Encyclopaedia Index
The TYPES of VARIABLE which can be set by PLANT, and therefore may take the place of VAR on the left-hand side of setting statements of the form:

VAR = expression

are as follows:-

FFV's
Full-Field Variables which have a stored value for each cell of the grid.

Examples are:

Insofar as the FFV's are not built-in-PIL variables (as PRPS. DEN1, VPOR and P1 are, while MARK and NU are not) their use must be preceded in the Q1 file by the appropriate STORE or SOLVE command.

RNV's
Real-Number single-value Variables which have but one distinct value;

The following RNV's are recognised by PLANT:

DT, DTFALS(PHI), DZ, RG(n), RESREF(PHI), VARMAX(PHI), VARMIN(PHI), XRAT, YRAT.

The PHOENICS Encyclopaedia explains their meanings.

RFV's
Real-Function full-field Variables which have values for each cell of the grid computed in EARTH by its real function subroutines;

The following RFV's are recognised by PLANT:

XC, YC, ZC, the cartesian coordinates of cell corners, in a body-fitted coordinate grid, at the current time and

XCO, YCO, ZCO, their corresponding value at the previous time instant.

CDV's
Command-Declared Variables which have but one distinct value and are automatically declared to be used by a PLANT command.