# Re: numberFormat question

```On 6/16/2014, 1:13 PM, dfepst...@comcast.net wrote:
```
```

I am trying to set the numberFormat so that calculation is precise enough for
the situation.  Since I don't know ahead of time how many decimal places will
be used, I wrote a function that I hoped would adjust things as necessary.
But when this function is called with parameters m = 1.09131 and n = .0000001
and k = 1, it returns 1.09131 rather than 1.0913101.
The last couple of lines were added for testing, and the debugger shows that
the numberFormat is being set correctly but that the truncated value is put
into hold.
Can anybody see what is going wrong?

Many thanks.

David Epstein

function preciseEnough m,n,k
-- return the value m + k*n
-- default numberFormat shows up to 6 decimal places
-- If m, n, or k  has more than that precision, this function sets the
numberFormat with a margin of safety
put length(m) - offset(".",m) into aPlaces
put length(n) - offset(".",n) into bPlaces
put length(k) - offset(".",k) into cPlaces
put the numberFormat into myString
if max(aPlaces,bPlaces,cPlaces) + 4 > length(myString) then
get myString & "####"
set the numberFormat to it
end if
put the numberFormat into nf
put m + k*n into hold
return hold
end preciseEnough
```
```
```
As Mark said, numberformat is only retained during the local handler so you need to reset it each time the handler runs.
```
```
When you use #, it means to include a numerical value in that postion only if there is an actual value there; if there is no value then that position is ignored. If you use 0 in the numberformat instead, empty positions are padded with zeros. So, to get the precision you want, you don't need to calculate the number of places/positions, just use the # as you are now. Include enough #s to cover your longest anticipated number, up to LC limits (I think that's 16 places.)
```
```
Since numberformat only affects the display, you need to force the calculation from a numerical value to a text value. You can do that by simply putting the result of the calculation into a field. If you want it in a variable, you can use value() to do that instead.
```
So your whole handler can be like this:

function preciseEnough m,n,k
put m + k*n into hold
set the numberformat to "0.##############" -- add more if you want
put value(hold) into hold
return hold
end preciseEnough

--
Jacqueline Landman Gay         |     jac...@hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com

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