3.9 amstex

<..configure picmath0 amstex..>
 \:CheckOption{no-matrix} \if:Option \else
 \:CheckOption{pic-matrix}   \if:Option
       <.pic amstex.tex matrix 0.0.>
 \else
       <.tabular amstex.tex matrix 0.0.>
 \fi\fi
 \:CheckOption{no-align} \if:Option \else
 \:CheckOption{pic-align}   \if:Option
       <.pic amstex.tex align 0.0.>
 \else
       <.tabular amstex.tex align 0.0.>
 \fi\fi
-_-_-

Do we need the following? Don’t those of plain.sty are good here?

<..pic amstex.tex matrix 0.0..>
 \Configure{matrix}{}{}
-_-_-

<..pic amstex.tex matrix 0.0..>+
 \Configure{pmatrix}{}{}
-_-_-

<..tabular amstex.tex matrix 0.0..>
 \Configure{matrix}{}{}{}{}{}{}
-_-_-

<..tabular amstex.tex matrix 0.0..>+
 \Configure{pmatrix}{}{}
-_-_-