├── calc ├── __init__.py ├── calculus │ ├── __init__.py │ ├── integral.py │ └── differential.py ├── basecalc.py └── algebra │ └── linear │ └── perimeter.py ├── tests └── __init__.py ├── README.md ├── setup.py ├── .gitignore └── LICENSE /calc/__init__.py: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /tests/__init__.py: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /calc/calculus/__init__.py: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /calc/basecalc.py: -------------------------------------------------------------------------------- 1 | # Simple calculator interface to be implemented by all calculators 2 | # author: Kaan Eraslan 3 | # license: see, LICENSE 4 | 5 | from abc import ABC, abstractmethod 6 | 7 | 8 | class Calculator(ABC): 9 | "A base class for all calculators" 10 | 11 | @abstractmethod 12 | def show_formula(self): 13 | raise NotImplementedError 14 | 15 | @abstractmethod 16 | def show_explanation(self): 17 | raise NotImplementedError 18 | 19 | @abstractmethod 20 | def result(self): 21 | raise NotImplementedError 22 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # calculaide 2 | Simple calculator for explaning math topics. 3 | 4 | # Description 5 | 6 | The goal is simple. Math topics are understood better 7 | when one sees the formula along with its implementation in a programming language. 8 | 9 | Each calculator is designed to give an explanation on the topic and the underlying 10 | formula used in the implementation. 11 | Explanations are mostly based on our math notes in [here](https://github.com/D-K-E/ai-notes). 12 | Once you see the formula and the explanation try implementing it on your own. 13 | A basic implementation is also provided whereever possible. 14 | -------------------------------------------------------------------------------- /setup.py: -------------------------------------------------------------------------------- 1 | import os 2 | import setuptools 3 | 4 | 5 | # currentdir = os.getcwd() 6 | 7 | with open("README.md", "r", encoding="utf-8") as f: 8 | long_desc = f.read() 9 | 10 | with open("LICENSE", "r", encoding="utf-8") as f: 11 | license_str = f.read() 12 | 13 | setuptools.setup( 14 | name="calculaide", 15 | version="0.1", 16 | author='Kaan Eraslan', 17 | python_requires='>=3.5.0', 18 | author_email="kaaneraslan@gmail.com", 19 | description="Simple calculator for explaning math topics.", 20 | long_description=long_desc, 21 | long_description_content_type="text/markdown", 22 | license=license_str, 23 | url="https://github.com/D-K-E/calculaide", 24 | packages=setuptools.find_packages( 25 | exclude=["tests", "*.tests", "*.tests.*", "tests.*", 26 | "docs", ".gitignore", "README.md"] 27 | ), 28 | test_suite="tests", 29 | install_requires=[ 30 | ], 31 | classifiers=[ 32 | "Programming Language :: Python :: 3", 33 | "License :: OSI Approved :: GPLv3 License", 34 | "Operating System :: OS Independent", 35 | ], 36 | ) 37 | -------------------------------------------------------------------------------- /calc/calculus/integral.py: -------------------------------------------------------------------------------- 1 | # Simple calculator for integrals intended for educative use 2 | # author: Kaan Eraslan 3 | # license: see, LICENSE 4 | 5 | import math 6 | 7 | from calc.basecalc import Calculator 8 | from typing import Callable, List 9 | import inspect 10 | 11 | 12 | class D1IntegralCalculator(Calculator): 13 | "1D integral calculator" 14 | 15 | def __init__(self, upper_bound, lower_bound, step): 16 | "" 17 | self.ub = upper_bound 18 | self.lb = lower_bound 19 | self.f = fn 20 | self.step = step 21 | self.exp = """ 22 | ========= 23 | Integrals 24 | ========= 25 | 26 | Integrals measure the area under the curve of a function that is 27 | differentiable. 