Metrohm viva 1.0 Manual - Manual (Page 28)

2.3 Formula editor
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16 ￭￭￭￭￭￭￭￭
viva 1.0
the basis of the IEEE 754 standard means that the decimal numerals
resulting from this have 15 reliable significant decimal places.
You can influence the number of significant digits by selecting the unit
and the number of decimal places. As the result unit to be set sometimes
contains the prefix "milli" as well as the actual physical unit, the number of
significant places changes accordingly by three places during such a con-
version.
Example
The displayed result of 1,234.56789158763 mg/L has 15 reliable digits.
It should be rounded off to three decimal places according to the above
rounding-off process:
1,234.568 mg/L (7 significant places, 3 of them decimal places)
The unit "g/L" means that the same result 1.23456789158763 g/L is
also rounded off to three decimal places:
1.235 g/L (4 significant places, 3 of them decimal places)
The number of significant digits has now been reduced by three to four
digits by omitting the prefix "milli".
NOTE
The above losses with respect to accuracy caused by rounding off in the
range of the maximum reliable places are only theoretically relevant.
Most of the time they are lower by several orders of magnitude than,
for example, the uncertainties resulting from sample size.
2.3.3 Variables
2.3.3.1 Variables - Overview
Dialog window: Formula editor
Variables are automatically generated by the program during or at the end
of the determination. You can use the formula editor to access these and
either use the values for further calculations or output them in reports as a
result.
Variable types
The following types of variables are differentiated:
Name Syntax Description
Sample data var-
iables 'SD.Variable
name.Variable identifi-
cation' Sample data variables contain all of the sample data of the determi-
nation.