Re: evaluating functions and displaying results numerically

*To*: mathgroup at smc.vnet.net*Subject*: [mg126166] Re: evaluating functions and displaying results numerically*From*: "djmpark" <djmpark at comcast.net>*Date*: Sun, 22 Apr 2012 06:07:02 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <13085423.12310.1334983918872.JavaMail.root@m06>

It's because Sin[1] is regarded by Mathematica as an exact expression. Mathematica can often do manipulations with exact expressions and obtain exact results. Mathematica does not convert then to approximate numbers until you use N on them, or mix them with approximate numbers. Sin[1] // N 0.841471 And remember that the purpose of N is to convert exact numbers to approximate numbers and not to format numbers. To format numbers for display use NumberForm. David Park djmpark at comcast.net http://home.comcast.net/~djmpark/index.html From: Eduardo Fontana [mailto:prof.eduardofontana at gmail.com] Once in a while a face a problem with Mathematica in which I cannot get a straightforward numerical output. I have a function defined in mathematica, I try to evaluate the function with numerical arguments and mathematica returns a replica of my function with the same arguments. It must be something I set without noticing. I cannot get numerical results at all. In another instance, I have a summation of about 1000 terms defined as a function of 3 arguments. When I use numerical arguments, instead of Mathematica calculating a numerical result it generates a symbolic output with all 1000 terms. Even if a try something very simple such as In[1]: Sin[1] the output is Out[1]: Sin[1] Could anyone give me a clue on this? regards