28 | 29 | This means that: 30 | - We know the global behaviour of the function 31 | """ 32 | 33 | pass 34 | 35 | 36 | def main(): 37 | print("Welcome to simple differential calculator") 38 | param = input("Enter a floating number [Ex. 12.2, 42.1, etc]: ") 39 | param = float(param) 40 | print("Using 0.0001 as a step value") 41 | calc = D1DiffCalculator(param, 0.001) 42 | calc.result() 43 | 44 | 45 | if __name__ == "__main__": 46 | main() 47 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | # Byte-compiled / optimized / DLL files 2 | __pycache__/ 3 | *.py[cod] 4 | *$py.class 5 | 6 | # C extensions 7 | *.so 8 | 9 | # Distribution / packaging 10 | .Python 11 | build/ 12 | develop-eggs/ 13 | dist/ 14 | downloads/ 15 | eggs/ 16 | .eggs/ 17 | lib/ 18 | lib64/ 19 | parts/ 20 | sdist/ 21 | var/ 22 | wheels/ 23 | pip-wheel-metadata/ 24 | share/python-wheels/ 25 | *.egg-info/ 26 | .installed.cfg 27 | *.egg 28 | MANIFEST 29 | 30 | # PyInstaller 31 | # Usually these files are written by a python script from a template 32 | # before PyInstaller builds the exe, so as to inject date/other infos into it. 33 | *.manifest 34 | *.spec 35 | 36 | # Installer logs 37 | pip-log.txt 38 | pip-delete-this-directory.txt 39 | 40 | # Unit test / coverage reports 41 | htmlcov/ 42 | .tox/ 43 | .nox/ 44 | .coverage 45 | .coverage.* 46 | .cache 47 | nosetests.xml 48 | coverage.xml 49 | *.cover 50 | *.py,cover 51 | .hypothesis/ 52 | .pytest_cache/ 53 | 54 | # Translations 55 | *.mo 56 | *.pot 57 | 58 | # Django stuff: 59 | *.log 60 | local_settings.py 61 | db.sqlite3 62 | db.sqlite3-journal 63 | 64 | # Flask stuff: 65 | instance/ 66 | .webassets-cache 67 | 68 | # Scrapy stuff: 69 | .scrapy 70 | 71 | # Sphinx documentation 72 | docs/_build/ 73 | 74 | # PyBuilder 75 | target/ 76 | 77 | # Jupyter Notebook 78 | .ipynb_checkpoints 79 | 80 | # IPython 81 | profile_default/ 82 | ipython_config.py 83 | 84 | # pyenv 85 | .python-version 86 | 87 | # pipenv 88 | # According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control. 89 | # However, in case of collaboration, if having platform-specific dependencies or dependencies 90 | # having no cross-platform support, pipenv may install dependencies that don't work, or not 91 | # install all needed dependencies. 92 | #Pipfile.lock 93 | 94 | # PEP 582; used by e.g. github.com/David-OConnor/pyflow 95 | __pypackages__/ 96 | 97 | # Celery stuff 98 | celerybeat-schedule 99 | celerybeat.pid 100 | 101 | # SageMath parsed files 102 | *.sage.py 103 | 104 | # Environments 105 | .env 106 | .venv 107 | env/ 108 | venv/ 109 | ENV/ 110 | env.bak/ 111 | venv.bak/ 112 | 113 | # Spyder project settings 114 | .spyderproject 115 | .spyproject 116 | 117 | # Rope project settings 118 | .ropeproject 119 | 120 | # mkdocs documentation 121 | /site 122 | 123 | # mypy 124 | .mypy_cache/ 125 | .dmypy.json 126 | dmypy.json 127 | 128 | # Pyre type checker 129 | .pyre/ 130 | -------------------------------------------------------------------------------- /calc/algebra/linear/perimeter.py: -------------------------------------------------------------------------------- 1 | # Simple calculator for perimeters of different shapes intended for educative use 2 | # author: Kaan Eraslan 3 | # license: see, LICENSE 4 | 5 | from calc.basecalc import Calculator 6 | from typing import Callable, List 7 | import inspect 8 | 9 | 10 | class PerimeterCalculator(Calculator): 11 | def perimeter(self): 12 | raise NotImplementedError 13 | 14 | def show_formula(self): 15 | print(self.formula) 16 | 17 | def show_explanation(self): 18 | print(self.exp) 19 | 20 | def result(self): 21 | self.show_explanation() 22 | self.show_formula() 23 | print("\nHere is our implementation:\n") 24 | print(inspect.getsource(self.perimeter)) 25 | print("\nGives the following result:\n") 26 | print(str(self.perimeter())) 27 | 28 | 29 | class TrianglePerimCalculator(PerimeterCalculator): 30 | def __init__(self, sides: List[float]): 31 | self.side1 = sides[0] 32 | self.side2 = sides[1] 33 | self.side3 = sides[2] 34 | self.exp = """ 35 | ====================== 36 | Perimeter of Triangle 37 | ====================== 38 | 39 | A 40 | / \\ 41 | / \\ 42 | / \\ 43 | B-------C 44 | 45 | Basically the perimeter of triangle is |AB| + |AC| + |BC| 46 | """ 47 | self.formula = "|AB| + |BC| + |AC| = P_{triangle}" 48 | 49 | def perimeter(self): 50 | result = self.side1 + self.side2 + self.side3 51 | return result 52 | 53 | 54 | class SquarePerimeterCalculator(PerimeterCalculator): 55 | "Square perimeter calculator" 56 | 57 | def __init__(self, side: float): 58 | self.side = side 59 | self.exp = """ 60 | ====================== 61 | Perimeter of Square 62 | ====================== 63 | 64 | A-------D 65 | | | 66 | | | side 67 | | | 68 | B-------C 69 | side 70 | 71 | Perimeter of Square is |AB| + |BC| + |CD| + |DA| 72 | which can also be expressed as 4 * side 73 | """ 74 | self.formula = "4 * side" 75 | 76 | def perimeter(self): 77 | return 4 * self.side 78 | 79 | 80 | class RectanglePerimeterCalculator(PerimeterCalculator): 81 | "Rectangle perimeter calculator" 82 | 83 | def __init__(self, width: float, height: float): 84 | self.w = width 85 | self.h = height 86 | self.exp = """ 87 | ====================== 88 | Perimeter of Rectangle 89 | ====================== 90 | 91 | A------------D 92 | | | 93 | | | width 94 | | | 95 | B------------C 96 | height 97 | 98 | Perimeter of Rectangle is |AB| + |BC| + |CD| + |DA| 99 | which can also be expressed as 2 * width + 2 * height 100 | """ 101 | self.formula = "2 * width + 2 * height" 102 | 103 | def perimeter(self): 104 | return 2 * self.w + self.h * 2 105 | 106 | 107 | class RhombusPerimeterCalculator(SquarePerimeterCalculator): 108 | "Compute rhombus perimeter" 109 | 110 | def __init__(self, side: float): 111 | super().__init__(side) 112 | self.exp = """ 113 | ===================== 114 | Perimeter of Rhombus 115 | ===================== 116 | A 117 | /\\ 118 | / \ side 119 | B/ \ D 120 | \ / 121 | \ / side 122 | \/ 123 | C 124 | 125 | Perimeter of Rhombus is |AB| + |BC| + |CD| + |DA| 126 | which can also be expressed as 4 * side 127 | """ 128 | 129 | 130 | class ParallelogramPerimeterCalculator(PerimeterCalculator): 131 | def __init__(self, horizontal_side: float, vertical_side: float): 132 | self.hside = horizontal_side 133 | self.vside = vertical_side 134 | self.exp = """ 135 | =========================== 136 | Perimeter of Parallelogram 137 | =========================== 138 | 139 | hside 140 | A ______________ D 141 | / / 142 | / / vside 143 | / / 144 | B /_____________/ C 145 | 146 | Perimeter of Parallelogram is |AB| + |BC| + |CD| + |DA| 147 | which can also be expressed as 2 * vside + 2 * hside 148 | 149 | """ 150 | self.formula = "2 * hside + 2 * vside" 151 | 152 | def perimeter(self): 153 | return 2 * self.hside + 2 * self.vside 154 | 155 | 156 | class ClosedPolygonPerimeterCalculator(PerimeterCalculator): 157 | "Compute closed shaped polygon" 158 | 159 | def __init__(self, diff_list: List[float]): 160 | self.dlist = diff_list 161 | self.formula = "\sum_{i=1}^{k=(number of sides)} distance_i" 162 | self.exp = """ 163 | ============================= 164 | Perimeter of a Closed Polygon 165 | ============================= 166 | 167 | J______________ I 168 | / \\ 169 | A/ \ H 170 | | ____ / 171 | | /D E\ / 172 | |____/ \___/ 173 | B C F G 174 | 175 | 176 | Perimeter of Closed Polygon is 177 | |AB| + |BC| + |CD| + |DE| + |EF| + |FG| + |GH| + |HI| + |IJ| + |JA| 178 | 179 | which can be briefly expressed as 180 | 181 | .. math:: 182 | 183 | \sum_{i=1}^{k=number of sides} d_i where 184 | 185 | d_i \in D = {f(x_1, x_2), f(x_2, x_3), ..., f(x_j, x_{j+1})} 186 | x_j \in Ordered set of Polygon Corners = {A, B, C, D, ... } 187 | f(x_j, x_{j+1}) = |x_j - x_{j+1}| 188 | 189 | """ 190 | 191 | def perimeter(self): 192 | result = 0 193 | for absolute_difference_between_two_corners in self.dlist: 194 | result = result + absolute_difference_between_two_corners 195 | return result 196 | 197 | 198 | class CirclePerimeterCalculator(Calculator): 199 | "Perimeter of a circle" 200 | def __init__(self, radius: float): 201 | self.r = radius 202 | self.exp = """ 203 | ==================== 204 | Perimeter of Circle 205 | ==================== 206 | 207 | Perimeter of a circle is approximated by the use of regular polygons. 