# [Scilab-users] == and : relative priorities, as in 0==-1:1

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## [Scilab-users] == and : relative priorities, as in 0==-1:1

 Hello, Here is a strange -- rather unexpected -- trivial behavior: --> p = 0; p==-1:1 Undefined operation for the given operands. check or define function %b_b_s for overloading. I would have expected [%f %t %f], but "==" 's priority is higher than ":"'s one, and the expression is parsed (p==-1):1. It's the same with other comparisons, like p>-1:1. It was the same behavior in Scilab 5.5.2. Since by default ":" is defined and meaningful for a very limited set of operands types: numbers and text (, and that ":" does not accept a vector as  operands), what about inverting the comparisons and ":" relative priorities, in order to parse p==(-1:1) ? "~" and comparisons relative priorities are inverted in Scilab 6. That's more handy. IMO here is another opportunity get a more relevant and handy behavior, by inverting ":" and comparisons ones. Don't you think so? Regards Samuel _______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users
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## Re: == and : relative priorities, as in 0==-1:1

 Le 31/07/2018 à 21:51, Samuel Gougeon a écrit : Hello, Here is a strange -- rather unexpected -- trivial behavior: --> p = 0; p==-1:1 Undefined operation for the given operands. check or define function %b_b_s for overloading. I would have expected [%f %t %f], but "==" 's priority is higher than ":"'s one, and the expression is parsed (p==-1):1. It's the same with other comparisons, like p>-1:1. It was the same behavior in Scilab 5.5.2. Since by default ":" is defined and meaningful for a very limited set of operands types: numbers and text (, and that ":" does not accept a vector as  operands), what about inverting the comparisons and ":" relative priorities, in order to parse p==(-1:1) ? "~" and comparisons relative priorities are inverted in Scilab 6. That's more handy. IMO here is another opportunity get a more relevant and handy behavior, by inverting ":" and comparisons ones. It is somewhat reported here (in 2011..), but i don't understand the conclusion of the report... _______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users
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## Re: == and : relative priorities, as in 0==-1:1

 In reply to this post by Samuel GOUGEON Hi Samuel,   Parsing p==-1:1 as  p==(-1:1) would make Scilab output: ans  =   F T F   consistent with Matlab: ans =    1x3 logical array    0   1   0   And with Octave: ans =   0  1  0   Regards, Rafael   From: users <[hidden email]> On Behalf Of Samuel Gougeon Sent: Tuesday, July 31, 2018 9:52 PM To: International users mailing list for Scilab. <[hidden email]> Subject: [Scilab-users] == and : relative priorities, as in 0==-1:1   Hello, Here is a strange -- rather unexpected -- trivial behavior: --> p = 0; p==-1:1 Undefined operation for the given operands. check or define function %b_b_s for overloading. I would have expected [%f %t %f], but "==" 's priority is higher than ":"'s one, and the expression is parsed (p==-1):1. It's the same with other comparisons, like p>-1:1. It was the same behavior in Scilab 5.5.2. Since by default ":" is defined and meaningful for a very limited set of operands types: numbers and text (, and that ":" does not accept a vector as  operands), what about inverting the comparisons and ":" relative priorities, in order to parse p==(-1:1) ? "~" and comparisons relative priorities are inverted in Scilab 6. That's more handy. IMO here is another opportunity get a more relevant and handy behavior, by inverting ":" and comparisons ones. Don't you think so? Regards Samuel _______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users
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## Re: == and : relative priorities, as in 0==-1:1

 In reply to this post by Samuel GOUGEON Le 31/07/2018 à 21:51, Samuel Gougeon a écrit : It is somewhat reported here (in 2011..), but i don't understand the conclusion of the report...  : “It seems that "he who must not be named" has different priorities on operators.”                    Is Voldemort working in the Scilab team? _______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users
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## Re: == and : relative priorities, as in 0==-1:1

 Haha, I was referring to Matlab. It was a private joke with Bruno. Sorry about for misunderstanding. Antoine Le 31/07/2018 à 22:20, Rafael Guerra a écrit : Le 31/07/2018 à 21:51, Samuel Gougeon a écrit : It is somewhat reported here (in 2011..), but i don't understand the conclusion of the report...  : “It seems that "he who must not be named" has different priorities on operators.”                    Is Voldemort working in the Scilab team? ```_______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users ``` _______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users