title: Django - Exception Type: NoReverseMatch
body: <p>hi guys im learning django but im getting this error and i dont know how to fix it, can you help me please? python 3.x /  django 1.9</p>
  
  <p>im getting this error:</p>
  
  <pre><code>NoReverseMatch at /
  Reverse for 'categoria' with arguments '(1,)' and keyword arguments '{}' not found. 0 pattern(s) tried: []
  Request Method: GET
  Request URL:    http://127.0.0.1:8000/
  Django Version: 1.9.1
  Exception Type: NoReverseMatch
  Exception Value:    
  Reverse for 'categoria' with arguments '(1,)' and keyword arguments '{}' not found. 0 pattern(s) tried: []
  Exception Location: C:\Users\Yiyeh\AppData\Local\Programs\Python\Python35-32\lib\site-packages\django\core\urlresolvers.py in _reverse_with_prefix, line 508
  Python Executable:  C:\Users\Yiyeh\AppData\Local\Programs\Python\Python35-32\python.exe
  Python Version: 3.5.1
  Python Path:    
  ['C:\\Users\\Yiyeh\\Documents\\Ejercicios\\Python\\puls\\puls',
   'C:\\Users\\Yiyeh\\AppData\\Local\\Programs\\Python\\Python35-32\\python35.zip',
   'C:\\Users\\Yiyeh\\AppData\\Local\\Programs\\Python\\Python35-32\\DLLs',
   'C:\\Users\\Yiyeh\\AppData\\Local\\Programs\\Python\\Python35-32\\lib',
   'C:\\Users\\Yiyeh\\AppData\\Local\\Programs\\Python\\Python35-32',
   'C:\\Users\\Yiyeh\\AppData\\Local\\Programs\\Python\\Python35-32\\lib\\site-packages']
  Server time:    Wed, 27 Jan 2016 17:52:56 -0300
  
  from django.shortcuts import render_to_response
  from django.http import HttpResponse
  from django.template.loader import get_template
  from django.template import Context
  from datetime import datetime
  from app.models import *
  </code></pre>
  
  <p>this is my view.py</p>
  
  <pre><code>def home(request):
      categorias = Categoria.objects.all()
      enlaces = Enlace.objects.all()
      template = "index.html"
      #diccionario = {"categorias": categorias,"enlaces":enlaces}
      return render_to_response(template,locals())
  </code></pre>
  
  <p>urls.py</p>
  
  <pre><code>from django.conf.urls import url
  from django.contrib import admin
  
  urlpatterns = [
      url(r'^admin/', admin.site.urls),
      url(r'^$', 'app.views.home', name='home'),
  ]
  </code></pre>
  
  <p>and index.html ( error on line 30 )</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html lang="es"&gt;
  &lt;head&gt;
      &lt;meta charset="utf-8" /&gt;
  
      &lt;meta name="viewport" 
            content="width=device-width, initial-scale=1, maximum-scale=1" /&gt;
  
      &lt;title&gt;Puls3: Comunidad online de gente pro y (no sé que más escribir)&lt;/title&gt;
      &lt;link rel="stylesheet" href="normalize.css" /&gt;
      &lt;link href='http://fonts.googleapis.com/css?family=PT+Sans:400,700,400italic,700italic' rel='stylesheet' type='text/css' /&gt;
      &lt;link rel="stylesheet" href="/static/estilos.css" /&gt;
      &lt;link rel="stylesheet" href="/static/responsive.css" /&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;!-- comentario de lo que sea --&gt;
      &lt;header&gt;
          &lt;figure id="logo"&gt;
              &lt;img src="logo.png" /&gt;
          &lt;/figure&gt;
          &lt;h1 id="titulo_header"&gt;Puls3: Comunidad de gente cool, atractiva y millonaria&lt;/h1&gt;
          &lt;figure id="avatar"&gt;
              &lt;img src="avatar.jpg" /&gt;
              &lt;figcaption&gt;&lt;/figcaption&gt;
          &lt;/figure&gt;
      &lt;/header&gt;
      &lt;nav&gt;
          &lt;ul&gt;
              &lt;li id="flechita_nav"&gt;&lt;a href="/"&gt;&lt;/a&gt;&lt;/li&gt;
              {% for cat in categorias %}
                  &lt;li&gt;&lt;a href="{% url "categoria" cat.pk %}"&gt;{{cat}}&lt;/a&gt;&lt;/li&gt;
              {% endfor %}
              &lt;li id="publicar_nav"&gt;&lt;a href="{% url "add" %}"&gt;Publicar&lt;/a&gt;&lt;/li&gt;
          &lt;/ul&gt;
      &lt;/nav&gt;
      &lt;aside id="bienvenida"&gt;
          {% if not request.user.is_authenticated %}
          &lt;h2&gt;Hola, registrate!&lt;/h2&gt;
          &lt;p&gt;Es importante registrarte porque LOL!&lt;/p&gt;
          &lt;a id="registro" href="#"&gt;Registrate acá&lt;/a&gt;
          &lt;p id="mensaje_registro"&gt;En serio, registrate por favor&lt;/p&gt;
          {% endif %}
      &lt;/aside&gt;
      &lt;section id="contenido"&gt;
          {% if enlaces %}
  
          {% for enlace in enlaces %}
          &lt;article class="item"&gt;
              &lt;figure class="imagen_item"&gt;
                  &lt;img src="imagen.jpg" /&gt;
              &lt;/figure&gt;
              &lt;h2 class="titulo_item"&gt;
                  &lt;a href="{{enlace.enlace}}"&gt;{{enlace.titulo}}&lt;/a&gt;
              &lt;/h2&gt;
              &lt;p class="autor_item"&gt;
                  Por &lt;a href="#"&gt;{{enlace.usuario}}&lt;/a&gt;
              &lt;/p&gt;
              &lt;p class="datos_item"&gt;
                  &lt;a class="tag_item" href="#"&gt;{{enlace.categoria}}&lt;/a&gt;
                  &lt;span class="fecha_item"&gt;Hace &lt;strong&gt;{{enlace.timestamp|timesince}}&lt;/strong&gt; min&lt;/span&gt;
                  &lt;a class="guardar_item" href="#"&gt;&lt;/a&gt;
              &lt;/p&gt;
              &lt;p class="votacion"&gt;
                  &lt;a class="up" href="{% url "plus" enlace.pk %}"&gt;&lt;/a&gt;
                  {{enlace.votos}}
                  &lt;a class="down" href="{% url "minus" enlace.pk %}"&gt;&lt;/a&gt;
              &lt;/p&gt;
          &lt;/article&gt;
          {% endfor %}
          {% else %}
              NO HAY ENLACES GUARDADOS
          {% endif %}
      &lt;/section&gt;
      &lt;footer&gt;
          &lt;p&gt;&lt;strong&gt;Powered by Platzi!&lt;/strong&gt;&lt;/p&gt;
          &lt;p&gt;Mejorando.la 2013 ®&lt;/p&gt;
      &lt;/footer&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>