Plotting and nonlinear fitting software
1. Select column and write formula in formula string.
Table → Set Column Formula menu item to open column formula dialog window. See Expression Syntax for details.
i contains the current row index. Rows are enumerated from 1.
Rows are always evaluated one after another from the first to the last in the specified range. Accordingly the row number
i is incremented after each step.
1in the first row of column
Aand after that set formula
cell(A, i-1) * iand rows interval from
100. Note that formula is to be set for rows beginning from the second, and not from the first. You will get the factorial of row number (
There are two functions to obtain current table cell values in formula:
col(A)– returns the value of cell in column
Ain the current (i-th) row. Equivalent to
cell(A, 3)– returns the value in column
You can use either upper-case letters (
col(B)) or numbers (
1, 2, 3,.., e.g.
col(1)) in columns numeration in arguments of
col(A) + 15 + cell(B, i+1)
MagicPlot can automatically recalculate formula when data in used columns are changed. Set
Auto Recalculate checkbox to enable this feature.
col(A)*2for column B and set
Auto Recalculatecheckbox. Column B will be recalculated if you change values in column A or column A is updated by other formula or processing algorithm (e.g. integral, derivative of other column).
You can edit column formula and change auto recalculation mode from column context menu or menu
Table. Select exactly one column and open context menu to view this menu items.
Some mathematical functions can be defined only on a certain interval. For example, square root (
sqrt(x)) is not defined for negative numbers (all calculations in MagicPlot are made in real numbers, not complex). Hence if the argument of
sqrt is negative, a Not-a-Number (NaN) is returned. If a NaN value occurs in some part of formula, the result of calculation will also be a NaN, and corresponding table cells will be empty.
The calculations are not terminated if NaN value occurs in some row(s).
In some cases you may want to check if a
NaN values occurs in calculations. MagicPlot shows the warning “Argument is out of range at row #”. This row number is the first row in which
NaN value was returned. MagicPlot also highlights the function or operator which first produces NaN value.