Hi, Split the calculation up an use echo to find the problem. David Rice wrote:
> Hi: > I am attempting to calculate a mortgage payment using the following code. > > <?PHP > $P = 100000; // principal outstanding > $I = 4.5; // annual interest rate percentage > $N = 20; // number of years > > // The formula that I am using > //(P*(((1+i/200)^(1/6)-1))/(1-(((1+i/200)^(1/6)))^-(n*12))) > > $Pmt = > $P*((pow(1+($I/200),(1/6))-1)/(1-pow(pow((1+$I/200),(1/6)),-($N*12)))); > > echo $Pmt; > ?> > > which produces: 630.40515566726 > > What I am looking for is 632.65 (rounded to 2 places). > > (I am not looking for a rounding mechanism, just a more accurate result) > The manual states that the pow function attempts to return an Integer. > Is this the source of the inaccurate result? > > The manual also says to look at exp but appears to be missing some > sort of usage example. I have no idea how that works. I tried a few > things with no success. > > I also came across a mention of bcpow() but am unable to use this in > the build that I am using. > > So is it some boneheaded coding error on my part or am I asking for > too much of pow()? > > Thanks > > David > > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