208 | It is considered as the limit of the perimeter of a regular polygon 209 | with infinite sides. 210 | 211 | """ 212 | 213 | 214 | def main(): 215 | print("Welcome to Perimeter Calculator") 216 | choice = input( 217 | """ 218 | Choose your calculator: 219 | 220 | - r -> rectangle 221 | - t -> triangle 222 | - s -> square 223 | - rh -> rhombus 224 | - p -> parallelogram 225 | - cp -> closed polygon 226 | 227 | """ 228 | ) 229 | if choice == "t": 230 | sides = input("Enter sides for triangle separated by comma Ex. 1.7,5.3,3.0: ") 231 | sides = list(map(float, sides.split(","))) 232 | calc = TrianglePerimCalculator(sides) 233 | elif choice == "r": 234 | sides = input( 235 | "Enter width and height for rectangle separated by comma Ex. 1.7,5.3: " 236 | ) 237 | sides = list(map(float, sides.split(","))) 238 | calc = RectanglePerimeterCalculator(width=sides[0], height=sides[1]) 239 | elif choice == "s": 240 | side = input("Enter a side for square: ") 241 | side = float(side) 242 | calc = SquarePerimeterCalculator(side) 243 | elif choice == "rh": 244 | side = input("Enter a side for rhombus: ") 245 | side = float(side) 246 | calc = RhombusPerimeterCalculator(side) 247 | elif choice == "p": 248 | sides = input( 249 | "Enter horizontal and vertical side length for parallelogram" 250 | " separated by comma Ex. 1.7,5.3: " 251 | ) 252 | sides = list(map(float, sides.split(","))) 253 | calc = ParallelogramPerimeterCalculator( 254 | horizontal_side=sides[0], vertical_side=sides[1] 255 | ) 256 | elif choice == "cp": 257 | sides = input( 258 | "Enter an ordered list of distances between corners of polygon" 259 | " separated by comma Ex. 1.7,5.3,2.3,65.2,23.5,...: " 260 | ) 261 | sides = list(map(float, sides.split(","))) 262 | calc = ClosedPolygonPerimeterCalculator(sides) 263 | else: 264 | calc = None 265 | raise ValueError("Unknown choice: " + choice) 266 | calc.result() 267 | 268 | 269 | if __name__ == "__main__": 270 | main() 271 | -------------------------------------------------------------------------------- /calc/calculus/differential.py: -------------------------------------------------------------------------------- 1 | # Simple calculator for differentials intended for educative use 2 | # author: Kaan Eraslan 3 | # license: see, LICENSE 4 | 5 | import math 6 | 7 | from calc.basecalc import Calculator 8 | from typing import Callable, List 9 | import inspect 10 | 11 | 12 | class D1DiffCalculator(Calculator): 13 | "Differential calculator for single dimension" 14 | 15 | def __init__(self, param, diff_step): 16 | "constructor" 17 | self.step = diff_step 18 | self.param = param 19 | self.formula = """ 20 | f'(x1) = (f(x2) - f(x1)) / (x2 - x1) where (x2-x1) decreases into 0""" 21 | self.exp = """ 22 | ============== 23 | Differentials 24 | ============== 25 | 26 | Differentials measure the rate of change and 27 | respond to the following question: 28 | 29 | What is the difference between the current instant and the instant 30 | before? 31 | 32 | This question supposes several things under the hood: 33 | - Current instant and the instant before are comparable. 34 | - The same function can be applied to both instances. 35 | 36 | Here is the formula: {0} 37 | 38 | Terms: 39 | - f(x2): corresponds to current instant 40 | - f(x1): corresponds to instant before 41 | - (x2 - x1): is the distance between current instant and instant 42 | before, it can be as small as possible, it is almost 0. 