Merge pull request #152 from ShikharJ/Ccode

Wrapped ccode and implemented class CodePrinter

Author: isuruf

symengine/CMakeLists.txt

@@ -2,6 +2,6 @@ add_subdirectory(lib)
 add_subdirectory(tests)
 
 set(PY_PATH ${PYTHON_INSTALL_PATH}/symengine)
-install(FILES __init__.py utilities.py compatibility.py sympy_compat.py functions.py
+install(FILES __init__.py utilities.py compatibility.py sympy_compat.py functions.py printing.py
     DESTINATION ${PY_PATH}
     )

symengine/lib/symengine.pxd

@@ -802,3 +802,6 @@ IF HAVE_SYMENGINE_MPC:
 
 cdef extern from "<symengine/parser.h>" namespace "SymEngine":
     RCP[const Basic] parse(const string &n) nogil except +
+
+cdef extern from "<symengine/codegen.h>" namespace "SymEngine":
+    string ccode(const Basic &x) nogil except +

symengine/lib/symengine_wrapper.pyx

@@ -389,8 +389,8 @@ cdef class _DictBasic(object):
                 self.add(key, value)
 
     def add(self, key, value):
-        cdef Basic K = _sympify(key)
-        cdef Basic V = _sympify(value)
+        cdef Basic K = sympify(key)
+        cdef Basic V = sympify(value)
         cdef symengine.std_pair_rcp_const_basic_rcp_const_basic pair
         pair.first = K.thisptr
         pair.second = V.thisptr
@@ -405,27 +405,27 @@ cdef class _DictBasic(object):
         return self.c.size()
 
     def __getitem__(self, key):
-        cdef Basic K = _sympify(key)
+        cdef Basic K = sympify(key)
         it = self.c.find(K.thisptr)
         if it == self.c.end():
             raise KeyError(key)
         else:
             return c2py(deref(it).second)
 
     def __setitem__(self, key, value):
-        cdef Basic K = _sympify(key)
-        cdef Basic V = _sympify(value)
+        cdef Basic K = sympify(key)
+        cdef Basic V = sympify(value)
         self.c[K.thisptr] = V.thisptr
 
     def clear(self):
         self.clear()
 
     def __delitem__(self, key):
-        cdef Basic K = _sympify(key)
+        cdef Basic K = sympify(key)
         self.c.erase(K.thisptr)
 
     def __contains__(self, key):
-        cdef Basic K = _sympify(key)
+        cdef Basic K = sympify(key)
         it = self.c.find(K.thisptr)
         return it != self.c.end()
 
@@ -3393,5 +3393,9 @@ def has_symbol(obj, symbol=None):
         return symengine.has_symbol(deref(b.thisptr),
                 deref(symengine.rcp_static_cast_Symbol(s.thisptr)))
 
+def ccode(expr):
+    cdef Basic expr_ = sympify(expr)
+    return symengine.ccode(deref(expr_.thisptr)).decode("utf-8")
+
 # Turn on nice stacktraces:
 symengine.print_stack_on_segfault()

symengine/printing.py

@@ -0,0 +1,24 @@
+from symengine.lib.symengine_wrapper import ccode, _sympify, Basic
+
+class CCodePrinter:
+
+    def doprint(self, expr, assign_to=None):
+        if not isinstance(assign_to, (Basic, type(None), str)):
+            raise TypeError("{0} cannot assign to object of type {1}".format(
+                    type(self).__name__, type(assign_to)))
+
+        expr = _sympify(expr)
+        if not assign_to:
+            if expr.is_Matrix:
+                raise RuntimeError("Matrices need a assign_to parameter")
+            return ccode(expr)
+
+        assign_to = str(assign_to)
+        if not expr.is_Matrix:
+            return "{} = {};".format(assign_to, ccode(expr))
+
+        code_lines = []
+        for i, element in enumerate(expr):
+            code_line = '{}[{}] = {};'.format(assign_to, i, element)
+            code_lines.append(code_line)
+        return '\n'.join(code_lines)

symengine/tests/CMakeLists.txt

@@ -8,6 +8,7 @@ install(FILES __init__.py
     test_number.py
     test_matrices.py
     test_ntheory.py
+    test_printing.py
     test_sage.py
     test_series_expansion.py
     test_subs.py

symengine/tests/test_printing.py

@@ -0,0 +1,27 @@
+from symengine.utilities import raises
+from symengine.lib.symengine_wrapper import (ccode, Symbol, sqrt, Pow, Max, sin, Integer, MutableDenseMatrix)
+from symengine.printing import CCodePrinter
+
+def test_ccode():
+    x = Symbol("x")
+    y = Symbol("y")
+    assert ccode(x) == "x"
+    assert ccode(x**3) == "pow(x, 3)"
+    assert ccode(x**(y**3)) == "pow(x, pow(y, 3))"
+    assert ccode(x**-1.0) == "pow(x, -1.0)"
+    assert ccode(Max(x, x*x)) == "max(x, pow(x, 2))"
+    assert ccode(sin(x)) == "sin(x)"
+    assert ccode(Integer(67)) == "67"
+    assert ccode(Integer(-1)) == "-1"
+
+def test_CCodePrinter():
+    x = Symbol("x")
+    y = Symbol("y")
+    myprinter = CCodePrinter()
+
+    assert myprinter.doprint(1+x, "bork") == "bork = 1 + x;"
+    assert myprinter.doprint(1*x) == "x"
+    assert myprinter.doprint(MutableDenseMatrix(1, 2, [x, y]), "larry") == "larry[0] = x;\nlarry[1] = y;"
+    raises(TypeError, lambda: myprinter.doprint(sin(x), Integer))
+    raises(RuntimeError, lambda: myprinter.doprint(MutableDenseMatrix(1, 2, [x, y])))
+