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charco
31 Jul 2006, 05:53 AM
Hi folks - I'm a bit of a novato with JS and have written some science calculations programs using Avogador's number 6.02e23.
The problem is that when I set a variable to this number and then perform calculations with it it returns the "invalid floating point" error warning (and the computer crashes!)
However, this doesn't happen on the HTML version of the pages - only on the e-book that I am compiling using the html (I am using ebook edit pro)

The calculations I am using are fairly simple, as follows:

//initialise variables------------
attempts=0
total=0
correct=0
tried=0
avo=6.02E23
ans=""
RMMs=new Array(18,44,28,80,32,28,17,256,58.5,167,188,40,56,208,62)

function begin(){
n=Math.round(14*Math.random())
RMM=RMMs[n]
mass=Math.round(4*Math.pow(10,Math.random()))/100
Vg=Math.round(4*Math.pow(10,Math.random()))/100
moles=mass/RMM
display()
}

function display(){
dimV=" cm<sup>3</sup>"
dimM=" g"
dimV2=" dm<sup>3</sup>"

var h=Math.round(2.5*Math.random())
if(n<8){
h=0
}
if(n>7){
h=2
}

if(h==0){
v1=Vg+dimV
v2=mass+dimM
ans=moles*avo
}
if(h==1){
v1=Vg+dimV
v2=mass+dimM
ans=moles*avo
}
if(h==2 & n>7 & n<13){
v1=Vg+dimV
v2=mass+dimM
ans=moles*avo
ans=2*ans
}
if(h==2 & n>12){
v1=Vg+dimV
v2=mass+dimM
ans=moles*avo
ans=3*ans
}
ans=ans.toPrecision(3)
setthequestion()
}

and then I have to functions to set the question and show the answers. If I set the variable 'avo' to simple numbers the script has no problems but as it is a very large number 6.02 x 10(23) this causes the system to register the error.

My question is simple - is there a work around for this problem?

Any help would be greatly appreciated

Thanks

Rincewind
03 Aug 2006, 09:39 AM
The first step is to find which of your lines of code causes the error. Without knowing where in the code you get the error, we have to just guess. Try echoing the result to the screen are various points in the code to see just where the bug is.