How you should install scikit-image
depends on your needs and skills:
MacOS 64-bit installer即为 Mac OS X 系统的 Python 安装包。点击该链接,下载完成后得到一个 python-3.8.1-macosx10.9.pkg 安装包。 双击 python-3.8.1-macosx10.9.pkg 就进入了 Python 安装向导,然后按照向导一步一步向下安装,一切保持默认即可。. May 12, 2021 python -m pip install SomePackage1.0.4 # specific version python -m pip install 'SomePackage=1.0.4' # minimum version. Normally, if a suitable module is already installed, attempting to install it again will have no effect. Upgrading existing modules must be requested explicitly: python -m pip install -upgrade SomePackage.
Simplest solution:scientific Python distribution.
If you can install Python packages and work in virtual environments:
Easy solution but with pitfalls: system package manager (yum, apt, …).
You’re looking to contribute to scikit-image.
Supported platforms¶
Windows 64-bit on x86 processors
Mac OS X on x86 processors
Linux 64-bit on x86 processors
For information on other platforms, see other platforms.
Version check¶
To see whether scikit-image
is already installed or to check if an install hasworked, run the following in a Python shell or Jupyter notebook:
or, from the command line:
(Try python3
if python
is unsuccessful.)
You’ll see the version number if scikit-image
is installed andan error message otherwise.
Scientific Python distributions¶
In a single install these give you Python,scikit-image
and libraries it depends on, and other useful scientificpackages. They install into an isolated environment, so they won’t conflictwith any existing installed programs.
Drawbacks are that the install can be large and you may not getthe most recent scikit-image
.
We recommend one of these distributions:
When using the scikit-image
documentation, make sure it’s for the version you’ve installed (seeVersion check above).
Installation via pip and conda¶
These install only scikit-image
and its dependencies; pip has an option toinclude related packages.
pip¶
Prerequisites to a pip install: You’re able to use your system’s command line toinstall packages and are using avirtual environment(any ofseveral).
While it is possible to use pip without a virtual environment, it is not advised:virtual environments create a clean Python environment that does not interferewith any existing system installation, can be easily removed, and contain onlythe package versions your application needs. They help avoid a commonchallenge known asdependency hell.
To install the current scikit-image
you’ll need at least Python 3.6. Ifyour Python is older, pip will find the most recent compatible version.
To include a selection of other scientific Python packages that expandscikit-image
’s capabilities to include, e.g., parallel processing, youcan install the package scikit-image[optional]
:
Warning
Please do not use the command sudo
and pip
together as pip
mayoverwrite critical system libraries which may require you to reinstall youroperating system.
conda¶
Install Glob For Python In Mac Download
Miniconda is a bare-essentials version of the Anaconda package; you’ll need toinstall packages like scikit-image
yourself. Like Anaconda, it installsPython and provides virtual environments.
conda-forge, a conda channel maintainedwith the latest
scikit-image
package
Once you have your conda environment set up, you can install scikit-image
with the command:
System package managers¶
Using a package manager (yum
, apt-get
, etc.) to install scikit-image
or other Python packages is not your best option:
You’re likely to get an older version.
You’ll probably want to make updates and add new packages outside ofthe package manager, leaving you with the same kind ofdependency conflicts you see when using pip without a virtual environment.
There’s an added risk because operating systems use Python, so if youmake system-wide Python changes (installing as root or using sudo),you can break the operating system.
Downloading all demo datasets¶
Some of the data used in our examples is hosted online and is not installedby default by the procedures explained above. Data are downloaded once, at thefirst call, but this requires an internet connection. If you prefer downloadingall the demo datasets to be able to work offline, you can run this command:
or call download_all()
in your favourite interactive Python environment(IPython, Jupyter notebook, …).
Other platforms¶
We still support Windows 32-bit on x86 processors but urge switchingto Windows 64-bit.
Unsupported platforms include:
Linux on 32-bit x86 processors.
Linux on 32-bit on ARM processors (Raspberry Pi running Raspbian):
While we do not officially support this distribution, we point users topiwheelsand theirscikit-image’s specific page.
You may need to install additional system dependencies listed forimagecodecs.Seeissue 4721.
Linux on 64-bit ARM processors (Nvidia Jetson):
Follow the conversation onissue 4705.
Although these platforms lack official support, many of the coredevelopers have experience with them and can help with questions.
If you want to install on an unsupported platform, trybuilding from source.
