[RFC] Add latex representation to DenseMatrix

appveyor.yml

@@ -54,7 +54,7 @@ install:
 - git clone https://github.com/sympy/symengine symengine-cpp
 
 - if [%COMPILER%]==[MSVC15] call %CONDA_INSTALL_LOCN%\Scripts\activate.bat
-- if [%COMPILER%]==[MSVC15] conda update --yes --quiet conda
+- if [%COMPILER%]==[MSVC15] conda install --yes --quiet conda python=3.6
 - if [%COMPILER%]==[MSVC15] conda config --add channels conda-forge
 - if [%COMPILER%]==[MSVC15] if [%BUILD_TYPE%]==[Debug] conda config --add channels symengine/label/debug
 - if [%COMPILER%]==[MSVC15] conda install --yes mpir=3.0.0 vc=14

symengine/lib/symengine.pxd

@@ -1099,6 +1099,7 @@ cdef extern from "<symengine/solve.h>" namespace "SymEngine":
 cdef extern from "<symengine/printers.h>" namespace "SymEngine":
     string ccode(const Basic &x) nogil except +
     string latex(const Basic &x) nogil except +
+    string latex(const DenseMatrix &x, unsigned max_rows, unsigned max_cols) nogil except +
 
 ## Defined in 'symengine/cwrapper.cpp'
 cdef struct CRCPBasic:

symengine/lib/symengine_wrapper.pyx

@@ -3241,6 +3241,12 @@ cdef class DenseMatrixBase(MatrixBase):
     def __str__(self):
         return deref(self.thisptr).__str__().decode("utf-8")
 
+    def _repr_latex_(self):
+        if repr_latex[0]:
+            return "${}$".format(latex(self))
+        else:
+            return None
+
     def __add__(a, b):
         a = _sympify(a, False)
         b = _sympify(b, False)
@@ -5412,8 +5418,14 @@ def cse(exprs):
     return (vec_pair_to_list(replacements), vec_basic_to_list(reduced_exprs))
 
 def latex(expr):
-    cdef Basic expr_ = sympify(expr)
-    return symengine.latex(deref(expr_.thisptr)).decode("utf-8")
+    cdef DenseMatrixBase mat_expr
+    cdef Basic basic_expr
+    if isinstance(expr, DenseMatrixBase):
+        mat_expr = expr
+        return symengine.latex(deref(symengine.static_cast_DenseMatrix(mat_expr.thisptr)), 20, 12).decode("utf-8")
+    else:
+        basic_expr = sympify(expr)
+        return symengine.latex(deref(basic_expr.thisptr)).decode("utf-8")
 
 cdef _flattened_vec(symengine.vec_basic &vec, exprs):
     cdef Basic b

symengine/tests/test_matrices.py

@@ -1,4 +1,4 @@
-from symengine import symbols
+from symengine import symbols, init_printing
 from symengine.lib.symengine_wrapper import (DenseMatrix, Symbol, Integer,
     Rational, function_symbol, I, NonSquareMatrixError, ShapeError, zeros,
     ones, eye, ImmutableMatrix)
@@ -725,3 +725,10 @@ def test_LUdecomp():
     for orig, new in p:
         res.row_swap(orig, new)
     assert res - testmat == zeros(4)
+
+def test_repr_latex():
+    testmat = DenseMatrix([[0, 2]])
+    init_printing(True)
+    latex_string = testmat._repr_latex_()
+    assert isinstance(latex_string, str)
+    init_printing(False)

symengine_version.txt

@@ -1 +1 @@
-v0.8.1
+23abf31763620463500d5fad114d855afd66d011