Re: Curious Timing Results
- To: mathgroup at smc.vnet.net
- Subject: [mg38663] Re: Curious Timing Results
- From: Bill Rowe <listuser at earthlink.net>
- Date: Sat, 4 Jan 2003 07:25:43 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
On 1/3/03 at 12:15 AM, grant at math.byu.edu (Chris Grant) wrote: >I find the Timing results below a little curious. Is there a simple >explanation why I shouldn't? >In[1]:= x = Table[2.,{i,100000}]; >In[2]:= y = Table[If[i<1000000,2.,i],{i,100000}]; >In[3]:= SameQ[x,y] >Out[3]= True Huh??? The last element of y should be 1000000 while the last element of x should be 2. >In[4]:= Timing[Inner[Divide,x,x]] >Out[4]= {0.44 Second,100000.} >In[5]:= Timing[Inner[Divide,y,y]] >Out[5]= {0.321 Second,100000.} Possibly the difference is because one is stored as a packed array and the other isn't. try Developer`PackedArrayQ[x] and Developer`PackedArrayQ[y]