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Re: V6 evaluation inside Table and plot


Hi,

and

Table[Evaluate[f''[x]], {x, 0, 1, .2}]

works as well as

Table[Evaluate[f'[x]], {x, 0, 1, .2}]

Regards
   Jens

Gerry Flanagan wrote:
> Define a simple function
> 
> In[7]:= f = Function[{x}, x^3]
> 
> Out[7]= Function[{x}, x^3]
> 
> Taking two derivatives works as it should
> 
> In[2]:= f''[x]
> 
> I was converting some packages to work with V6, and immediately ran into 
> some evaluation issues I don't understand. It looks like forms like 
> f''[x] (derivative) are evaluated differently inside of Table and Plot 
> than outside.
> 
> Out[2]= 6 x
> 
> But this does not?
> 
> In[20]:= Table[f''[x], {x, 0, 1, .2}]
> 
> Out[20]= {0, 0, 0, 0, 0, 0}
> 
> Strangely, this works
> 
> In[4]:= Table[f'[x], {x, 0, 1, .2}]
> 
> Out[4]= {0., 0.12, 0.48, 1.08, 1.92, 3.}
> 
> Determining the derivative outside the Table makes it work again.
> 
> In[12]:= g = f'';
> 
> In[21]:= tmp = Table[g[x], {x, 0, 1, .2}]
> 
> Out[21]= {0., 1.2, 2.4, 3.6, 4.8, 6.}
> 
> Gerry Flanagan
> 


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