├── .gitignore ├── CONTRIB.md ├── LICENSE ├── README.md ├── app.yaml ├── favicon.ico ├── index.html ├── main.py └── zombie_apocalypse.py /.gitignore: -------------------------------------------------------------------------------- 1 | *.py[cod] 2 | 3 | # C extensions 4 | *.so 5 | 6 | # Packages 7 | *.egg 8 | *.egg-info 9 | dist 10 | build 11 | eggs 12 | parts 13 | bin 14 | var 15 | sdist 16 | develop-eggs 17 | .installed.cfg 18 | lib 19 | lib64 20 | 21 | # Installer logs 22 | pip-log.txt 23 | 24 | # Unit test / coverage reports 25 | .coverage 26 | .tox 27 | nosetests.xml 28 | 29 | # Translations 30 | *.mo 31 | 32 | # Mr Developer 33 | .mr.developer.cfg 34 | .project 35 | .pydevproject 36 | -------------------------------------------------------------------------------- /CONTRIB.md: -------------------------------------------------------------------------------- 1 | # How to become a contributor and submit your own code 2 | 3 | ## Contributor License Agreements 4 | 5 | We'd love to accept your sample apps and patches! Before we can take them, we 6 | have to jump a couple of legal hurdles. 7 | 8 | Please fill out either the individual or corporate Contributor License Agreement 9 | (CLA). 10 | 11 | * If you are an individual writing original source code and you're sure you 12 | own the intellectual property, then you'll need to sign an [individual CLA] 13 | (https://developers.google.com/open-source/cla/individual). 14 | * If you work for a company that wants to allow you to contribute your work, 15 | then you'll need to sign a [corporate CLA] 16 | (https://developers.google.com/open-source/cla/corporate). 17 | 18 | Follow either of the two links above to access the appropriate CLA and 19 | instructions for how to sign and return it. Once we receive it, we'll be able to 20 | accept your pull requests. 21 | 22 | ## Contributing A Patch 23 | 24 | 1. Submit an issue describing your proposed change to the repo in question. 25 | 1. The repo owner will respond to your issue promptly. 26 | 1. If your proposed change is accepted, and you haven't already done so, sign a 27 | Contributor License Agreement (see details above). 28 | 1. Fork the desired repo, develop and test your code changes. 29 | 1. Ensure that your code adheres to the existing style in the sample to which 30 | you are contributing. Refer to the 31 | [Google Cloud Platform Samples Style Guide] 32 | (https://github.com/GoogleCloudPlatform/Template/wiki/style.html) for the 33 | recommended coding standards for this organization. 34 | 1. Ensure that your code has an appropriate set of unit tests which all pass. 35 | 1. Submit a pull request. 36 | 37 | ## Contributing A New Sample App 38 | 39 | 1. Submit an issue to the GoogleCloudPlatform/Template repo describing your 40 | proposed sample app. 41 | 1. The Template repo owner will respond to your enhancement issue promptly. 42 | Instructional value is the top priority when evaluating new app proposals for 43 | this collection of repos. 44 | 1. If your proposal is accepted, and you haven't already done so, sign a 45 | Contributor License Agreement (see details above). 46 | 1. Create your own repo for your app following this naming convention: 47 | * {product}-{app-name}-{language} 48 | * products: appengine, compute, storage, bigquery, prediction, cloudsql 49 | * example: appengine-guestbook-python 50 | * For multi-product apps, concatenate the primary products, like this: 51 | compute-appengine-demo-suite-python. 52 | * For multi-language apps, concatenate the primary languages like this: 53 | appengine-sockets-python-java-go. 54 | 55 | 1. Clone the README.md, CONTRIB.md and LICENSE files from the 56 | GoogleCloudPlatform/Template repo. 57 | 1. Ensure that your code adheres to the existing style in the sample to which 58 | you are contributing. Refer to the 59 | [Google Cloud Platform Samples Style Guide] 60 | (https://github.com/GoogleCloudPlatform/Template/wiki/style.html) for the 61 | recommended coding standards for this organization. 62 | 1. Ensure that your code has an appropriate set of unit tests which all pass. 63 | 1. Submit a request to fork your repo in GoogleCloudPlatform organizationt via 64 | your proposal issue. 65 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. Definitions. 8 | 9 | "License" shall mean the terms and conditions for use, reproduction, 10 | and distribution as defined by Sections 1 through 9 of this document. 