更改conda環境下，pip包安裝默認路徑

pip 指定某個路徑安裝包

# 在dir路徑下，安裝numpy包
pip install -t dir numpy
pip install --target dir numpy

設置pip默認安裝路徑
1、查看目前默認安裝路徑

在這裏插入代碼片
python -m site
# 顯示內容
sys.path = [
    '/home/users/xxx/anaconda3/envs/gluon-cv',
    '/home/users/xxx/anaconda3/envs/gluon-cv/lib/python3.6/site-packages',
]
USER_BASE: '/home/users/xxx/.local' (exists)
USER_SITE: '/home/users/xxx/.local/lib/python3.6/site-packages' (exists)
ENABLE_USER_SITE: True

由於未知的原因，在gluon-cv這個環境下，默認安裝路徑指向了’/home/users/xxx/.local/lib/python3.6/site-packages’
2、重新設定USER_BASE和USER_SITE
首先conda激活環境，然後修改 site.py 中的USER_BASE和USER_SITE變量，site.py路徑：~/anaconda3/envs/gluon-cv/lib/python3.6/site.py，修改後內容如下：

ImportError exception, it is silently ignored.
"""

import sys
import os
import builtins
import _sitebuiltins

# Prefixes for site-packages; add additional prefixes like /usr/local here
PREFIXES = [sys.prefix, sys.exec_prefix]
# Enable per user site-packages directory
# set it to False to disable the feature or True to force the feature
ENABLE_USER_SITE = None

# for distutils.commands.install
# These values are initialized by the getuserbase() and getusersitepackages()
# functions, through the main() function when Python starts.
USER_SITE = '/home/users/xxx/anaconda3/envs/gluon-cv'
USER_BASE = '/home/users/xxx/anaconda3/envs/gluon-cv/lib/python3.6/site-packages'

修改後再次運行 python -m site 查看，輸出內容如下：

在這裏插入代碼片
sys.path = [
    '/home/users/xxx/anaconda3/envs/gluon-cv',
    '/home/users/xxx/anaconda3/envs/gluon-cv/lib/python3.6/site-packages',
]
USER_BASE: '/home/users/xxx/anaconda3/envs/gluon-cv/lib/python3.6/site-packages' (exists)
USER_SITE: '/home/users/xxx/anaconda3/envs/gluon-cv' (exists)
ENABLE_USER_SITE: True

這個時候pip默認安裝路徑就修改成功了~