def lnPressed(self):
self.equalsPressed()
if self.labelAns == 'ERROR':
return
try:
self.ans = str(Mathlibrary.ln(float(self.labelAns.text())))
except:
self.labelAns.setText('ERROR')
self.labelWrite.setText('')
self.lastCharacter = ''
self.lastButton = ''
self.decimalPoint = False
self.ans = '0'
return
self.labelAns.setText(self.ans)
self.labelWrite.setText('')
self.lastCharacter = ''
self.lastButton = 'dig'
self.decimalPoint = False
class MathLibraryTestLn(unittest.TestCase):
def setUp(self):
self.mathlib = Mathlibrary()
def testLnNegative(self):
with self.assertRaises(ValueError):
self.mathlib.ln(-123)
with self.assertRaises(ValueError):
self.mathlib.ln(-0.00001)
with self.assertRaises(ValueError):
self.mathlib.ln(-41928501)
def testLnZero(self):
with self.assertRaises(ValueError):
self.mathlib.ln(0)
with self.assertRaises(ValueError):
self.mathlib.ln(0.00000)
def testLnNaturalNumberGreaterThanOne(self):
self.assertAlmostEqual(self.mathlib.ln(math.e), 1)
self.assertAlmostEqual(self.mathlib.ln(2), 0.693147180)
self.assertAlmostEqual(self.mathlib.ln(42), 3.73766961828)
self.assertAlmostEqual(self.mathlib.ln(17349), 9.76129014682632)
def testLnNaturalNumberLowerThanOne(self):
self.assertAlmostEqual(self.mathlib.ln(0.8257), -0.19152376755875)
self.assertAlmostEqual(self.mathlib.ln(0.541), -0.6143360001356)
self.assertAlmostEqual(self.mathlib.ln(0.0042), -5.472670753692814)