Hach Lange DR 3900 User Manual page 88

Expanded programs
Screen
88
Table 11 Description of the keys for the editing of formulae
Abs/Variables
New Number
Key Description
Press the Abs/Variables key to select, from the
displayed list, the required element of the defined
measuring sequence and therefore the corresponding
reading wavelength, so that this can be taken into
account in the formula.
Press New Number to enter a new factor or constant.
÷
Press + – × to enter a mathematical operation.
Select the operation and press OK to confirm.
The available choice of mathematical operations
depends on the defined formula.
This means that functions such as "( )" or "ln"/"log" etc.
are only active if a term in parentheses or the calculation
of a logarithm is mathematically permissible in the
defined formula (this also applies to the basic
mathematical operations).
The following mathematical operations are available:
÷
+ – ×
• + (Addition)
• - (Subtraction)
÷ (Division)
•
• × (Multiplication)
• ^ (Exponent)
• Ln (Natural logarithm)
• Log (Common logarithm)