tests.py

import slopefield as sf
import numpy as np
import unittest

class TestTick(unittest.TestCase):
    def setUp(self):
        self.trans=dict()
        self.trans['ym'],self.trans['yb'] = sf.translation(-1,10,1,500)
        self.trans['tm'],self.trans['tb'] = sf.translation(-1,10,1,500)
    def testArithmetic(self):
        r = sf.tick(np.array([1]),np.array([1]),lambda t,y:2*t-y,2**0.5,trans=self.trans)
        self.assertAlmostEqual(r.sum(), 2000)
    def testDivideZero(self):
        r = sf.tick(np.array([1]),np.array([0]),lambda t,y:t/y,1,trans=self.trans)
        self.assertAlmostEqual(r.sum(),1510)

class TestSanitization(unittest.TestCase):
    def testValidFunction(self):
        r = sf.sanitize_fn('sin(2+pi)*e^(1.2) + 1/2 - sqrt(2)')
        self.assertEqual(r(1,1),-3.933187336977838)
        r = sf.sanitize_fn('t+y/2')
        self.assertEqual(r(1,1),1.5,'t=1,y=1')
        self.assertEqual(r(-1,4),1,'t=-1,y=1')
    def testInvalidWord(self):
        self.assertRaises(sf.SanitizeError,sf.sanitize_fn,'3 + int(1.2)')
    def testSyntaxError(self):
        self.assertRaises(sf.SanitizeError,sf.sanitize_fn,'3+*2')
    def testNameError(self):
        self.assertRaises(sf.SanitizeError,sf.sanitize_fn,'sin.t')
    def testSanityError(self):
        self.assertRaises(sf.SanitizeError,sf.sanitize_fn,'sin + t')

class TestClip(unittest.TestCase):
    def testClipMiddle(self):
        self.assertEqual(sf.clip(1,5,10),5)
    def testClipRight(self):
        self.assertEqual(sf.clip(1,11,10),10)
    def testClipLeft(self):
        self.assertEqual(sf.clip(1,0,10),1)

class TestMisc(unittest.TestCase):
    def testSvgTick(self):
        r = sf.svg_tick([1.23,5.46,5.24,1.33])
        self.assertEqual(r,'<line x1 = "1.2" y1 = "5.5" x2 = "5.2" y2 = "1.3" />')

class TestTranslations(unittest.TestCase):
    def testTranslationGenerator(self):
        a,b = sf.translation(1,2,3,5)
        self.assertEqual(a*1+b,2)
        self.assertEqual(a*3+b,5)

class TestSlopeFieldGenerator(unittest.TestCase):
    def setUp(self):
        self.trans = {'tm':1,'tb':0,'ym':1,'yb':0}
    def testSingleTick(self):
        d = {'tmax':1,'tmin':0,'tticks':1,'ymin':0,'ymax':2,'yticks':1,'fn':lambda t,y:1}
        r = sf.slopefield(d,trans=self.trans)
        self.assertAlmostEqual(r.sum(), 3)
    def testMultipleTick(self):
        d = {'tmax':1,'tmin':0,'tticks':20,'ymin':0,'ymax':2,'yticks':25,'fn':lambda t,y:1}
        r = len(list(sf.slopefield(d,trans=self.trans)))
        self.assertEqual(r,20*25)

if __name__ == "__main__":
    unittest.main()