Re: What is going on!?!
- To: mathgroup at smc.vnet.net
- Subject: [mg104759] Re: What is going on!?!
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Sun, 8 Nov 2009 06:52:10 -0500 (EST)
On 11/7/09 at 6:46 AM, joehays at vt.edu (Joe Hays) wrote:
>Can anyone tell me why the output is not a simple "10" instead of
>"10 Null"?
>In[3]:= x = 0; For[i = 1, i <= 10, i++,
>x = x + 1;
>]x
>Out[4]= 10 Null
Per the documentation, For returns Null. So For[....] x
evaluates to x times Null which is what you got. If you want
simply the result then change the code to be:
=46or[i = 1, i <= 10, i++,
x = x + 1;
]; x
Or even better
Sum[n,,{n,10}]