Dear Sirs

If I tried:

\starttext
\startluacode
sample = {10,30,30,40}

 function MP.GetP()
 mp.print(sample)
 end
\stopluacode

\startMPcode
draw lmt_chart_bar [
 width = 8cm,
 height = 10mm,
 samples = {lua.MP.GetP()} ,
 trace = true,
 maximum = 100,
 linewidth = 1mm,
 showlabels = false,
 originsize = 0,
 labelanchor = "lft",
 labelcolor = "black"
 labelstyle = "bfxx"
 legendstyle = "tfxx",
 labelstrut = "yes",
] ;
\stopMPcode

\stoptext

This works.

But with an extra element in the sample table:

\starttext
\startluacode
sample = {10,30,30,40,50}

 function MP.GetP()
 mp.print(sample)
 end
\stopluacode

\startMPcode
draw lmt_chart_bar [
 width = 8cm,
 height = 10mm,
 samples = {lua.MP.GetP()} ,
 trace = true,
 maximum = 100,
 linewidth = 1mm,
 showlabels = false,
 originsize = 0,
 labelanchor = "lft",
 labelcolor = "black"
 labelstyle = "bfxx"
 legendstyle = "tfxx",
 labelstrut = "yes",
] ;
\stopMPcode

\stoptext

Don't works anymore. Why?

Thanks for your time and support.