Re: [sage-devel] Vector weirdness: to be or not to be immutable

2015-05-27 Thread David Joyner
On Wed, May 27, 2015 at 11:38 AM, Johan S. R. Nielsen wrote: > Hi Sage-devel > > We just crashed our heads against a bug in our code due to extremely weird > semantics of Sage. Consider the following code which creates a sub-space C > of the four-dimensional vector space over the binary field, and

Re: [sage-devel] Vector weirdness: to be or not to be immutable

2015-05-27 Thread Vincent Delecroix
On 27/05/15 17:38, Johan S. R. Nielsen wrote: Hi Sage-devel We just crashed our heads against a bug in our code due to extremely weird semantics of Sage. Consider the following code which creates a sub-space C of the four-dimensional vector space over the binary field, and then modifies a *copy*

[sage-devel] Vector weirdness: to be or not to be immutable

2015-05-27 Thread Johan S. R. Nielsen
Hi Sage-devel We just crashed our heads against a bug in our code due to extremely weird semantics of Sage. Consider the following code which creates a sub-space C of the four-dimensional vector space over the binary field, and then modifies a *copy* of a vector from the subspace: F = GF(2) VS