to_f for RealMPFR

Author: rajithv

ext/symengine/ruby_real_mpfr.c

@@ -1,6 +1,7 @@
 #include "ruby_real_mpfr.h"
 
-VALUE crealmpfr_init(VALUE self, VALUE num_value, VALUE prec_value) {
+VALUE crealmpfr_init(VALUE self, VALUE num_value, VALUE prec_value)
+{
     basic_struct *cresult;
     double d;
     char *c;
@@ -32,3 +33,16 @@ VALUE crealmpfr_init(VALUE self, VALUE num_value, VALUE prec_value) {
     return self;
 }
 
+VALUE crealmpfr_to_float(VALUE self)
+{
+    VALUE result;
+    basic cbasic_operand1;
+    basic_new_stack(cbasic_operand1);
+    sympify(self, cbasic_operand1);
+    
+    result = rb_float_new(real_mpfr_get_d(cbasic_operand1));
+
+    basic_free_stack(cbasic_operand1);
+    return result;
+}
+

ext/symengine/ruby_real_mpfr.h

@@ -8,5 +8,6 @@
 #include "symengine_utils.h"
 
 VALUE crealmpfr_init(VALUE self, VALUE num_value, VALUE prec_value);
+VALUE crealmpfr_to_float(VALUE self);
 
 #endif //RUBY_REAL_MPFR_H_

ext/symengine/symengine.c

@@ -90,6 +90,7 @@ void Init_symengine() {
     c_real_mpfr = rb_define_class_under(m_symengine, "RealMPFR", c_basic);
     rb_define_alloc_func(c_real_mpfr, cbasic_alloc);
     rb_define_method(c_real_mpfr, "initialize", crealmpfr_init, 2);
+    rb_define_method(c_real_mpfr, "to_f", crealmpfr_to_float, 0);
 
     //ComplexMPC class
     c_complex_mpc = rb_define_class_under(m_symengine, "ComplexMPC", c_basic);