## Forums comp.dsp

## Array indexing in Matlab finally corrected after 30 years!

inI was glad to hear that Mathworks has finally corrected their array indexing scheme to start with 0 instead of 1, so they're now compatible with...

I was glad to hear that Mathworks has finally corrected their array indexing scheme to start with 0 instead of 1, so they're now compatible with all the other languages out in the real world. Apparently they knew all along that array indexes actually start at zero, but a bug in the initial release of the code caused the 'off by one' problem. An admission of such a glaring math error would ...

## Static library with -lm dumps core on run time

inUbuntu 64bit on an AMD C50 dual core The c program was initially compiled using dynamic linking and tested fine. I statically linked it...

Ubuntu 64bit on an AMD C50 dual core The c program was initially compiled using dynamic linking and tested fine. I statically linked it with gcc a.c b.c -o myprogramEXE -static -lm and also by putting the full path the 3rd time. I also tested with ldd. When executing it dumps core on the same input conditions as with dynamic linking and on the same environment! Why - what is the fi...

## Python question

inApropos to the question "Python for DSP" in comp.dsp (http:// www.dsprelated.com/showthread/comp.dsp/243722-1.php): How fully object-oriented...

Apropos to the question "Python for DSP" in comp.dsp (http:// www.dsprelated.com/showthread/comp.dsp/243722-1.php): How fully object-oriented is Python? I'm doing an app that really wants to be prototyped in something Scilab-ish (i.e., interpreted so it's easy to do graphs or computation on bits of it), but which is seriously challenging Scilab's sorta-object oriented-ness. I'm running...

## oversampled Fourier transform

inHello Forum, given a N-point window h(n), how do I create an oversampled Fourier transform H out of h(n)? I need to have very high resolution...

Hello Forum, given a N-point window h(n), how do I create an oversampled Fourier transform H out of h(n)? I need to have very high resolution of the H so that I can find out the magnitude of arbitrary frequency with little frequency error. This is what I did: to oversample h(n) with factor 2, I first sampled the window h with N * 2 points, and then simply FFT the 'new h' with N*2-point. But ...

## Matlab FFT Reconstruction from Physiologic Frequency-Varying Signal

inDSP Experts, I am analyzing a physiologic signal that has a varying fundamental frequency. To create a more accurate reconstruction from the...

DSP Experts, I am analyzing a physiologic signal that has a varying fundamental frequency. To create a more accurate reconstruction from the FFT, I wish to include the bins immediately and symmetrically on either side of the fundamental bins. I refer to this as the "distribution method." I am confident I have been able to do a reconstruction using the fundamental bins (a standard reconstruct...

## What is difference between OFDM and GFDM?

Hi, I am trying to understand the difference(s) between OFDM and GFDM which are used as a multicarrier modulation techniques in wireless...

Hi, I am trying to understand the difference(s) between OFDM and GFDM which are used as a multicarrier modulation techniques in wireless communication. As far as I know the OFDM uses the orthogonal subcarriers and the GFDM is with the non-orthogonal subcarriers when designing a transmitter. Could anyone please explain further about their design and differences? What is the purpose of using...

## FIR filter with initial conditions

inHey I am trying to write my own FIR filter in MATLAB for a project I am working on with the aim of eventually porting the project over to c...

Hey I am trying to write my own FIR filter in MATLAB for a project I am working on with the aim of eventually porting the project over to c (so I cannot use MATLAB built-in functions). The filter is taking smaller chunks of a large chunk of data and filtering them separately so I need to be able to set the initial conditions. Has anyone any idea how MATLAB uses the initial conditions, zi, inpu...

## [ FAR off topic ;] Competent reporting of electric utility problem

inI needed to ask a question of a *GROUP* who I trust and with which I have some credibility. I have a utility problem of some sort. I vainly...

I needed to ask a question of a *GROUP* who I trust and with which I have some credibility. I have a utility problem of some sort. I vainly attempted to have my "verbatim" problem description passed on to competent technical personnel. I've 3 years towards a BSEE and ~20 yrs as engineering tech &/or Jr Eng. What I observed was significant short term reduction of illumination pro...

## Python for DSP

inSeems that Python is catching on for some DSP work. The recent Coursera course co-sponsored by Julius Smith III used Python rather than...

Seems that Python is catching on for some DSP work. The recent Coursera course co-sponsored by Julius Smith III used Python rather than Matlab. I've searched for DSP libraries but there's kind of a confusing jumble. Some are just using SciPy. Does anyone know of specific Python libs that would extend SciPy's scope?

## Adaptive PIDF under closed-loop

inHi guys I know this not quite by the book of control theory, but i am looking into ways to implement an adaptive system onto my PIDF. Lets say...

Hi guys I know this not quite by the book of control theory, but i am looking into ways to implement an adaptive system onto my PIDF. Lets say (theoretical) that we dont have equations of state, hence we can't linearize the system around certain operating points. We can only do open-loop step response to estimate a optimal controller. The system is unstable and have complex poles. With that b...