFT" are mathematically
the same thing, it is not logical that some extra step is needed
for the latter to implement the former.

Steve