Introduced Min and Max in sympy_compat.py and shifted tests to test_sympy_compat.py

Author: ShikharJ

symengine/lib/symengine_wrapper.pxd

@@ -130,10 +130,10 @@ cdef class PyFunction(FunctionSymbol):
 cdef class Abs(Function):
     pass
 
-cdef class Max(Function):
+cdef class _Max(Function):
     pass
 
-cdef class Min(Function):
+cdef class _Min(Function):
     pass
 
 cdef class Gamma(Function):

symengine/lib/symengine_wrapper.pyx

@@ -46,9 +46,9 @@ cdef c2py(RCP[const symengine.Basic] o):
     elif (symengine.is_a_Abs(deref(o))):
         r = Abs.__new__(Abs)
     elif (symengine.is_a_Max(deref(o))):
-        r = Max.__new__(Max)
+        r = _Max.__new__(_Max)
     elif (symengine.is_a_Min(deref(o))):
-        r = Min.__new__(Min)
+        r = _Min.__new__(_Min)
     elif (symengine.is_a_Gamma(deref(o))):
         r = Gamma.__new__(Gamma)
     elif (symengine.is_a_Derivative(deref(o))):
@@ -213,9 +213,9 @@ def sympy2symengine(a, raise_error=False):
     elif isinstance(a, sympy.Abs):
         return abs(sympy2symengine(a.args[0], raise_error))
     elif isinstance(a, sympy.Max):
-        return max(*a.args)
+        return _max(*a.args)
     elif isinstance(a, sympy.Min):
-        return min(*a.args)
+        return _min(*a.args)
     elif isinstance(a, sympy.gamma):
         return gamma(a.args[0])
     elif isinstance(a, sympy.Derivative):
@@ -1400,7 +1400,11 @@ cdef class Abs(Function):
         arg = c2py(deref(X).get_arg())._sage_()
         return abs(arg)
 
-cdef class Max(Function):
+cdef class _Max(Function):
+    '''
+    Class named as such to prevent namespace issues with
+    Python's min. Import as Min for aesthetics.
+    '''
 
     def _sympy_(self):
         cdef RCP[const symengine.Max] X = \
@@ -1422,7 +1426,11 @@ cdef class Max(Function):
             s.append(c2py(<RCP[const symengine.Basic]>(Y[i]))._sage_())
         return sage.max(*s)
 
-cdef class Min(Function):
+cdef class _Min(Function):
+    '''
+    Class named as such to prevent namespace issues with
+    Python's min. Import as Min for aesthetics.
+    '''
 
     def _sympy_(self):
         cdef RCP[const symengine.Min] X = \
@@ -2355,15 +2363,15 @@ def log(x, y = None):
     cdef Basic Y = _sympify(y)
     return c2py(symengine.log(X.thisptr, Y.thisptr))
 
-def max(*args):
+def _max(*args):
     cdef symengine.vec_basic v
     cdef Basic e_
     for e in args:
         e_ = sympify(e)
         v.push_back(e_.thisptr)
     return c2py(symengine.max(v))
 
-def min(*args):
+def _min(*args):
     cdef symengine.vec_basic v
     cdef Basic e_
     for e in args:

symengine/sympy_compat.py

@@ -151,6 +151,20 @@ def __new__(cls, a):
         return symengine.tan(a)
 
 
+class Max(Basic):
+    _classes = (symengine._Max,)
+
+    def __new__(cls, *args):
+        return symengine._max(*args)
+
+
+class Min(Basic):
+    _classes = (symengine._Min,)
+
+    def __new__(cls, *args):
+        return symengine._min(*args)
+
+
 class gamma(_RegisteredFunction):
     _classes = (symengine.Gamma,)
 

symengine/tests/test_sympy_compat.py

@@ -1,6 +1,6 @@
 from symengine.sympy_compat import (Integer, Rational, S, Basic, Add, Mul,
-    Pow, symbols, Symbol, log, sin, sech, csch, zeros, atan2, Number, Float,
-    symengine)
+    Pow, symbols, Symbol, log, sin, cos, sech, csch, zeros, atan2, Number, Float,
+    symengine, Min, Max)
 from symengine.utilities import raises
 
 
@@ -86,6 +86,38 @@ def test_Pow():
     assert isinstance(i, Basic)
 
 
+def test_Max():
+    x = Symbol("x")
+    y = Symbol("y")
+    z = Symbol("z")
+    assert Max(Integer(6)/3, 1) == 2
+    assert Max(-2, 2) == 2
+    assert Max(2, 2) == 2
+    assert Max(0.2, 0.3) == 0.3
+    assert Max(x, x) == x
+    assert Max(x, y) == Max(y, x)
+    assert Max(x, y, z) == Max(z, y, x)
+    assert Max(x, Max(y, z)) == Max(z, y, x)
+    assert Max(1000, 100, -100, x, y, z) == Max(x, y, z, 1000)
+    assert Max(cos(x), sin(x)) == Max(sin(x), cos(x))
+
+
+def test_Min():
+    x = Symbol("x")
+    y = Symbol("y")
+    z = Symbol("z")
+    assert Min(Integer(6)/3, 1) == 1
+    assert Min(-2, 2) == -2
+    assert Min(2, 2) == 2
+    assert Min(0.2, 0.3) == 0.2
+    assert Min(x, x) == x
+    assert Min(x, y) == Min(y, x)
+    assert Min(x, y, z) == Min(z, y, x)
+    assert Min(x, Min(y, z)) == Min(z, y, x)
+    assert Min(1000, 100, -100, x, y, z) == Min(x, y, z, -100)
+    assert Min(cos(x), sin(x)) == Min(cos(x), sin(x))
+
+
 def test_sin():
     x = symbols("x")
     i = sin(0)