def test_mul(self):
t1 = formula.Term("t1")
t2 = formula.Term("t2")
f = t1 * t2
self.assert_(isinstance(f, formula.Formula))
intercept = formula.Term("intercept")
f = t1 * intercept
self.assertEqual(str(f), str(formula.Formula(t1)))
f = intercept * t1
self.assertEqual(str(f), str(formula.Formula(t1)))
f = ['a'] * 3 + ['b'] * 3 + ['c'] * 2
fac = formula.Factor('ff', f)
fac.namespace = {'ff': f}
#Example: formula with factor
# I don't manage to combine factors with formulas, e.g. a joint
# designmatrix
# also I don't manage to get contrast matrices with factors
# it looks like I might have to add namespace for dummies myself ?
# even then combining still doesn't work
f5 = formula.Term('A') + fac
namespace['A'] = form.namespace['A']
formula.Formula(fac).design()
'''
>>> formula.Formula(fac).design()
array([[ 1., 0., 0.],
[ 1., 0., 0.],
[ 1., 0., 0.],
[ 0., 1., 0.],
[ 0., 1., 0.],
[ 0., 1., 0.],
[ 0., 0., 1.],
[ 0., 0., 1.]])
>>> contrast.Contrast(formula.Term('(ff==a)'), fac).matrix
Traceback (most recent call last):
File "c:\...\scikits\statsmodels\sandbox\contrast_old.py", line 112, in _get_matrix
if __name__ == '__main__':
import numpy.random as R
n = 100
X = np.array([0]*n + [1]*n)
b = 0.4
lin = 1 + b*X
Y = R.standard_exponential((2*n,)) / lin
delta = R.binomial(1, 0.9, size=(2*n,))
subjects = [Observation(Y[i], delta[i]) for i in range(2*n)]
for i in range(2*n):
subjects[i].X = X[i]
import statsmodels.sandbox.formula as F
x = F.Quantitative('X')
f = F.Formula(x)
c = CoxPH(subjects, f)
# c.cache()
# temp file cleanup doesn't work on windows
c = CoxPH(subjects, f, time_dependent=True)
c.cache() #this creates tempfile cache,
# no tempfile cache is created in normal use of CoxPH
#res = c.newton([0.4]) #doesn't work anymore
res=c.fit([0.4],method="bfgs")
print res.params
print dir(c)
#print c.fit(Y)