11 | 12 | "Licensor" shall mean the copyright owner or entity authorized by 13 | the copyright owner that is granting the License. 14 | 15 | "Legal Entity" shall mean the union of the acting entity and all 16 | other entities that control, are controlled by, or are under common 17 | control with that entity. For the purposes of this definition, 18 | "control" means (i) the power, direct or indirect, to cause the 19 | direction or management of such entity, whether by contract or 20 | otherwise, or (ii) ownership of fifty percent (50%) or more of the 21 | outstanding shares, or (iii) beneficial ownership of such entity. 22 | 23 | "You" (or "Your") shall mean an individual or Legal Entity 24 | exercising permissions granted by this License. 25 | 26 | "Source" form shall mean the preferred form for making modifications, 27 | including but not limited to software source code, documentation 28 | source, and configuration files. 29 | 30 | "Object" form shall mean any form resulting from mechanical 31 | transformation or translation of a Source form, including but 32 | not limited to compiled object code, generated documentation, 33 | and conversions to other media types. 34 | 35 | "Work" shall mean the work of authorship, whether in Source or 36 | Object form, made available under the License, as indicated by a 37 | copyright notice that is included in or attached to the work 38 | (an example is provided in the Appendix below). 39 | 40 | "Derivative Works" shall mean any work, whether in Source or Object 41 | form, that is based on (or derived from) the Work and for which the 42 | editorial revisions, annotations, elaborations, or other modifications 43 | represent, as a whole, an original work of authorship. For the purposes 44 | of this License, Derivative Works shall not include works that remain 45 | separable from, or merely link (or bind by name) to the interfaces of, 46 | the Work and Derivative Works thereof. 47 | 48 | "Contribution" shall mean any work of authorship, including 49 | the original version of the Work and any modifications or additions 50 | to that Work or Derivative Works thereof, that is intentionally 51 | submitted to Licensor for inclusion in the Work by the copyright owner 52 | or by an individual or Legal Entity authorized to submit on behalf of 53 | the copyright owner. For the purposes of this definition, "submitted" 54 | means any form of electronic, verbal, or written communication sent 55 | to the Licensor or its representatives, including but not limited to 56 | communication on electronic mailing lists, source code control systems, 57 | and issue tracking systems that are managed by, or on behalf of, the 58 | Licensor for the purpose of discussing and improving the Work, but 59 | excluding communication that is conspicuously marked or otherwise 60 | designated in writing by the copyright owner as "Not a Contribution." 61 | 62 | "Contributor" shall mean Licensor and any individual or Legal Entity 63 | on behalf of whom a Contribution has been received by Licensor and 64 | subsequently incorporated within the Work. 65 | 66 | 2. Grant of Copyright License. Subject to the terms and conditions of 67 | this License, each Contributor hereby grants to You a perpetual, 68 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 69 | copyright license to reproduce, prepare Derivative Works of, 70 | publicly display, publicly perform, sublicense, and distribute the 71 | Work and such Derivative Works in Source or Object form. 72 | 73 | 3. Grant of Patent License. Subject to the terms and conditions of 74 | this License, each Contributor hereby grants to You a perpetual, 75 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 76 | (except as stated in this section) patent license to make, have made, 77 | use, offer to sell, sell, import, and otherwise transfer the Work, 78 | where such license applies only to those patent claims licensable 79 | by such Contributor that are necessarily infringed by their 80 | Contribution(s) alone or by combination of their Contribution(s) 81 | with the Work to which such Contribution(s) was submitted. If You 82 | institute patent litigation against any entity (including a 83 | cross-claim or counterclaim in a lawsuit) alleging that the Work 84 | or a Contribution incorporated within the Work constitutes direct 85 | or contributory patent infringement, then any patent licenses 86 | granted to You under this License for that Work shall terminate 87 | as of the date such litigation is filed. 