This has been so frustrating, My problem was that within a newly constructed conda python36 environment, jupyter refused to load “seaborn” - even though seaborn was installed within that environment. It seemed to be able to import plenty of other files from the same environment — for example numpy and pandas but just not seaborn. I tried many of the fixes suggested here and on other threads without success. Until I realised that Jupyter was not running kernel python from within that environment but running the system python as kernel. Even though a decent looking kernel and kernel.json were already present in the environment. It was only after reading this part of the ipython documentation: https://ipython.readthedocs.io/en/latest/install/kernel_install.html#kernels-for-different-environments and using these commands:

source activate other-env
python -m ipykernel install --user --name other-env --display-name "Python (other-env)"

我能让一切顺利进行。(我实际上没有使用-user变量)。

我还没有想到的一件事是如何将默认的python设置为“python (other-env)”。目前，从主屏幕打开的现有.ipynb文件将使用系统python。我必须使用内核菜单“更改内核”来选择环境python。

虽然@coolscitist的回答对我来说是有效的，但也有一种方法不会让你的内核环境与完整的jupyter包+deps混淆。 它在ipython文档中有描述，(我怀疑)只有在非基础环境中运行笔记本服务器时才有必要。

conda activate name_of_your_kernel_env
conda install ipykernel
python -m ipykernel install --prefix=/home/your_username/.conda/envs/name_of_your_jupyter_server_env --name 'name_of_your_kernel_env'

你可以用

conda activate name_of_your_jupyter_server_env 
jupyter kernelspec list

我们在这个问题上做了很多努力，以下是对我们有效的方法。如果你使用conda-forge通道，确保你使用的是从conda-forge更新的包是很重要的，即使是在你的Miniconda根环境中。

所以安装Miniconda，然后做:

conda config --add channels conda-forge --force
conda update --all  -y
conda install nb_conda_kernels -y
conda env create -f custom_env.yml -q --force
jupyter notebook

你的自定义环境将作为可用的内核显示在Jupyter中，只要你的custom_env中列出了ipykernel以供安装。Yml文件，就像这个例子:

name: bqplot
channels:
- conda-forge
- defaults
dependencies:
- python>=3.6
- bqplot
- ipykernel

为了证明它适用于许多自定义环境，这里有一个Windows屏幕截图:

我不得不运行前3个答案中提到的所有命令来让它工作:

conda install jupyter
conda install nb_conda
conda install ipykernel
python -m ipykernel install --user --name mykernel

我也遇到了同样的问题，我的新conda环境myenv不能被选为内核或新笔记本。在env中运行jupter notebook也得到了相同的结果。

我的解决方案，以及我了解到Jupyter笔记本如何识别conda-envs和内核:

使用conda将jupyter和ipython安装到myenv:

conda install -n myenv ipython jupyter

在那之后，在任何env之外运行jupter notebook时，将myenv与我以前的环境一起列为内核。

Python [conda env:old]
Python [conda env:myenv]

启动环境后运行笔记本:

source activate myenv
jupyter notebook

隐藏所有其他环境内核，只显示我的语言内核:

python 2
python 3
R

按照iPython文档中的说明，将不同的conda环境添加到Jupyter Notebook中可供选择的内核列表中。总之，安装完ipykernel后，必须在终端中逐个激活conda环境，执行命令python -m ipykernel install——user——name myenv——display-name " python (myenv)"，其中myenv就是要添加的环境(内核)。