maxima - Terms of an equation in different order -


i'm using wxmaxima 15.08.1 (win 10) , when input equation

/* [wxmaxima: input   start ] */a*x+b*y+c*z=0;

i this:

/* [wxmaxima: input   end   ] */cz+by+ax=0

why change term's position of expression? seems in descending order somehow.

then, if type equation giving coefficients same unknown, maxima outputs right.

/* [wxmaxima: input   start ] */a*x^2+b*x+c=0;  /* [wxmaxima: input   end   ] */ax^2+bx+x=0

maxima has own idea of canonical ordering of terms in "+" , "*" expressions. canonical ordering expressed function ordergreatp (equivalently orderlessp) tells if 1 term comes after (respectively, before) term. if apply sort list of terms, sorted, default, according canonical order.

by default, "+" terms displayed in reverse order (reverse of canonical order). when global variable powerdisp true, "+" terms displayed in canonical order. can decide whether 1 order or other works better you.

(%i2) powerdisp; (%o2)                         false (%i3) a*x + b*y + c*z; (%o3)                    c z + b y + x (%i4) a*x^2 + b*x + c;                             2 (%o4)                    x  + b x + c  (%i7) powerdisp : true $ (%i8) a*x + b*y + c*z; (%o8)                    x + b y + c z (%i9) a*x^2 + b*x + c;                                       2 (%o9)                    c + b x + x

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