Wave:Calculator

Wave | Download | Development

The Calculator analysis function performs mathematical operations on time series.

The mathematical operations to be performed are entered as a formula or mathematical expression. The formula is individually applied to each of the timestamps contained in the series that were selected for the analysis. The result is a new time series.

The following mathematical operators are supported:

• (): Parenthesis
• +: Addition operator e.g. 3 + 2
• -: Subtraction operator e.g. 3 - 2
• *: Multiplication operator e.g. 3 * 2
• /: Division operator e.g. 3 / 2
• %: Modulus operator e.g. 3 % 2 (divides the two numbers, but returns the remainder)
• ^: Exponent operator e.g. 3 ^ 2
• ABS: Returns the absolute of a number e.g. ABS(-3)
• SIN: Returns the sine of a number e.g. SIN(3.14)
• COS: Returns the cosine of a number e.g. COS(3.14)
• TAN: Returns the tangent of a number e.g. TAN(3.14)
• LOG: Returns the base 10 logarithm of a number e.g. LOG(3)
• LOGN: Returns the natural logarithm of a number e.g. LOGN(4)

Time series selected for this analysis can be added to the formula as variables either by entering the letter representing the time series manually or by double-clicking the time series in the list box.

The calculation only results in a value for those timestamps that are common to all of the time series selected for analysis. If a timestamp is missing in one or more time series or the value of one or more time series is NaN for a timestamp, the resulting time series will have a NaN value for this particular timestamp.

Examples:

• 100 (without any variables):

results in a time series with the value of 100 for each timestamp

• A / 100 (where A is a time series):

results in a time series where all values of A are divided by 100

• A + B (where A and B are time series):

results in a time series where the values of A and B are added to together for each common timestamp

• (2 * A) + LOG(B) - ABS(C) (where A, B and C are time series):

complex calculation with multiple time series

Note: The Math Parser .NET library is used for parsing and evaluating the mathematical expression.