Revert "Transition from setup.py to pyproject.toml (#199)"

This reverts commit e9b82f0.

README.rst

@@ -13,101 +13,31 @@ uncertainties
 .. image:: https://img.shields.io/github/actions/workflow/status/lmfit/uncertainties/python-package.yml?logo=github%20actions
    :target: https://github.com/lmfit/uncertainties/actions/workflows/python-package.yml
 
-``uncertainties`` allows **calculations** such as (2 +/- 0.1)*2 = 4 +/-
-0.2 to be **performed transparently**.  Much more complex mathematical
-expressions involving numbers with uncertainties can also be evaluated
-directly.
-
-The ``uncertainties`` package **takes the pain and complexity out**
-of uncertainty calculations.
-
-**Detailed information** about this package can be found on its `main
-website`_.
-
-Basic examples
---------------
-
-.. code-block:: python
+This is the ``uncertainties`` Python package, which performs **transparent
+calculations with uncertainties** (aka "error propagation"):
 
     >>> from uncertainties import ufloat
-
-    >>> x = ufloat(2, 0.25)
-    >>> x
-    2.0+/-0.25
-
-    >>> square = x**2  # Transparent calculations
-    >>> square
-    4.0+/-1.0
-    >>> square.nominal_value
-    4.0
-    >>> square.std_dev  # Standard deviation
-    1.0
-
-    >>> square - x*x
-    0.0  # Exactly 0: correlations taken into account
-
     >>> from uncertainties.umath import *  # sin(), etc.
-    >>> sin(1+x**2)
-    -0.95892427466313845+/-0.2836621854632263
-
-    >>> print (2*x+1000).derivatives[x]  # Automatic calculation of derivatives
-    2.0
-
-    >>> from uncertainties import unumpy  # Array manipulation
-    >>> random_vars = unumpy.uarray([1, 2], [0.1, 0.2])
-    >>> print random_vars
-    [1.0+/-0.1 2.0+/-0.2]
-    >>> print random_vars.mean()
-    1.50+/-0.11
-    >>> print unumpy.cos(random_vars)
-    [0.540302305868+/-0.0841470984808 -0.416146836547+/-0.181859485365]
-
-Main features
--------------
+    >>> x = ufloat(1, 0.1)  # x = 1+/-0.1
+    >>> print(2*x)
+    2.00+/-0.20
+    >>> sin(2*x)  # In a Python shell, "print" is optional
+    0.9092974268256817+/-0.08322936730942848
 
-- **Transparent calculations with uncertainties**: **no or little
-  modification of existing code** is needed.  Similarly, the Python_ (or
-  IPython_) shell can be used as **a powerful calculator** that
-  handles quantities with uncertainties (``print`` statements are
-  optional, which is convenient).
-
-- **Correlations** between expressions are correctly taken into
-  account.  Thus, ``x-x`` is exactly zero, for instance (most
-  implementations found on the web yield a non-zero uncertainty for
-  ``x-x``, which is incorrect).
-
-- **Almost all mathematical operations** are supported, including most
-  functions from the standard math_ module (sin,...).  Comparison
-  operators (``>``, ``==``, etc.) are supported too.
-
-- Many **fast operations on arrays and matrices** of numbers with
-  uncertainties are supported.
-
-- **Extensive support for printing** numbers with uncertainties
-  (including LaTeX support and pretty-printing).
-
-- Most uncertainty calculations are performed **analytically**.
-
-- This module also gives access to the **derivatives** of any
-  mathematical expression (they are used by `error
-  propagation theory`_, and are thus automatically calculated by this
-  module).
-
-
-Installation or upgrade
------------------------
-
-Installation instructions are available on the `main web site
-<http://uncertainties-python-package.readthedocs.io/en/latest/index.html#installation-and-download>`_
-for this package.
+This package also **automatically calculates derivatives of arbitrary functions**:
 
+    >>> (2*x+1000).derivatives[x]
+    2.0
 
+The main documentation is available at
+https://uncertainties.readthedocs.io/.
 
 Git branches
 ------------
 
 The ``release`` branch is the latest stable release. It should pass the tests.
 
+
 ``master*`` branches in the Github repository are bleeding-edge, and do not
 necessarily pass the tests. The ``master`` branch is the latest, relatively
 stable versions (while other ``master*`` branches are more experimental).
@@ -137,9 +67,3 @@ History
 This package was created back around 2009 by `Eric O. LEBIGOT <https://github.com/lebigot>`_.
 
 Ownership of the package was taken over by the `lmfit GitHub organization <https://github.com/lmfit>`_ in 2024.
-
-.. _Python: http://docs.python.org/tutorial/interpreter.html
-.. _IPython: http://ipython.readthedocs.io/en/stable/
-.. _math: http://docs.python.org/library/math.html
-.. _error propagation theory: http://en.wikipedia.org/wiki/Propagation_of_uncertainty
-.. _main website: http://uncertainties-python-package.readthedocs.io/