\startsubformulas[eq:total]
\startplaceformula
\startformula
\startalign
\stopformula
\stopsubformulas
\stopplaceformula
Formula \eqref[eq:total] states the Pythagora's Theorem twice,
You can compare without \tex{startsubformulas}:
\placeformulastartplaceformula
\startformula
\startalign
\stopalign
\stopformula
\stopplaceformula
We now have references for \eqref[eq2:first] and \eqref[eq2:second].
</context>
= Combination of formulae with {{cmd|startformulas}} =
To use subformula numbering, you have to use {{cmd|startsubformulas}}/{{cmd|stopsubformulas}} and {{cmd|startalign}}. For example
<context source="yes" text="This, when typeset, produces the following:">
\definereferenceformat[eqref][left=(,right=)]
The famous result (once more) is given by
\startsubformulas[eq:total]
\startplaceformula
\startformulas
\startformula
\startalign
\NC a^2 + b^2 \NC = c^2 \NR[eq:first]
\NC a^2 + b^2 \NC = c^2 \NR[eq:second]
\stopalign
\stopformula
\startformula
\startalign
\NC a^2 + b^2 \NC = c^2 \NR[eq:third]
\NC a^2 + b^2 \NC = c^2 \NR[eq:forth]
\stopalign
\stopformula
\stopformulas
\stopplaceformula
\stopsubformulas
We now have references for \eqref[eq:forth] for example.
</context>