88 | 89 | 4. Redistribution. You may reproduce and distribute copies of the 90 | Work or Derivative Works thereof in any medium, with or without 91 | modifications, and in Source or Object form, provided that You 92 | meet the following conditions: 93 | 94 | (a) You must give any other recipients of the Work or 95 | Derivative Works a copy of this License; and 96 | 97 | (b) You must cause any modified files to carry prominent notices 98 | stating that You changed the files; and 99 | 100 | (c) You must retain, in the Source form of any Derivative Works 101 | that You distribute, all copyright, patent, trademark, and 102 | attribution notices from the Source form of the Work, 103 | excluding those notices that do not pertain to any part of 104 | the Derivative Works; and 105 | 106 | (d) If the Work includes a "NOTICE" text file as part of its 107 | distribution, then any Derivative Works that You distribute must 108 | include a readable copy of the attribution notices contained 109 | within such NOTICE file, excluding those notices that do not 110 | pertain to any part of the Derivative Works, in at least one 111 | of the following places: within a NOTICE text file distributed 112 | as part of the Derivative Works; within the Source form or 113 | documentation, if provided along with the Derivative Works; or, 114 | within a display generated by the Derivative Works, if and 115 | wherever such third-party notices normally appear. The contents 116 | of the NOTICE file are for informational purposes only and 117 | do not modify the License. You may add Your own attribution 118 | notices within Derivative Works that You distribute, alongside 119 | or as an addendum to the NOTICE text from the Work, provided 120 | that such additional attribution notices cannot be construed 121 | as modifying the License. 122 | 123 | You may add Your own copyright statement to Your modifications and 124 | may provide additional or different license terms and conditions 125 | for use, reproduction, or distribution of Your modifications, or 126 | for any such Derivative Works as a whole, provided Your use, 127 | reproduction, and distribution of the Work otherwise complies with 128 | the conditions stated in this License. 129 | 130 | 5. Submission of Contributions. Unless You explicitly state otherwise, 131 | any Contribution intentionally submitted for inclusion in the Work 132 | by You to the Licensor shall be under the terms and conditions of 133 | this License, without any additional terms or conditions. 134 | Notwithstanding the above, nothing herein shall supersede or modify 135 | the terms of any separate license agreement you may have executed 136 | with Licensor regarding such Contributions. 137 | 138 | 6. Trademarks. This License does not grant permission to use the trade 139 | names, trademarks, service marks, or product names of the Licensor, 140 | except as required for reasonable and customary use in describing the 141 | origin of the Work and reproducing the content of the NOTICE file. 142 | 143 | 7. Disclaimer of Warranty. Unless required by applicable law or 144 | agreed to in writing, Licensor provides the Work (and each 145 | Contributor provides its Contributions) on an "AS IS" BASIS, 146 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 147 | implied, including, without limitation, any warranties or conditions 148 | of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A 149 | PARTICULAR PURPOSE. You are solely responsible for determining the 150 | appropriateness of using or redistributing the Work and assume any 151 | risks associated with Your exercise of permissions under this License. 152 | 153 | 8. Limitation of Liability. In no event and under no legal theory, 154 | whether in tort (including negligence), contract, or otherwise, 155 | unless required by applicable law (such as deliberate and grossly 156 | negligent acts) or agreed to in writing, shall any Contributor be 157 | liable to You for damages, including any direct, indirect, special, 158 | incidental, or consequential damages of any character arising as a 159 | result of this License or out of the use or inability to use the 160 | Work (including but not limited to damages for loss of goodwill, 161 | work stoppage, computer failure or malfunction, or any and all 162 | other commercial damages or losses), even if such Contributor 163 | has been advised of the possibility of such damages. 