Hi,(adsbygoogle = window.adsbygoogle || []).push({});

I am a neophyte in Discrete Fourier Transform and I am procticing with discrete Sine-transform.

Specifically I want to calculate $$ \mathcal{F}_s \lbrace x \cdot e^{-x^2} \rbrace = \int\limits_{0}^{\infty } x \cdot e^{-x^2} \cdot \sin\left(x\right)\, \mathrm{d}x

= \frac{1}{2} \pi^2 \omega e^{- \frac{1}{4} \pi^2 \omega^2} $$

I am using the FFTw library and with a 64 points I get a very poor result. Can anybody please help to improve it?

This is my C++ code, plot and numerical data are attached.

Thank you very much in advance

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# A Help with Discrete Sine Transform

Have something to add?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**