MathGroup Archive 2013

[Date Index] [Thread Index] [Author Index]

Search the Archive

Function with optional default argument cannot cache results


Is there a discussion somewhere on why this is?

In[1]:= $Version
f[x_, y_: 2] := f[x, y] = {Pause[1], x, y}
f[1, 2] // AbsoluteTiming
f[1, 2] // AbsoluteTiming
f[1] // AbsoluteTiming
f[1] // AbsoluteTiming

Out[1]= "9.0 for Microsoft Windows (64-bit) (January 25, 2013)"

Out[3]= {1.014002, {Null, 1, 2}}

Out[4]= {0., {Null, 1, 2}}

Out[5]= {1.029602, {Null, 1, 2}}

Out[6]= {1.014002, {Null, 1, 2}}



  • Prev by Date: Re: Does Wolfram Alpha Pro support all of the functionality of Mathematica
  • Next by Date: Re: NMF in Mathematica 8
  • Previous by thread: Re: Does Wolfram Alpha Pro support all of the functionality of Mathematica
  • Next by thread: Re: Function with optional default argument cannot cache