43 | """.format( 44 | self.formula 45 | ) 46 | 47 | def f(self, x): 48 | "a simple function " 49 | return x ** 2 + 7 50 | 51 | def show_formula(self): 52 | print(self.formula) 53 | print("\nHere is the f we are using: \n") 54 | print(inspect.getsource(self.f)) 55 | 56 | def show_explanation(self): 57 | print(self.exp) 58 | 59 | def de(self, fn, x, step): 60 | "take derivative of a function with respect to given variable and step" 61 | instant_before = fn(x) 62 | current_instant = fn(x + step) 63 | result = (current_instant - instant_before) / step 64 | return result 65 | 66 | def derivative_of_f(self): 67 | instant_before = self.f(self.param) 68 | current_instant = self.f(self.param + self.step) 69 | result = (current_instant - instant_before) / self.step 70 | return result 71 | 72 | def result(self): 73 | self.show_explanation() 74 | self.show_formula() 75 | print("\nHere is our implementation:\n") 76 | print(inspect.getsource(self.derivative_of_f)) 77 | print("\nGives the following result:\n") 78 | print(str(self.derivative_of_f())) 79 | 80 | 81 | class D1Rules(D1DiffCalculator): 82 | def __init__(self, param, diff_step): 83 | super().__init__(param, diff_step) 84 | self.add_rule = """ 85 | k(x) = f(x) + g(x) 86 | 87 | k'(x) = f'(x) + g'(x) 88 | """ 89 | self.sub_rule = """ 90 | k(x) = f(x) - g(x) 91 | 92 | k'(x) = f'(x) - g'(x) 93 | """ 94 | self.prod_rule = """ 95 | k(x) = f(x)*g(x) 96 | 97 | k'(x) = f'(x)*g(x) + f(x)*g'(x) 98 | """ 99 | self.div_rule = """ 100 | k(x) = f(x) / g(x) 101 | 102 | k'(x) = [f'(x)g(x) - f(x)g'(x)] / g(x) * g(x) 103 | """ 104 | self.chain_rule = """ 105 | k(x) = f( g(x) ) 106 | 107 | k'(x) = f'(g(x)) * g'(x) 108 | """ 109 | 110 | def g(self, x): 111 | "a simple function" 112 | return x ** 3 + 2 113 | 114 | def add_fn(self, x): 115 | return self.f(x) + self.g(x) 116 | 117 | def deriv_add_fn(self, x, step): 118 | return self.de(self.f, x, step) + self.de(self.g, x, step) 119 | 120 | def sub_fn(self, x): 121 | return self.f(x) - self.g(x) 122 | 123 | def de_sub_fn(self, x, step): 124 | return self.de(self.f, x, step) - self.de(self.g, x, step) 125 | 126 | def chain_fn(self, x): 127 | return self.f(self.g(x)) 128 | 129 | def de_chain_fn(self, x, step): 130 | d_g = self.de(self.g, x, step) 131 | gres = self.g(x) 132 | d_f_g = self.de(self.f, gres, step) 133 | return d_g * d_f_g 134 | 135 | def prod_fn(self, x): 136 | return self.f(x) * self.g(x) 137 | 138 | def de_prod_fn(self, x, step): 139 | d_g = self.de(self.g, x, step) 140 | d_f = self.de(self.f, x, step) 141 | gres = self.g(x) 142 | fres = self.f(x) 143 | return (d_f * gres) + (fres * d_g) 144 | 145 | def div_fn(self, x): 146 | return self.f(x) / self.g(x) 147 | 148 | def de_div_fn(self, x, step): 149 | d_g = self.de(self.g, x, step) 150 | d_f = self.de(self.f, x, step) 151 | gres = self.g(x) 152 | fres = self.f(x) 153 | p1 = d_f * gres 154 | p2 = fres * d_g 155 | return (p1 - p2) / (d_g * d_g) 156 | 157 | def show_rule(self, rname: str, rule, kx, d_kx, res1, res2): 158 | print("\n{0} Demonstration".format(rname.capitalize())) 159 | print("---------------------------\n\n") 160 | print("Here is the {0}: ".format(rname)) 161 | print(rule, "\n\n") 162 | print("Here is the body of k(x):\n") 163 | print(inspect.getsource(kx)) 164 | print("Here is the body of k'(x):\n") 165 | print(inspect.getsource(d_kx)) 166 | print("Let's see if the rule holds: ") 167 | print( 168 | "Here is the result of the derivative of k(x) computed directly: ", 169 | str(res2), 170 | ) 171 | print( 172 | "Here is the result of k(x) computed in parts as seen at right of =: ", 173 | str(res1), 174 | ) 175 | 176 | def show_addition_rule(self): 177 | result1 = self.de(self.add_fn, self.param, self.step) 178 | result2 = self.deriv_add_fn(self.param, self.step) 179 | self.show_rule( 180 | rname="addition rule", 181 | rule=self.add_rule, 182 | kx=self.add_fn, 183 | d_kx=self.deriv_add_fn, 184 | res1=result1, 185 | res2=result2, 186 | ) 187 | 188 | def show_subtraction_rule(self): 189 | result1 = self.de(self.sub_fn, self.param, self.step) 190 | result2 = self.de_sub_fn(self.param, self.step) 