CSV file writer - sampling frequency issue
Posted: Wed Mar 31, 2021 8:10 am
Hello!
I am trying to write certain data to a CSV file which is sampled every 0.1 seconds (10 Hz). However, for some reason, the CSV file writer box writes the sampling frequency to be 1 Hz in the header. The timestamps in the same file say otherwise - they have a step of 0.1s, so the frequency is obviously 10 Hz. This produces problems when I try to read from that file later on.
Is there any explanation why this is happening? I am using OpenVibe Acquisition Server to stream data from Matlab via LSL, and then I epoch the data with epoch duration of 3s, epoch interval 0.1s (that's why in the CSV file the timestamps are 0.1s apart = 10 Hz). After that, I process the data in some way.
But the data from Matlab is sent every 0.002 seconds, which does not correspond to the frequency of 1 Hz. I would just like to understand where does this 1 Hz sampling frequency come from even if I can't change it. Could it be that the processing steps after time-based epoching (filtering, averaging, DSP etc.) cause this?
Oh, and I use the latest version 3.0.0 OpenVibe.
Please help!!!
I am trying to write certain data to a CSV file which is sampled every 0.1 seconds (10 Hz). However, for some reason, the CSV file writer box writes the sampling frequency to be 1 Hz in the header. The timestamps in the same file say otherwise - they have a step of 0.1s, so the frequency is obviously 10 Hz. This produces problems when I try to read from that file later on.
Is there any explanation why this is happening? I am using OpenVibe Acquisition Server to stream data from Matlab via LSL, and then I epoch the data with epoch duration of 3s, epoch interval 0.1s (that's why in the CSV file the timestamps are 0.1s apart = 10 Hz). After that, I process the data in some way.
But the data from Matlab is sent every 0.002 seconds, which does not correspond to the frequency of 1 Hz. I would just like to understand where does this 1 Hz sampling frequency come from even if I can't change it. Could it be that the processing steps after time-based epoching (filtering, averaging, DSP etc.) cause this?
Oh, and I use the latest version 3.0.0 OpenVibe.
Please help!!!