On 10/1/12 2:40 AM, Justin C. Walker wrote:
On Oct 1, 2012, at 00:28 , Santanu Sarkar wrote:I have written the following: T=[0]*2 S=[] l=2 for i in range(l): T[0]=i T[1]=i+1 print T S.append(T) Now S becomes [[1, 2], [1, 2]] instead of [[0,1],[1,2]]. In my situation, length l of S is not fixed. Is there any method to solve this problem?This is the result of a feature of the Python language. 'T' is the name of an array, and acts like its address, so as you append T to S, you are continually reusing that same address. When you update the elements in T (by, e.g., "T[0]=i"), you are modifying the content of T. To avoid this, you could do something like S=[] l=2 for i in range(l): print T S.append([i,i+1])
For this example, you don't even really need T: l=2 S = [[i,i+1] for i in range(l)] Jason -- You received this message because you are subscribed to the Google Groups "sage-support" group. To post to this group, send email to sage-support@googlegroups.com. To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support?hl=en.
