How to multiply very small numbers withot round it to zero ?

[weaam]

Hi  everyone

When I multiply  tow values one of them have very small numbers (import from Excel) labview round  them to zero . How would i stop it from happenning?

Thank you.

[altenbach]

We cannot tell from the picture, but is it also zero if you use a scientific display format?

(Please attach the VI and also include a typical data file)

[RavensFan]

It's impossible to debug a picture.  Attach your VI and also the text file that contains your data.  That way we can see how small these numbers actually are.  LabVIEW doesn't just round small numbers to zero, so I think you've got something else going wrong in your program, either the way it is reading the text file, or the way you are displaying your results.

[GerdW]

Hi weaam,

please provide an example for your problem!

LabVIEW will not round to zero unless the numbers are VERY small in the order of 1E-323 for DBL values…

What formatting did you set for the array indicator you marked in your image?

[wiebe@CARYA]

If the values where really zero, all values after it would also be zero ("-10000000*V*exp(") or one ("p(D)" and "TCP"). 0X-10000000=0, exponential(zero)=1, 1*1=1...

It just shows as zero's, since the default formatting is not useful in your situation (like the others mentioned).

[weaam]

altenbach , RavensFan and GerdW
thank you very much
the result is zero  when I use a scientific display format

[GerdW]

Hi weaam,

please attach images directly in this forum to be visible for everyone…

[wiebe@CARYA]

Make the values default, and post the saved VI... Or post the Vi and a data file. All kinds of things can be wrong, but we can't tell from an image.

[weaam]

Vi and data file

[GerdW · Accepted solution]

Hi weaam,

I don't see any errors in those calculations!

Either the volume is zero (most of the time) or you try to calculate e^x for very small x values (like -26000).

Example: for row 1300 you get a "Dose" value of 6500. Then you calc "-0.307*D*(1+D/300)", which results in -45231.33. Now take e^-45231: this will result in (basically) zero!

Which result do you expect for your input values?

Side note: Setting the indicators to 50 significant digits is nonsense for DBL values: they only support ~17 decimal digits!