# [Scilab-users] bug in degree and polynomials comparison ?

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## [Scilab-users] bug in degree and polynomials comparison ?

 Hi, while upgrading one of my toolboxes I discovered a strange error in polynomial comparisons. The error appeared during automatic unit tests, a " assert_checkequal(P1,P2)" was expected to be True and was in fact False. After some investigations It looks like there is an error in degree so that   P1==P2 can be False  while  P1-P2==0. Can someone confirm the bug in scilab-6.0.1  before I fill in a report on bugzilla. Run the following commands : X=poly(0,'x') A=(X-1)^3 B=(X+1)^2 R=20 +12*X Q=(A-R*X^3)/B; Q=Q.num A,(B*Q+R*X^3) // equal A-(B*Q+R*X^3)  //=0 A==(B*Q+R*X^3)  // %F !!!! coeff((B*Q+R*X^3)) coeff(A) degree((B*Q+R*X^3)) // =4 !! degree(A)  // = 3 and compare with the expected result thereafter Sincerly yours, Philippe --> A,B,Q,R  A  =             2   3   -1 +3x -3x  +x  B  =            2    1 +2x +x  Q  =              2   -1 +5x -12x  R  =    20 +12x --> A,(B*Q+R*X^3)  A  =             2   3   -1 +3x -3x  +x  ans  =             2   3   -1 +3x -3x  +x --> A-(B*Q+R*X^3)  ans  =    0 --> A==(B*Q+R*X^3)  ans  =   F --> coeff((B*Q+R*X^3))  ans  =   -1.   3.  -3.   1.   0. --> coeff(A)  ans  =   -1.   3.  -3.   1. --> degree((B*Q+R*X^3))  ans  =    4. --> degree(A)  ans  =    3. _______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users