I seem to have created a riot on this thread; now let me mediate.
Actually you haven't. It is perfectly OK to have discussions and exhibit different opinions. It is also perfectly OK to expose factual errors in the reasoning of others. (Who would know that better than me who has been - rightfully - corrected over and over again here, most oftenly by Don Cragun.)
Quote:
Originally Posted by wisecracker
Firstly I did quote using "INTEGER arithmetic".
Secondly I also quoted "it is a little tongue-in-cheek".
And thirdly it uses builtins only...
I think that, even restricting yourself to integer arithmetic and built-ins, you could speed up the process by using better algorithms. For instance, an application of Newtons method of caluclating the roots of differentiable functions (also called "Netwon-Raphson-method):
Suppose some real function f: [a,b] -> R, which is differentiable everywhere on the intervall [a,b] with values only in R.
It can easily be shown that, starting from an initial guess x[n] (as long as x[n] is reasonably close to x), a better guess x[n+1] can be calculated using the formula
by solving for the tangents equation at f(x)=y and then solving for the x-intercept of this line (Simpsons approximation).
Applying this to get the zeroes of the iteration function f(x) = x**2 - a brings us to the "babylonian method" or "Heron's method" of calculating roots:
Because of the deriative f'(x) = 2x for the solution sqrt(a) we get the approximation
by which we calculate a series of xi's (i=0,1,2,...), which will converge against x, until a sufficient approximation is reached.
Quote:
Originally Posted by wisecracker
One very serious question however:-
How accurate is either "[?]awk's" or "ksh's" floating point?
Hi All,
I have a file of the following format.
<?xml version='1.0' encoding='utf-8'?>
<tomcat-users>
<role rolename="tomcat"/>
<role rolename="role1"/>
<role rolename="manager"/>
<role rolename="admin"/>
<user username="tomcat" password="tomcat" roles="tomcat"/>
<user... (5 Replies)
Here's my work of testing whether a number input is perfect or not..
echo Enter a number
read no
i=1
ans=0
while
do
if
then
ans='expr $ans + $i'
fi
i='expr $i + 1'
done
if
then
echo $no is perfect
else
echo $no is NOT perfect
fi (12 Replies)
I've got an aix-box somewhere on the network and a PC on my desk. Nothing fancy so far.
The PC is made dual-boot:
- windowsXP with putty & winSCP
or
- slackware 13 with xfce4 installed.
The aix-box runs DB2 v8.2 and I've installed db2top to monitor the database.
db2top is a character... (0 Replies)
Hi All,
I have a text file which looks like this:
computer programming
systems engineering
I want to get rid of these square brackets and also the text that is inside these brackets. So that my final text file looks like this:
computer programming
systems engineering
I am using... (3 Replies)
I want to print only the lines that meet the criteria : "worde:" and "wordo;"
I got this far:
sed -n '/\(*\)\1e:\1o;/p;'
But it doesn't quite work.
Can someone please perfect it and tell me exactly how its a fixed version/what was wrong with mine?
Thanks heaps, (1 Reply)
I have to find last delimiter in each line of a file and store the value after the last '/' in a variable in ksh script...Pls Pls help me:(The file is as shown below:
/opt/apps/cobqa/apps/abadv/bind/advc0007.bnd
/opt/apps/cobqa/apps/abbrio/bind/naac6115.bnd... (5 Replies)