164 | 165 | 9. Accepting Warranty or Additional Liability. While redistributing 166 | the Work or Derivative Works thereof, You may choose to offer, 167 | and charge a fee for, acceptance of support, warranty, indemnity, 168 | or other liability obligations and/or rights consistent with this 169 | License. However, in accepting such obligations, You may act only 170 | on Your own behalf and on Your sole responsibility, not on behalf 171 | of any other Contributor, and only if You agree to indemnify, 172 | defend, and hold each Contributor harmless for any liability 173 | incurred by, or claims asserted against, such Contributor by reason 174 | of your accepting any such warranty or additional liability. 175 | 176 | END OF TERMS AND CONDITIONS 177 | 178 | APPENDIX: How to apply the Apache License to your work. 179 | 180 | To apply the Apache License to your work, attach the following 181 | boilerplate notice, with the fields enclosed by brackets "[]" 182 | replaced with your own identifying information. (Don't include 183 | the brackets!) The text should be enclosed in the appropriate 184 | comment syntax for the file format. We also recommend that a 185 | file or class name and description of purpose be included on the 186 | same "printed page" as the copyright notice for easier 187 | identification within third-party archives. 188 | 189 | Copyright 2013 Google Inc. 190 | 191 | Licensed under the Apache License, Version 2.0 (the "License"); 192 | you may not use this file except in compliance with the License. 193 | You may obtain a copy of the License at 194 | 195 | http://www.apache.org/licenses/LICENSE-2.0 196 | 197 | Unless required by applicable law or agreed to in writing, software 198 | distributed under the License is distributed on an "AS IS" BASIS, 199 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 200 | See the License for the specific language governing permissions and 201 | limitations under the License. 202 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | Copyright (C) 2010-2014 Google Inc. 2 | # App Engine Python VM Runtime 'Zombie Apocalypse' example 3 | 4 | This sample is inspired by a [Zombie Apocalypse ODEINT demo][1] listed 5 | in the [Scipy Cookbook][2]. 6 | 7 | It demos use of the `apt_get_install` directive in the `app.yaml` file to load `python-numpy`, `python-scipy`, and `python-matplotlib`. 8 | 9 | ## Deploying 10 | 11 | 1. Make sure that you are invited to the [VM Runtime Trusted Tester 12 | Program][3], and [download the SDK](http://commondatastorage.googleapis.com/gae-vm-runtime-tt/vmruntime_sdks.html). 13 | 2. Update the `application` value of the `app.yaml` file from 14 | `your-app-id` to the Application ID which is whitelisted for the VM 15 | Runtime Trusted Tester Program. 16 | 3. Run the following command: 17 | 18 | ``` 19 | $ /appcfg.py -s preview.appengine.google.com update 20 | ``` 21 | 22 | 4. Visit the following URL: 23 | `http://your-app-id.appspot.com/` 24 | 25 | 26 | ## Contributing changes 27 | 28 | * See [CONTRIB.md](CONTRIB.md) 29 | 30 | 31 | ## Licensing 32 | 33 | * See [LICENSE](LICENSE) 34 | 35 | 36 | [1]: http://wiki.scipy.org/Cookbook/Zombie_Apocalypse_ODEINT 37 | [2]: http://wiki.scipy.org/Cookbook/ 38 | [3]: https://docs.google.com/document/d/1VH1oVarfKILAF_TfvETtPPE3TFzIuWqsa22PtkRkgJ4 39 | [4]: https://developers.google.com/compute/docs/gcutil/ 40 | [5]: https://cloud.google.com/console 41 | -------------------------------------------------------------------------------- /app.yaml: -------------------------------------------------------------------------------- 1 | runtime: python27 2 | api_version: 1 3 | threadsafe: true 4 | vm: true 5 | 6 | vm_settings: 7 | apt_get_install: python-numpy python-scipy python-matplotlib 8 | 9 | handlers: 10 | 11 | # Favicon. Without this, the browser hits this once per page view. 12 | - url: /favicon.ico 13 | static_files: favicon.ico 14 | upload: favicon.ico 15 | 16 | # Main app. All the real work is here. 17 | - url: /.* 18 | script: main.APPLICATION 19 | -------------------------------------------------------------------------------- /favicon.ico: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/GoogleCloudPlatform/appengine-scipy-zombie-apocalypse-python/4bb47ffee6ea2ad325ccc9ea6da5f835938d730f/favicon.ico -------------------------------------------------------------------------------- /index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 9 | 15 | 16 | 17 | 18 |
19 |
20 | 21 | Initial population: 22 | {{ initial_population }} 23 |
24 | 28 |
29 | 30 | Initial dead: 31 | {{ initial_death_population }} 32 |
