ecg_process Bug when no R peaks detected

[filipy1]

Describe the bug
Failure to run ecg_process when inside the function ecg_peaks doesn’t find any peaks, doesn’t handle rpeaks being an empty array (it does handle rpeaks is None).

Reproduce

1. Load an ECG lead data with asystoles/low voltage/very wide QRS (I use 500 Hz sampling)
2. Try and run the ecg_process function
3. See error

Expected behaviour
I expected the function to return only the data it can calculate without detecting rpeaks

Screenshots
Example of ECG with error

System Specifications

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[welcome]

Hi 👋 Thanks for reaching out and opening your first issue here! We'll try to come back to you as soon as possible. ❤️

[DerAndereJohannes]

Hi! Thank you for your error report. To make it easier for us, would you mind sending in some example code to replicate the issue (ideally also with some data too)? For example the following should work fine:

import neurokit2

SAMPLING_RATE = 500

signal = nk.ecg_simulate(sampling_rate=SAMPLING_RATE)
signals, info = nk.ecg_process(signal, sampling_rate=SAMPLING_RATE)

If it is a problem with peaks etc. We will be able to focus more on the core issue with the error traceback that you receive.

Thanks in advance.

[filipy1]

Added some info to the original issue, thanks for the reply

This is the start of the function I run adn where it fails
def process_ecg_lead(ecg_signal_lead, sampling_rate=500):
signals, info = nk.ecg_process(ecg_signal_lead, sampling_rate=sampling_rate)

Traceback (most recent call last):

File "Code_file.py", line 106, in

average_beat = process_ecg_lead(ecg_signal_lead)

               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

File "Code_file.py", line 16, in process_ecg_lead

signals, info = nk.ecg_process(ecg_signal_lead, sampling_rate=sampling_rate)

                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

File general.venv\Lib\site-packages\neurokit2\ecg\ecg_process.py", line 112, in ecg_process

quality = ecg_quality(

          ^^^^^^^^^^^^

File general.venv\Lib\site-packages\neurokit2\ecg\ecg_quality.py", line 120, in ecg_quality

quality = _ecg_quality_averageQRS(

          ^^^^^^^^^^^^^^^^^^^^^^^^

File " general.venv\Lib\site-packages\neurokit2\ecg\ecg_quality.py", line 164, in _ecg_quality_averageQRS

heartbeats = ecg_segment(ecg_cleaned, rpeaks, sampling_rate)

             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

File " general.venv\Lib\site-packages\neurokit2\ecg\ecg_segment.py", line 64, in ecg_segment

heartbeats = epochs_create(

             ^^^^^^^^^^^^^^

File " general.venv\Lib\site-packages\neurokit2\epochs\epochs_create.py", line 158, in epochs_create

parameters = listify(

             ^^^^^^^^

File general.venv\Lib\site-packages\neurokit2\misc\listify.py", line 31, in listify

args[key] = _multiply_list(value, maxi)

            ^^^^^^^^^^^^^^^^^^^^^^^^^^^

File "general.venv\Lib\site-packages\neurokit2\misc\listify.py", line 39, in _multiply_list

q, r = divmod(length, len(lst))

       ^^^^^^^^^^^^^^^^^^^^^^^^

ZeroDivisionError: integer division or modulo by zero

[stale]

Is this still relevant? If so, what is blocking it? Is there anything you can do to help move it forward?

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[DerAndereJohannes]

Thank you for the traceback. Yes, I think we should better handle the process command when there are no peaks available. I will try to add a warning and then skip any command that requires peaks to be present. I will reference this issue in a commit.