Re: in a loop
- To: mathgroup at smc.vnet.net
- Subject: [mg111859] Re: in a loop
- From: Helen Read <hpr at together.net>
- Date: Sun, 15 Aug 2010 07:39:56 -0400 (EDT)
- References: <i45rgj$g4u$1@smc.vnet.net>
- Reply-to: HPR <read at math.uvm.edu>
On 8/14/2010 6:34 AM, Bill Rowe wrote: > > For loops return Null. So, unless you specifically arrange for > an output by using Print or something equivalent, no output is > ever returned by a For loop. > > That is > > For[i = 0, i< 5, i++; i] > > will return nothing for exactly the same reason. > > One other observation, the listing created by > > dirnames = Names["$*Directory*"]; > For[i = 0, i< Length[dirnames],i++; Print[dirnames[[i]]]] > > is more created by > > ColumnForm[Names["$*Directory*"]] > > or > > TableForm[Names["$*Directory*"]] > > which seems to me a simpler more direct approach than using > Print in a For loop. These methods are also more efficient as > there is no need to compute the number of items and increment an > indexing variable. Even simpler: Column[Names["$*Directory*"]] Ever since Grid and Column were introduced, I find no need for TableForm anymore. -- Helen Read University of Vermont