Re: Numerical Evaluation

*To*: mathgroup at smc.vnet.net*Subject*: [mg85630] Re: Numerical Evaluation*From*: Bill Rowe <readnewsciv at sbcglobal.net>*Date*: Sat, 16 Feb 2008 03:28:59 -0500 (EST)

On 2/14/08 at 6:51 PM, dmoran21 at cox.net (David Moran) wrote: >Hi, I need to know what the best way to do this is. I have a >function and I want to evaluate a derivative (not necessarily the >first derivative) of the function. What is the best way to do this? Is there a problem with using the built in operator D? For example, a second derivative is computed as follows: In[1]:= D[x^3 + x Sin[x], {x, 2}] Out[1]= -sin(x) x+6 x+2 cos(x) And this can be used to give a numerical result by simply using a replacement rule, i.e., for x = 2.5 the result is: In[2]:= D[x^3 + x Sin[x], {x, 2}] /. x -> 2.5 Out[2]= 11.9015 -- To reply via email subtract one hundred and four