code: def test_CXX17CodePrinter():
      assert CXX17CodePrinter().doprint(beta(x, y)) == "std::beta(x, y)"
      assert CXX17CodePrinter().doprint(Ei(x)) == "std::expint(x)"
      assert (
          CXX17CodePrinter().doprint(zeta(x)) == "std::riemann_zeta(x)"
      )
  
      # Automatic rewrite
      assert (
          CXX17CodePrinter().doprint(frac(x)) == "(x - std::floor(x))"
      )
      assert (
          CXX17CodePrinter().doprint(riemann_xi(x))
          == "((1.0/2.0)*std::pow(M_PI, -1.0/2.0*x)*x*(x - 1)*std::tgamma((1.0/2.0)*x)*std::riemann_zeta(x))"
      )
  
file_path: sympy/sympy/printing/tests/test_cxx.py
imports: from sympy.core.numbers import Float, Integer, Rational
  from sympy.core.symbol import symbols
  from sympy.functions import beta, Ei, zeta, Max, Min, sqrt, riemann_xi, frac
  from sympy.printing.cxx import CXX98CodePrinter, CXX11CodePrinter, CXX17CodePrinter, cxxcode
  from sympy.codegen.cfunctions import log1p
label_desc: Use image node_id 5 for calling a global function with example usage: test_CXX17CodePrinter() without return types