Change Default kernel in jupyter notebook

Question

I am using ipython 6.4.0 on ubuntu 20.04 and using jupyter kernelspec list , I found, there are 2 kernels :

1. practice_applied_ai
2. python3

When I open any .ipynb file, it directly opens in "python3" but I want to open it in "practice_applied_ai" because I created virtual environment practice_applied_ai and only in this kernel I can import Tensorflow 2.2.0 for my work.
My question is, Is there any way to change my default kernel without removing any kernel ?

Answer 1

See this answer on GitHub. As explained there:

the default kernel name is rarely used. It really only comes into play when a request is received to start a kernel and the kernel name is not specified in the request payload. Since both Notebook and Lab UIs essentially require the user to select a kernel (for new notebooks), it doesn't really come into play.

Put c.MappingKernelManager.default_kernel_name='newDefault' in config file.

To confirm the default is in place, hit the kernelspecs REST API of your running notebook server (e.g., http://localhost:8888/api/kernelspecs) and you should see the default kernel name as the first entry in the returned payload.

Answer 2

jupyter notebook --generate-config 

open the generated config file change
change this line to your desired kernel

#c.MultiKernelManager.default_kernel_name = 'python3' 

like

c.MultiKernelManager.default_kernel_name = 'py38' 

Answer 3

Yes this is possible via the .ipynb file itself. Set the following variables in the metadata, specifically the name which identifies the kernel

  "metadata": {
   "kernelspec": {
   "display_name": "Python 3 (PyTorch 1.6 Python 3.6 CPU Optimized)",
   "language": "python",
   "name": "python3__SAGEMAKER_INTERNAL__arn:aws:sagemaker:us-east-1:081325390199:image/pytorch-1.6-cpu-py36-ubuntu16.04-v1"
   },
   "language_info": {
    "codemirror_mode": {

Answer 4

Not sure how to change the default kernel, but you can change the kernel being used in a notebook, after opening the notebook, as explained in this site.
Open the notebook. Then navigate to Kernel -> Change Kernel and select the kernel you want to use.