!set methtit=交换方程的两边
!set methparmtype=parm equation
!set methhelp=此方法把方程 \(a = b) 重写成 \(b = a).

!if $wims_read_parm iswordof form check
 !goto $wims_read_parm
!endif

!exit
:form
 交换以下方程的两边
 !read deduc/methparm.phtml 1

!exit
:check
 !distribute items $methparmobj1 into data,left,sign,right
 methexp=交换 \($left $sign $right) 的两边

 newobject1=$right $sign $left
 oldobject=1

 contextlist=$ct_Always,\
    $ct_Onlywhen两边是正的,\
    $ct_Onlywhen两边同号

!exit

