remove numpy dependency

mtl/utils.py

@@ -3,7 +3,6 @@ from functools import reduce, wraps
 from math import isfinite
 
 from discrete_signals import signal
-import numpy as np
 
 from mtl import ast
 from mtl.ast import (And, G, Neg, Next, WeakUntil,
@@ -80,7 +79,7 @@ def _interval_discretizable(itvl, dt):
     l, u = itvl.lower / dt, itvl.upper / dt
     if not (isfinite(l) and isfinite(u)):
         return False
-    return np.isclose(l, round(l)) and np.isclose(u, round(u))
+    return max(abs(l - round(l)), abs(u - round(u)))
 
 
 def _distribute_next(phi, i=0):

requirements.txt

@@ -4,10 +4,10 @@ attrs==18.2.0
 codecov==2.0.15
 funcy==1.11
 lenses==0.5.0
-hypothesis==3.66.30 # pyup: ignore
+hypothesis==3.66.30
 parsimonious==0.8.1
-pytest==3.2.3 # pyup: ignore
-pytest-cov==2.5.1 # pyup: ignore
-pytest-flake8==0.9 # pyup: ignore
-pytest-sugar==0.9.1 # pyup: ignore
-pytest-xdist==1.22.5 # pyup: ignore
+pytest==3.2.3
+pytest-cov==2.5.1
+pytest-flake8==0.9
+pytest-sugar==0.9.1
+pytest-xdist==1.22.5