Allow zero values for mu and sigma (#60)

* Allow setting mu and sigma to 0

* Make doctests pass

* Add changelog fragment

Author: vivekjoshy

CODE_OF_CONDUCT.md

@@ -59,13 +59,13 @@ If a community member engages in unacceptable behavior, the community organizers
 
 If you are subject to or witness unacceptable behavior, or have any other concerns, please notify a community organizer as soon as possible. taven@opendebates.net.
 
-[Reporting guidelines](https://hq.opendebates.net/w/grievances/)
+[Reporting guidelines](https://wiki.opendebates.net/en/grievances)
 
 Additionally, community organizers are available to help community members engage with local law enforcement or to otherwise help those experiencing unacceptable behavior feel safe. In the context of in-person events, organizers will also provide escorts as desired by the person experiencing distress.
 
 ## 8. Addressing Grievances
 
-If you feel you have been falsely or unfairly accused of violating this Code of Conduct, you should notify Open Debates Project with a concise description of your grievance. Your grievance will be handled in accordance with our existing governing policies. [Policy](https://hq.opendebates.net/w/grievances/)
+If you feel you have been falsely or unfairly accused of violating this Code of Conduct, you should notify Open Debates Project with a concise description of your grievance. Your grievance will be handled in accordance with our existing governing policies. [Policy](https://wiki.opendebates.net/en/grievances)
 
 We will investigate any claims made in the report thoroughly and sufficient evidence is required for us to take action. We will not disclose any information that is sensitive and may damage the reputation of any community members
 
@@ -81,7 +81,7 @@ taven@opendebates.net
 
 ## 11. License and attribution
 
-The Citizen Code of Conduct is distributed by [Stumptown Syndicate](http://stumptownsyndicate.org) under a [Creative Commons Attribution-ShareAlike license](http://creativecommons.org/licenses/by-sa/3.0/). 
+The Citizen Code of Conduct is distributed by [Stumptown Syndicate](http://stumptownsyndicate.org) under a [Creative Commons Attribution-ShareAlike license](http://creativecommons.org/licenses/by-sa/3.0/).
 
 Portions of text derived from the [Django Code of Conduct](https://www.djangoproject.com/conduct/) and the [Geek Feminism Anti-Harassment Policy](http://geekfeminism.wikia.com/wiki/Conference_anti-harassment/Policy).
 

README.md

@@ -20,7 +20,7 @@ pip install openskill
 >>> from openskill import Rating, rate
 >>> a1 = Rating()
 >>> a1
-Rating(mu=25, sigma=8.333333333333334)
+Rating(mu=25.0, sigma=8.333333333333334)
 >>> a2 = Rating(mu=32.444, sigma=5.123)
 >>> a2
 Rating(mu=32.444, sigma=5.123)

changes/60.bugfix.rst

@@ -0,0 +1 @@
+Allow setting ``mu`` and ``sigma`` to 0 for ``Rating`` objects.

docs/manual.rst

@@ -13,7 +13,7 @@ Usage
    >>> from openskill import Rating, rate
    >>> a1 = Rating()
    >>> a1
-   Rating(mu=25, sigma=8.333333333333334)
+   Rating(mu=25.0, sigma=8.333333333333334)
    >>> a2 = Rating(mu=32.444, sigma=5.123)
    >>> a2
    Rating(mu=32.444, sigma=5.123)

openskill/constants.py

@@ -2,14 +2,14 @@ def z(**options) -> float:
     if "z" in options:
         return options["z"]
     else:
-        return 3
+        return 3.0
 
 
 def mu(**options) -> float:
     if "mu" in options:
         return options["mu"]
     else:
-        return 25
+        return 25.0
 
 
 def sigma(**options) -> float:

openskill/rate.py

@@ -25,8 +25,15 @@ def __init__(
         self, mu: Optional[float] = None, sigma: Optional[float] = None, **options
     ):
         # Calculate Mu and Sigma
-        self.mu = mu if mu else default_mu(**options)
-        self.sigma = sigma if sigma else default_sigma(**options)
+        if isinstance(mu, (float, int)):
+            self.mu = mu
+        else:
+            self.mu = default_mu(**options)
+
+        if isinstance(sigma, (float, int)):
+            self.sigma = sigma
+        else:
+            self.sigma = default_sigma(**options)
 
     def __repr__(self):
         return f"Rating(mu={self.mu}, sigma={self.sigma})"

setup.cfg

@@ -5,7 +5,7 @@ description = A faster, open-license alternative to Microsoft TrueSkill
 author = Taven <taven@outlook.in>
 author_email = contact@taven.me
 license = mit
-license_file = LICENSE
+license_files = LICENSE
 url = https://github.com/OpenDebates/openskill.py
 long_description = file: README.md
 long_description_content_type = text/markdown; charset=UTF-8