33 | 37 |
38 | 39 | Birth rate: 40 | {{ birth_rate }} 41 |
42 | 46 |
47 | 48 | Transmission percent: 49 | {{ transmission_percent }} 50 |
51 | 55 | 56 |
57 | Reset 58 |
59 | 60 |
61 |

Zombie Apocalypse:
62 | 63 |

64 | 65 | 66 | -------------------------------------------------------------------------------- /main.py: -------------------------------------------------------------------------------- 1 | """A Zombie Apocalypse simulator sample with scipy library.""" 2 | 3 | import multiprocessing 4 | import os 5 | import StringIO 6 | import urllib 7 | 8 | import jinja2 9 | import webapp2 10 | 11 | import zombie_apocalypse 12 | 13 | 14 | JINJA_ENVIRONMENT = jinja2.Environment( 15 | loader=jinja2.FileSystemLoader(os.path.dirname(__file__)), 16 | extensions=['jinja2.ext.autoescape']) 17 | 18 | 19 | def simulate(conn, params): 20 | """Creates a simulation object and generates a resulted png files. 21 | 22 | Then sends the contents of the png file to the parent process. 23 | 24 | Args: 25 | conn: A pipe object to interact with the parent process. 26 | params: A dictionary for the simulator constructor. 27 | """ 28 | simulator = zombie_apocalypse.ZombieApocalypseSimulator(**params) 29 | image_buffer = StringIO.StringIO() 30 | simulator.plot(image_buffer) 31 | conn.send(image_buffer.getvalue()) 32 | conn.close() 33 | 34 | 35 | def parse_params(request): 36 | """Parses the WebOb request object and returns a dictionary. 37 | 38 | Args: 39 | request: a WebOb request object. 40 | 41 | Returns: 42 | A dict contains values extracted from the request, or the 43 | default values if not specfied. 44 | """ 45 | initial_population = float(request.get( 46 | 'initial_population', 47 | zombie_apocalypse.DEFAULT_INITIAL_POPULATION)) 48 | initial_death_population = float(request.get( 49 | 'initial_death_population', 50 | zombie_apocalypse.DEFAULT_INITIAL_DEATH_POPULATION)) 51 | birth_rate = float(request.get( 52 | 'birth_rate', 53 | zombie_apocalypse.DEFAULT_BIRTH_RATE)) 54 | transmission_percent = float(request.get( 55 | 'transmission_percent', 56 | zombie_apocalypse.DEFAULT_TRANSMISSION_PERCENT)) 57 | return { 58 | 'initial_population': initial_population, 59 | 'initial_death_population': initial_death_population, 60 | 'birth_rate': birth_rate, 61 | 'transmission_percent': transmission_percent, 62 | } 63 | 64 | 65 | class MainPage(webapp2.RequestHandler): 66 | """A handler for showing the simulator form.""" 67 | 68 | def get(self): 69 | """Shows some controllers and an image tag. """ 70 | params = parse_params(self.request) 71 | template = JINJA_ENVIRONMENT.get_template('index.html') 72 | 73 | image_url = '/draw_simulation?{}'.format(urllib.urlencode(params)) 74 | params['image_url'] = image_url 75 | self.response.write(template.render(params)) 76 | 77 | 78 | class SimulationImage(webapp2.RequestHandler): 79 | """A handler for returning a graph showing the simulation result.""" 80 | 81 | def get(self): 82 | """Shows a png graph showing the simulation result. 83 | 84 | We use a child process for generating the png file because the 85 | matplotlib.pyplot is not threadsafe. 86 | """ 87 | params = parse_params(self.request) 88 | parent_conn, child_conn = multiprocessing.Pipe() 89 | process = multiprocessing.Process(target=simulate, 90 | args=(child_conn, params)) 91 | process.start() 92 | self.response.headers['content-type'] = 'image/png' 93 | self.response.write(parent_conn.recv()) 94 | process.join() 95 | 96 | 97 | APPLICATION = webapp2.WSGIApplication([ 98 | ('/', MainPage), 99 | ('/draw_simulation.*', SimulationImage), 100 | ], debug=True) 101 | -------------------------------------------------------------------------------- /zombie_apocalypse.py: -------------------------------------------------------------------------------- 1 | """A simulator for Zombie Apocalypse. 2 | 3 | (see Munz et al. 2009) 4 | http://mysite.science.uottawa.ca/rsmith43/Zombies.pdf 5 | """ 6 | 7 | import os 8 | 9 | # Set this before import matplotlib 10 | os.environ['MPLCONFIGDIR'] = '/tmp' 11 | 12 | # This is needed before importing pyplot for rendering the image 13 | import matplotlib 14 | matplotlib.use('Agg') 15 | 16 | import numpy 17 | from matplotlib import pyplot 18 | from scipy.integrate import odeint 19 | 20 | 21 | DEFAULT_TIME_VECTOR = numpy.linspace(0, 5., 1000) 22 | DEFAULT_INITIAL_POPULATION = 500. 23 | DEFAULT_INITIAL_ZOMBIE_POPULATION = 0. 24 | DEFAULT_INITIAL_DEATH_POPULATION = 0. 