
Re: Mathematica and Lisp
Posted:
Mar 7, 2013 3:58 AM


On 3/6/2013 4:54 AM, Bill Rowe wrote:
> But > if I had a variable mylist set to {x,y,z}, then I would either > code the sum as Plus@@myList or Total@myList or Total[myList] > > Similarly if I myMatrix were a n x m array and I wanted to > compute the sum of each row, I might well code this as Plus@@@myMatrix. >
Nice examples.
I do not use @@@ myself. But interesting that the use of Total in the matrix case does not follow the example from the list case:
 OK  myList = {1, 2, 3}; Plus @@ myList Total @ myList 
So, I thought it should then work the same for matrix, I should remove one "@" for Total compared to the Plus case
Not OK  myList = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}} Plus @@@ myList Total @@ myList 
I need to look more into this to see why it did not follow the same example for list.
Nasser

