OK after some reading let's see if my understanding is correct. Python variables are actually "identifiers" that sort of point to objects. In my example, i and j bind with the 2 inputs (symbol or integer) of KroneckerDelta. Even though I reassign i and j to different values, the actual inputs stay unchanged. Is this correct? If so, how should I change them?
Bi Ge On Sunday, March 3, 2013 1:23:44 PM UTC-5, Stefan Krastanov wrote: > > I do not think that the problem here is with your understanding of > sympy but rather with the way that pythonic variables work. > > for instance: > > L = [1,2] > a = L[0] # 'a' points to the object int(1) > a = 5 # 'L' does not change but 'a' points to the object int(5) > > I used the verb "points" but it would be wrong to say that python > variables are pointers. Checkout python's docs and search > stackoverflow for questions on this subject. > > > PS > And be aware that > > L[i] = var > > is a syntactic sugar for a method call, something quite different from > > a = var > > On 3 March 2013 04:52, Bi Ge <sean...@gmail.com <javascript:>> wrote: > > Hi Sympy community, > > > > I've been looking at issue3479 and trying to fix it by using minlex. > > Right now I just put the following at the end of def eval(cls, i, j): > > sort_args = minlex( ( i , j ) ) > > i = sort_args[0] > > j = sort_args[1] > > > > However, it still gives me the unchanged result such as: > >>>>KroneckerDelta(n, m) > > KroneckerDelta(n, m) > > > >>>>KroneckerDelta(m, n) > > KroneckerDelta(m, n) > > > > I guess I still don't fully understand how symbols work in this > function. > > Any help will be appreciated. > > > > Regards, > > > > Bi Ge > > > > -- > > You received this message because you are subscribed to the Google > Groups > > "sympy" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to sympy+un...@googlegroups.com <javascript:>. > > To post to this group, send email to sy...@googlegroups.com<javascript:>. > > > Visit this group at http://groups.google.com/group/sympy?hl=en. > > For more options, visit https://groups.google.com/groups/opt_out. > > > > > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at http://groups.google.com/group/sympy?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