25 | DEFAULT_BIRTH_RATE = 0. # birth rate 26 | DEFAULT_NATURAL_DEATH_PERCENT = 0.01 # natural death percent (per day) 27 | DEFAULT_TRANSMISSION_PERCENT = 0.95 # transmission percent (per day) 28 | DEFAULT_RESURRECT_PERCENT = 0.01 # resurrect percent (per day) 29 | DEFAULT_DESTROY_PERCENT = 0.01 # destroy percent (per day) 30 | PLOT_TITLE_TEMPLATE = """\ 31 | init po: {}, init zombie: {}, init death: {}, {} daily birth 32 | death pct. {}%, trans pct. {}%, resur pct. {}%, destroy pct. {}%.""" 33 | 34 | 35 | class ZombieApocalypseSimulator(object): 36 | """A simulator for Zombie Apocalypse (see Munz et al. 2009).""" 37 | 38 | def __init__(self, 39 | time_vector=DEFAULT_TIME_VECTOR, 40 | initial_population=DEFAULT_INITIAL_POPULATION, 41 | initial_zombie_population=DEFAULT_INITIAL_ZOMBIE_POPULATION, 42 | initial_death_population=DEFAULT_INITIAL_DEATH_POPULATION, 43 | birth_rate=DEFAULT_BIRTH_RATE, 44 | natural_death_percent=DEFAULT_NATURAL_DEATH_PERCENT, 45 | transmission_percent=DEFAULT_TRANSMISSION_PERCENT, 46 | resurrect_percent=DEFAULT_RESURRECT_PERCENT, 47 | destroy_percent=DEFAULT_DESTROY_PERCENT): 48 | """A constructor for the simulator. 49 | 50 | Args: 51 | time_vector: A time span for the simulation. 52 | initial_population: Initial population of the human beings. 53 | initial_zombie_population: Initial population of the Zombies. 54 | initial_death_population: Initial number of the dead bodies. 55 | birth_rate: Number of births/day. 56 | natural_death_percent: Natural death percent per day. 57 | transmission_percent: Transmission percent per day 58 | (a human becomes a zombie). 59 | resurrect_percent: Resurrection percent per day 60 | (a dead body becomes a zombie). 61 | destroy_percent: Destroy percent per day 62 | (a zombie is completely destroyed). 63 | """ 64 | self.time_vector = time_vector 65 | self.initial_population = initial_population 66 | self.initial_zombie_population = initial_zombie_population 67 | self.initial_death_population = initial_death_population 68 | self.birth_rate = birth_rate 69 | self.natural_death_rate = natural_death_percent / 100 70 | self.transmission_rate = transmission_percent / 100 71 | self.resurrect_rate = resurrect_percent / 100 72 | self.destroy_rate = destroy_percent / 100 73 | 74 | def _compute_populations(self, y, t): 75 | """Compute the populations at the given time point. 76 | 77 | Args: 78 | y: A list containing the numbers of human beings, zombies, 79 | and dead bodies. 80 | t: A time point for the computation. 81 | 82 | Returns: 83 | A list containing the numbers of human beings, zombies, 84 | and dead bodies for the given time point. 85 | """ 86 | Si = y[0] 87 | Zi = y[1] 88 | Ri = y[2] 89 | # the model equations (see Munz et al. 2009) 90 | f0 = (self.birth_rate - self.transmission_rate * Si * Zi 91 | - self.natural_death_rate * Si) 92 | f1 = (self.transmission_rate * Si * Zi 93 | + self.resurrect_rate * Ri 94 | - self.destroy_rate / 100 * Si * Zi) 95 | f2 = (self.natural_death_rate * Si + self.destroy_rate * Si * Zi 96 | - self.resurrect_rate * Ri) 97 | return [f0, f1, f2] 98 | 99 | def _solve(self): 100 | """Returns the simulated result.""" 101 | y0 = [self.initial_population, self.initial_zombie_population, 102 | self.initial_death_population] 103 | return odeint(self._compute_populations, y0, self.time_vector) 104 | 105 | @property 106 | def plot_title(self): 107 | """Creates a title string of the result image. 108 | 109 | Returns: 110 | A title string of the image. 111 | """ 112 | return PLOT_TITLE_TEMPLATE.format( 113 | self.initial_population, 114 | self.initial_zombie_population, 115 | self.initial_death_population, 116 | self.birth_rate, 117 | self.natural_death_rate*100.0, 118 | self.transmission_rate*100.0, 119 | self.resurrect_rate*100.0, 120 | self.destroy_rate*100.0) 121 | 122 | def plot(self, file_object): 123 | """Creates a png object and write it to the given object. 124 | 125 | Args: 126 | file_object: A file object for writing the binary data 127 | of the generated png file. 128 | """ 129 | soln = self._solve() 130 | S = soln[:, 0] 131 | Z = soln[:, 1] 132 | R = soln[:, 2] 133 | pyplot.figure() 134 | pyplot.plot(self.time_vector, S, label='Living') 135 | pyplot.plot(self.time_vector, Z, label='Zombies') 136 | pyplot.xlabel('Days from outbreak') 137 | pyplot.ylabel('Population') 138 | pyplot.title(self.plot_title) 139 | pyplot.legend(loc=0) 140 | pyplot.savefig(file_object, format='png') 141 | --------------------------------------------------------------------------------