Tell us which other platforms you’d like to see scikit-image
on!We are very interested in how scikit-image
getsused.
If you’d like to package scikit-image
for an as-yet-unsupported platform,reach out on GitHub.
Additional help¶
If you still have questions, reach out through
our forum on image.sc
our mailing list
our chat channel
To suggest a change in these instructions,please open an issue on GitHub.
This section covers the basics of how to install Python packages.
It’s important to note that the term “package” in this context is being used todescribe a bundle of software to be installed (i.e. as a synonym for adistribution). It does not to refer to the kindof package that you import in your Python source code(i.e. a container of modules). It is common in the Python community to refer toa distribution using the term “package”. Usingthe term “distribution” is often not preferred, because it can easily beconfused with a Linux distribution, or another larger software distributionlike Python itself.
Contents
This section describes the steps to follow before installing other Pythonpackages.
Before you go any further, make sure you have Python and that the expectedversion is available from your command line. You can check this by running:
You should get some output like Python3.6.3
. If you do not have Python,please install the latest 3.x version from python.org or refer to theInstalling Python section of the Hitchhiker’s Guide to Python.
Note
If you’re a newcomer and you get an error like this:
It’s because this command and other suggested commands in this tutorialare intended to be run in a shell (also called a terminal orconsole). See the Python for Beginners getting started tutorial foran introduction to using your operating system’s shell and interacting withPython.
Note
If you’re using an enhanced shell like IPython or the Jupyternotebook, you can run system commands like those in this tutorial byprefacing them with a !
character:
It’s recommended to write {sys.executable}
rather than plain python
inorder to ensure that commands are run in the Python installation matchingthe currently running notebook (which may not be the same Pythoninstallation that the python
command refers to).
Note
Due to the way most Linux distributions are handling the Python 3migration, Linux users using the system Python without creating a virtualenvironment first should replace the python
command in this tutorialwith python3
and the python-mpip
command with python3-mpip--user
. Do notrun any of the commands in this tutorial with sudo
: if you get apermissions error, come back to the section on creating virtual environments,set one up, and then continue with the tutorial as written.
Additionally, you’ll need to make sure you have pip available. You cancheck this by running:
If you installed Python from source, with an installer from python.org, orvia Homebrew you should already have pip. If you’re on Linux and installedusing your OS package manager, you may have to install pip separately, seeInstalling pip/setuptools/wheel with Linux Package Managers.
If pip
isn’t already installed, then first try to bootstrap it from thestandard library:
If that still doesn’t allow you to run python-mpip
:
Securely Download get-pip.py1
Run
pythonget-pip.py
. 2 This will install or upgrade pip.Additionally, it will install setuptools and wheel if they’renot installed already.Warning
Be cautious if you’re using a Python install that’s managed by youroperating system or another package manager. get-pip.py does notcoordinate with those tools, and may leave your system in aninconsistent state. You can use
pythonget-pip.py--prefix=/usr/local/
to install in/usr/local
which is designed for locally-installedsoftware.
While pip
alone is sufficient to install from pre-built binary archives,up to date copies of the setuptools
and wheel
projects are usefulto ensure you can also install from source archives:
See section below for details,but here’s the basic venv3 command to use on a typical Linux system:
This will create a new virtual environment in the tutorial_env
subdirectory,and configure the current shell to use it as the default python
environment.
Python “Virtual Environments” allow Python packages to be installed in an isolated location for a particular application,rather than being installed globally. If you are looking to safely installglobal command line tools,see Installing stand alone command line tools.
Imagine you have an application that needs version 1 of LibFoo, but anotherapplication requires version 2. How can you use both these applications? If youinstall everything into /usr/lib/python3.6/site-packages (or whatever yourplatform’s standard location is), it’s easy to end up in a situation where youunintentionally upgrade an application that shouldn’t be upgraded.
Or more generally, what if you want to install an application and leave it be?If an application works, any change in its libraries or the versions of thoselibraries can break the application.
Also, what if you can’t install packages into theglobal site-packages directory? For instance, on a shared host.
In all these cases, virtual environments can help you. They have their owninstallation directories and they don’t share libraries with other virtualenvironments.
Currently, there are two common tools for creating Python virtual environments:
venv is available by default in Python 3.3 and later, and installspip and setuptools into created virtual environments inPython 3.4 and later.
virtualenv needs to be installed separately, but supports Python 2.7+and Python 3.3+, and pip, setuptools and wheel arealways installed into created virtual environments by default (regardless ofPython version).