191 | self.show_rule( 192 | rname="subtraction rule", 193 | rule=self.sub_rule, 194 | kx=self.sub_fn, 195 | d_kx=self.de_sub_fn, 196 | res1=result1, 197 | res2=result2, 198 | ) 199 | 200 | def show_chain_rule(self): 201 | result2 = self.de_chain_fn(self.param, self.step) 202 | result1 = self.de(self.chain_fn, self.param, self.step) 203 | self.show_rule( 204 | rname="chain rule", 205 | rule=self.chain_rule, 206 | kx=self.chain_fn, 207 | d_kx=self.de_chain_fn, 208 | res1=result1, 209 | res2=result2, 210 | ) 211 | 212 | def show_product_rule(self): 213 | result1 = self.de(self.prod_fn, self.param, self.step) 214 | result2 = self.de_prod_fn(self.param, self.step) 215 | self.show_rule( 216 | rname="product rule", 217 | rule=self.prod_rule, 218 | kx=self.prod_fn, 219 | d_kx=self.de_prod_fn, 220 | res1=result1, 221 | res2=result2, 222 | ) 223 | 224 | def show_div_rule(self): 225 | result1 = self.de(self.div_fn, self.param, self.step) 226 | result2 = self.de_div_fn(self.param, self.step) 227 | self.show_rule( 228 | rname="division rule", 229 | rule=self.div_rule, 230 | kx=self.div_fn, 231 | d_kx=self.de_div_fn, 232 | res1=result1, 233 | res2=result2, 234 | ) 235 | 236 | 237 | def main(): 238 | print("Welcome to simple differential calculator") 239 | param = input("Enter a floating number [Ex. 12.2, 42.1, etc]: ") 240 | param = float(param) 241 | print("Using 0.0001 as a step value") 242 | calc = D1DiffCalculator(param, 0.001) 243 | calc.result() 244 | cont = input( 245 | """ 246 | Would you like to learn about rules of derivative as well ? 247 | Available choices are: 248 | - a: addition rule 249 | - s: subtraction rule 250 | - p: product rule 251 | - d: division rule 252 | - c: chain rule 253 | - q: quit application 254 | """ 255 | ) 256 | if cont == "q": 257 | return 0 258 | ruler = D1Rules(param, 0.0001) 259 | if cont == "a": 260 | ruler.show_addition_rule() 261 | elif cont == "s": 262 | ruler.show_subtraction_rule() 263 | elif cont == "c": 264 | ruler.show_chain_rule() 265 | elif cont == "d": 266 | ruler.show_div_rule() 267 | elif cont == "p": 268 | ruler.show_product_rule() 269 | 270 | 271 | if __name__ == "__main__": 272 | main() 273 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | 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Patents. 472 | 473 | A "contributor" is a copyright holder who authorizes use under this 474 | License of the Program or a work on which the Program is based. The 475 | work thus licensed is called the contributor's "contributor version". 476 | 477 | A contributor's "essential patent claims" are all patent claims 478 | owned or controlled by the contributor, whether already acquired or 479 | hereafter acquired, that would be infringed by some manner, permitted 480 | by this License, of making, using, or selling its contributor version, 481 | but do not include claims that would be infringed only as a 482 | consequence of further modification of the contributor version. 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You may not convey a covered 525 | work if you are a party to an arrangement with a third party that is 526 | in the business of distributing software, under which you make payment 527 | to the third party based on the extent of your activity of conveying 528 | the work, and under which the third party grants, to any of the 529 | parties who would receive the covered work from you, a discriminatory 530 | patent license (a) in connection with copies of the covered work 531 | conveyed by you (or copies made from those copies), or (b) primarily 532 | for and in connection with specific products or compilations that 533 | contain the covered work, unless you entered into that arrangement, 534 | or that patent license was granted, prior to 28 March 2007. 535 | 536 | Nothing in this License shall be construed as excluding or limiting 537 | any implied license or other defenses to infringement that may 538 | otherwise be available to you under applicable patent law. 539 | 540 | 12. No Surrender of Others' Freedom. 