Re: What is going on!?!
- To: mathgroup at smc.vnet.net
- Subject: [mg104763] Re: What is going on!?!
- From: Albert Retey <awnl at gmx-topmail.de>
- Date: Sun, 8 Nov 2009 07:27:19 -0500 (EST)
- References: <hd3ml1$9in$1@smc.vnet.net>
Joe Hays schrieb: > 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 you are multiplying the result of the For loop with x, which happens to be 10. And from the documentation: "Unless an explicit Return is used, the value returned by For is Null." which is why the result of the loop times 10 is 10*Null... hth, albert