The basic usage is like so:
Using venv:
Using virtualenv:
For more information, see the venv docs or the virtualenv docs.
The use of source under Unix shells ensuresthat the virtual environment’s variables are set within the currentshell, and not in a subprocess (which then disappears, having nouseful effect).
In both of the above cases, Windows users should _not_ use thesource command, but should rather run the activatescript directly from the command shell like so:
Managing multiple virtual environments directly can become tedious, so thedependency management tutorial introduces ahigher level tool, Pipenv, that automatically manages a separatevirtual environment for each project and application that you work on.
pip is the recommended installer. Below, we’ll cover the most commonusage scenarios. For more detail, see the pip docs,which includes a complete Reference Guide.
The most common usage of pip is to install from the Python PackageIndex using a requirement specifier. Generally speaking, a requirement specifier iscomposed of a project name followed by an optional version specifier. PEP 440 contains a fullspecificationof the currently supported specifiers. Below are some examples.
To install the latest version of “SomeProject”:
To install a specific version:
To install greater than or equal to one version and less than another:
To install a version that’s “compatible”with a certain version: 4
Install Glob For Python In Mac Key
In this case, this means to install any version “1.4.*” version that’s also“>=1.4.2”.
pip can install from either Source Distributions (sdist) or Wheels, but if both are presenton PyPI, pip will prefer a compatible wheel. You can overridepip`s default behavior by e.g. using its –no-binary option.
Wheels are a pre-built distribution format that provides faster installation compared to SourceDistributions (sdist), especially when aproject contains compiled extensions.
If pip does not find a wheel to install, it will locally build a wheeland cache it for future installs, instead of rebuilding the source distributionin the future.
Upgrade an already installed SomeProject
to the latest from PyPI.
To install packages that are isolated to thecurrent user, use the --user
flag:
For more information see the User Installs sectionfrom the pip docs.
Note that the --user
flag has no effect when inside a virtual environment- all installation commands will affect the virtual environment.
If SomeProject
defines any command-line scripts or console entry points,--user
will cause them to be installed inside the user base’s binarydirectory, which may or may not already be present in your shell’sPATH
. (Starting in version 10, pip displays a warning wheninstalling any scripts to a directory outside PATH
.) If the scriptsare not available in your shell after installation, you’ll need to add thedirectory to your PATH
:
On Linux and macOS you can find the user base binary directory by running
python-msite--user-base
and addingbin
to the end. For example,this will typically print~/.local
(with~
expanded to the absolutepath to your home directory) so you’ll need to add~/.local/bin
to yourPATH
. You can set yourPATH
permanently by modifying ~/.profile.On Windows you can find the user base binary directory by running
py-msite--user-site
and replacingsite-packages
withScripts
. Forexample, this could returnC:UsersUsernameAppDataRoamingPython36site-packages
so you wouldneed to set yourPATH
to includeC:UsersUsernameAppDataRoamingPython36Scripts
. You can set your userPATH
permanently in the Control Panel. You may need to log out for thePATH
changes to take effect.
Install a list of requirements specified in a Requirements File.
Install a project from VCS in “editable” mode. For a full breakdown of thesyntax, see pip’s section on VCS Support.
Install from an alternate index
Search an additional index during install, in addition to PyPI
Installing from local src in Development Mode,i.e. in such a way that the project appears to be installed, but yet isstill editable from the src tree.
You can also install normally from src
Install a particular source archive file.
Install from a local directory containing archives (and don’t check PyPI)
To install from other data sources (for example Amazon S3 storage) you cancreate a helper application that presents the data in a PEP 503 compliantindex format, and use the --extra-index-url
flag to direct pip to usethat index.
Find pre-release and development versions, in addition to stable versions. Bydefault, pip only finds stable versions.
Install setuptools extras.
“Secure” in this context means using a modern browser or atool like curl that verifies SSL certificates whendownloading from https URLs.
Depending on your platform, this may require root or Administratoraccess. pip is currently considering changing this by making userinstalls the default behavior.
Beginning with Python 3.4, venv
(a stdlib alternative tovirtualenv) will create virtualenv environments with pip
pre-installed, thereby making it an equal alternative tovirtualenv.
The compatible release specifier was accepted in PEP 440and support was released in setuptools v8.0 andpip v6.0