541 | 542 | If conditions are imposed on you (whether by court order, agreement or 543 | otherwise) that contradict the conditions of this License, they do not 544 | excuse you from the conditions of this License. If you cannot convey a 545 | covered work so as to satisfy simultaneously your obligations under this 546 | License and any other pertinent obligations, then as a consequence you may 547 | not convey it at all. For example, if you agree to terms that obligate you 548 | to collect a royalty for further conveying from those to whom you convey 549 | the Program, the only way you could satisfy both those terms and this 550 | License would be to refrain entirely from conveying the Program. 551 | 552 | 13. Use with the GNU Affero General Public License. 553 | 554 | Notwithstanding any other provision of this License, you have 555 | permission to link or combine any covered work with a work licensed 556 | under version 3 of the GNU Affero General Public License into a single 557 | combined work, and to convey the resulting work. The terms of this 558 | License will continue to apply to the part which is the covered work, 559 | but the special requirements of the GNU Affero General Public License, 560 | section 13, concerning interaction through a network will apply to the 561 | combination as such. 562 | 563 | 14. Revised Versions of this License. 564 | 565 | The Free Software Foundation may publish revised and/or new versions of 566 | the GNU General Public License from time to time. Such new versions will 567 | be similar in spirit to the present version, but may differ in detail to 568 | address new problems or concerns. 569 | 570 | Each version is given a distinguishing version number. If the 571 | Program specifies that a certain numbered version of the GNU General 572 | Public License "or any later version" applies to it, you have the 573 | option of following the terms and conditions either of that numbered 574 | version or of any later version published by the Free Software 575 | Foundation. If the Program does not specify a version number of the 576 | GNU General Public License, you may choose any version ever published 577 | by the Free Software Foundation. 578 | 579 | If the Program specifies that a proxy can decide which future 580 | versions of the GNU General Public License can be used, that proxy's 581 | public statement of acceptance of a version permanently authorizes you 582 | to choose that version for the Program. 583 | 584 | Later license versions may give you additional or different 585 | permissions. However, no additional obligations are imposed on any 586 | author or copyright holder as a result of your choosing to follow a 587 | later version. 588 | 589 | 15. Disclaimer of Warranty. 590 | 591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY 592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT 593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY 594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, 595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM 597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF 598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 599 | 600 | 16. Limitation of Liability. 601 | 602 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS 604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY 605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE 606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF 607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD 608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), 609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF 610 | SUCH DAMAGES. 611 | 612 | 17. Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | --------------------------------------------------------------------------------