sansmath functionality with fontspec

Question

I always typeset bar plots (using the pgfplots package that uses math-mode for pgfplots labeling) with a sans serif font. Since I'm using LuaTeX I'm running into problems (see also Bar plots in sans serif font where I described the same problem). With PDFTeX the sansmath package and @sebschub's MyriadPro files solve the problem. But I can't get to implement those functionalities with fontspec. How can I typeset pgfplots bar plots with LuaTeX/fontspec?

Here's a MWE with the fonts I use (MinionPro and MyriadPro that ship with Adobe Reader):

\documentclass{scrartcl}
\usepackage{%
  sansmath%
} 
\usepackage{fontspec}
\setmainfont[%
  BoldFont={MinionPro-Bold}%
  ,ItalicFont={MinionPro-It}%
  ,BoldItalicFont={MinionPro-BoldIt}%
  ,Numbers=OldStyle%
]{MinionPro-Regular}

\setsansfont[%
  Scale=MatchLowercase%
  ,BoldFont={MyriadPro-Bold}%
  ,ItalicFont={MyriadPro-It}%
  ,BoldItalicFont={MyriadPro-BoldIt}%
  ,Numbers=OldStyle%
]{MyriadPro-Regular}
\setmathsf{MyriadPro-Regular}
\usepackage{pgfplots}
\pgfplotsset{%
  /tikz/font=\sansmath\sffamily
}
\usepackage{filecontents}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
  xbar,
  xlabel={a--d},
  symbolic y coords={a,b,c,d},
  ytick=data,
  nodes near coords, nodes near coords align={horizontal},
  ]
  \addplot coordinates {
    (45,a)
    (20,b)
    (1,c)
    (5,d)
    };
\end{axis}
\end{tikzpicture}
\end{document}

Here's the corresponding plot (I don't want italic fonts):

Here are some of the pgfplotsset options I already tried (and noted down):

\pgfplotsset{%
%  ,tick label style = {font=\sansmath\sffamily}%
%  ,tick style = {font=\sansmath\sffamily}
%  ,every axis label = {font=\sansmath\sffamily}%
%  ,every axis/.style={font=\sansmath\sffamily}%
%  ,xticklabel={$\pgfmathprintnumber{\sansmath\tick}$}%
  ,/tikz/font=\sansmath\sffamily
%  ,legend style = {font=\sansmath\sffamily}%
%  ,label style = {font=\sansmath\sffamily}%
}

If you know a better place to ask this question let me know, please. TIA

Answer 1

here is a solution without using package sansmath

\documentclass{scrartcl}
\usepackage{unicode-math}
\setmainfont[%
  BoldFont={MinionPro-Bold}%
  ,ItalicFont={MinionPro-It}%
  ,BoldItalicFont={MinionPro-BoldIt}%
  ,Numbers=OldStyle%
]{MinionPro-Regular}
\setsansfont[%
  Scale=MatchLowercase%
  ,BoldFont={MyriadPro-Bold}%
  ,ItalicFont={MyriadPro-It}%
  ,BoldItalicFont={MyriadPro-BoldIt}%
  ,Numbers=OldStyle%
]{MyriadPro-Regular}  
\setmathfont{MyriadPro-Regular}
\usepackage{pgfplots}
\usepackage{filecontents}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
  xbar,
  xlabel={a--d},
  symbolic y coords={a,b,c,d},
  ytick=data,
  nodes near coords, nodes near coords align={horizontal},
  ]
  \addplot coordinates {
    (45,a)
    (20,b)
    (1,c)
    (5,d)
    };
\end{axis}
\end{tikzpicture}
\end{document}

Answer 2

If all of sansmath you need is printing numbers in the sans serif typeface and not general math expressions, here's a hack:

\documentclass{scrartcl}

\usepackage{fontspec}
\setmainfont[Ligatures=TeX,
  Numbers=OldStyle,
]{Minion Pro}

\setsansfont[Ligatures=TeX,
  Scale=MatchLowercase,
]{Myriad Pro}
\usepackage{pgfplots}
\pgfplotsset{%
  /tikz/font=\plotsf
}

\newfam\plotsffam
\newcommand\plotsf{%
  \sffamily
  \everymath{%
    \textfont\plotsffam=\usesf
    \mathcode`0=\numexpr 256*\plotsffam+`0\relax
    \mathcode`1=\numexpr 256*\plotsffam+`1\relax
    \mathcode`2=\numexpr 256*\plotsffam+`2\relax
    \mathcode`3=\numexpr 256*\plotsffam+`3\relax
    \mathcode`4=\numexpr 256*\plotsffam+`4\relax
    \mathcode`5=\numexpr 256*\plotsffam+`5\relax
    \mathcode`6=\numexpr 256*\plotsffam+`6\relax
    \mathcode`7=\numexpr 256*\plotsffam+`7\relax
    \mathcode`8=\numexpr 256*\plotsffam+`8\relax
    \mathcode`9=\numexpr 256*\plotsffam+`9\relax
  }%
}
\AtBeginDocument{{\sffamily\xdef\usesf{\the\font}}}

\begin{document}

\begin{tikzpicture}
\begin{axis}[
  xbar,
  xlabel={a--d},
  symbolic y coords={a,b,c,d},
  ytick=data,
  nodes near coords, nodes near coords align={horizontal},
  ]
  \addplot coordinates {
    (45,a)
    (20,b)
    (1,c)
    (5,d)
    };
\end{axis}
\end{tikzpicture}
\end{document}

The idea is to change the mathcode of the digits to choose the right typeface.