Aaron Fude wrote:
> I can't figure out how the precision and accuracy concepts work in
> Mathematica.
There are all about *uncertainty*.
<snip>
> C. On a related issue, how do I see Pi to a certain number of digits.
> I figured out this hack:
>
> 1``100 Pi
In[1]:= N[Pi, 30]
Out[1]= 3.14159265358979323846264338328
> D. And finally (for now) where can I read up on rules for "precision
> arithmetic". For example, my guess that
>
> Precision[1`10 + 1`100]
>
> ought to be 100-ish rather than 10-ish.
You must have studied some physics and/or chemistry. Do you remember the
first few classes? Some time must have been devoted to the topic of
measurements and uncertainties. Similar concepts applied here.
Say you are given two documents: one reports than person A is 180 m +/-
1 cm tall, the other reports than person B is 180.5 +/- 0.1 cm tall. Can
you tell who is the tallest (and why it is so)?
If you can answer â correctly! â the above question, you can easily
apply the same line of though to numbers and precision in Mathematica.
Also, the following set of short tutorials is a must read.
"Numbers", tutorial/NumbersOverview,
http://reference.wolfram.com/mathematica/tutorial/NumbersOverview.html Types of Numbers
Numeric Quantities
Digits in Numbers
Numerical Precision
Arbitrary-Precision Numbers
Machine-Precision Numbers
Interval Arithmetic
Indeterminate and Infinite Results
Controlling Numerical Evaluation
Regards,
-- Jean-Marc
