MATHCAD - how do I change a function f(x) to a vector so that I can use it in subsequent evaluations (e.g. interpolate)?

[rmartin-2]

I have a time domain function (damped sine) in MATHCAD that needs to be fft, then attenuated by a frequency dependent vector. To do that I need to:

- perform fft on function

- interpolate the fft with the attenuation

I have tried VECTORIZED with no success. Can anyone help with creating a vector/matrix from a function?

[StuartBruff · Accepted solution]

Robert Martin wrote:

I have a time domain function (damped sine) in MATHCAD that needs to be fft, then attenuated by a frequency dependent vector. To do that I need to:

- perform fft on function

- interpolate the fft with the attenuation

I have tried VECTORIZED with no success. Can anyone help with creating a vector/matrix from a function?

Could you please post your worksheet so that others can see what you've done?

Thanks,

Stuart

[rmartin-2]

Stuart - unfortunately, the attached won't tell you much. As you can imagine, I have been trying lots of things; getting frustrated; deleting my attempts.

The worksheet simply defines a function of (t) to define a damped sine waveform with a fundamental frequency that can be adjusted (currently 10^4).

[StuartBruff]

Robert Martin wrote:

Stuart - unfortunately, the attached won't tell you much. As you can imagine, I have been trying lots of things; getting frustrated; deleting my attempts.

The worksheet simply defines a function of (t) to define a damped sine waveform with a fundamental frequency that can be adjusted (currently 10^4).

Is the attached something like what you are after?

Stuart

[rmartin-2]

Stuart - this works well.

As an aside - explanation of cfft is very useful. To date, when calculating FFT, I have been forcing everything to power of 2 in order to make fft work. Thank you. Bob