diff --git a/Base/Utils/MathFunctions.cpp b/Base/Utils/MathFunctions.cpp
index f01f622f305c04302ebeaadbab600ac09f589059..cf92b20107d785af49e8b4cdcd838a0e727fb2a6 100644
--- a/Base/Utils/MathFunctions.cpp
+++ b/Base/Utils/MathFunctions.cpp
@@ -51,11 +51,6 @@ double MathFunctions::cot(double x)
     return tan(M_PI_2 - x);
 }
 
-double MathFunctions::Si(double x) // int_0^x du Sin(u)/u
-{
-    return gsl_sf_Si(x);
-}
-
 double MathFunctions::sinc(double x) // Sin(x)/x
 {
     return gsl_sf_sinc(x / M_PI);
diff --git a/Base/Utils/MathFunctions.h b/Base/Utils/MathFunctions.h
index 727ae2c390f9d07c99178e81eb5e7e81b17b6802..291581999943d00b7fe0ca3e789a41d64b848f73 100644
--- a/Base/Utils/MathFunctions.h
+++ b/Base/Utils/MathFunctions.h
@@ -34,9 +34,6 @@ double IntegratedGaussian(double x, double average, double std_dev);
 //! cotangent function: \f$cot(x)\equiv1/tan(x)\f$
 double cot(double x);
 
-//! Sine integral function: \f$Si(x)\equiv\int_0^x du \sin(u)/u\f$
-double Si(double x);
-
 //! sinc function: \f$sinc(x)\equiv\sin(x)/x\f$
 double sinc(double x);
 
diff --git a/auto/Wrap/doxygenBase.i b/auto/Wrap/doxygenBase.i
index 04d4c0a481982acf192f85d509d43f123b5dc7a1..67110f8695246d8a0b098abcfa6cfcf819b24c1f 100644
--- a/auto/Wrap/doxygenBase.i
+++ b/auto/Wrap/doxygenBase.i
@@ -1275,11 +1275,6 @@ Forked from same source as for Bessel_J0_PowSer
 cotangent function:  $cot(x)\\\\equiv1/tan(x)$
 ";
 
-%feature("docstring")  MathFunctions::Si "double MathFunctions::Si(double x)
-
-Sine integral function:  $Si(x)\\\\equiv\\\\int_0^x du \\\\sin(u)/u$. 
-";
-
 %feature("docstring")  MathFunctions::sinc "double MathFunctions::sinc(double x)
 
 sinc function:  $sinc(x)\\\\equiv\\\\sin(x)/x$
diff --git a/auto/Wrap/libBornAgainBase.py b/auto/Wrap/libBornAgainBase.py
index c56b4dfa91bb2dd6d74547cdb1a04cb0856d83de..484e06d51ec520c37150f0d15c8e1bd023099aa8 100644
--- a/auto/Wrap/libBornAgainBase.py
+++ b/auto/Wrap/libBornAgainBase.py
@@ -1789,16 +1789,6 @@ def cot(x):
     """
     return _libBornAgainBase.cot(x)
 
-def Si(x):
-    r"""
-    Si(double x) -> double
-    double MathFunctions::Si(double x)
-
-    Sine integral function:  $Si(x)\\equiv\\int_0^x du \\sin(u)/u$. 
-
-    """
-    return _libBornAgainBase.Si(x)
-
 def sinc(*args):
     r"""
     sinc(double x) -> double
diff --git a/auto/Wrap/libBornAgainBase_wrap.cpp b/auto/Wrap/libBornAgainBase_wrap.cpp
index 559625f8d083a1aa30879a61d43e3ecf05410043..052a829cfdf054e6b69a328e4e59257384b05350 100644
--- a/auto/Wrap/libBornAgainBase_wrap.cpp
+++ b/auto/Wrap/libBornAgainBase_wrap.cpp
@@ -24457,29 +24457,6 @@ fail:
 }
 
 
-SWIGINTERN PyObject *_wrap_Si(PyObject *SWIGUNUSEDPARM(self), PyObject *args) {
-  PyObject *resultobj = 0;
-  double arg1 ;
-  double val1 ;
-  int ecode1 = 0 ;
-  PyObject *swig_obj[1] ;
-  double result;
-  
-  if (!args) SWIG_fail;
-  swig_obj[0] = args;
-  ecode1 = SWIG_AsVal_double(swig_obj[0], &val1);
-  if (!SWIG_IsOK(ecode1)) {
-    SWIG_exception_fail(SWIG_ArgError(ecode1), "in method '" "Si" "', argument " "1"" of type '" "double""'");
-  } 
-  arg1 = static_cast< double >(val1);
-  result = (double)MathFunctions::Si(arg1);
-  resultobj = SWIG_From_double(static_cast< double >(result));
-  return resultobj;
-fail:
-  return NULL;
-}
-
-
 SWIGINTERN PyObject *_wrap_sinc__SWIG_0(PyObject *SWIGUNUSEDPARM(self), Py_ssize_t nobjs, PyObject **swig_obj) {
   PyObject *resultobj = 0;
   double arg1 ;
@@ -33801,13 +33778,6 @@ static PyMethodDef SwigMethods[] = {
 		"cotangent function:  $cot(x)\\\\equiv1/tan(x)$\n"
 		"\n"
 		""},
-	 { "Si", _wrap_Si, METH_O, "\n"
-		"Si(double x) -> double\n"
-		"double MathFunctions::Si(double x)\n"
-		"\n"
-		"Sine integral function:  $Si(x)\\\\equiv\\\\int_0^x du \\\\sin(u)/u$. \n"
-		"\n"
-		""},
 	 { "sinc", _wrap_sinc, METH_VARARGS, "\n"
 		"sinc(double x) -> double\n"
 		"sinc(complex_t const z) -> complex_t\n"