LV 2017 ignores format string for double

[quailstorm]

Hello!

I have a little "homework" I need to hand in tomorrow, and one of the questions is:

Give a format string which you can read in a data with 6 decimal points. The decimal delimiter is point. I live in Hungary, therefore the system default is ",".

My current format string according to the official help is: %.;%.6f

But the .6f part seems to be ignored by LV. It reads every decimal. The digit before the dot (width) does have effect on the output.

What can be wrong?

See attachments for example. (there is another test.txt with commas instead of dots, but that does not matter)

Thanks in advance for the reply.

[altenbach · Accepted solution]

It is documented that scanning a string uses a simplfied format where only the conversion code is used.

%[Width]Conversion Code

If you want to see fewer digits, adjust the format of the indicators.

Many exact decimal values cannot be represented exactly in binary (e.g. 0.1), so the value of any numeric will be the closest binary value, which might have other nonzero decimal digits on the far right once you display many.

[quailstorm]

Thanks, I totally missed that part. I see now, I can only use this C style format string to convert from numeric or numeric array to string. But since LV has its own logic there is no need to round or cut inputs I guess.

About floating point numbers, I know that is the reason of the weird endings, but the last number in my txt had more than 6 decimals. That was the test number (0.11111122222225).