### Options

`FIRSTPLOT` = string token |
Defines the starting location for numbering the plots (`lowleft` , `lowright` , `upleft` , `upright` ); default `uple` |

`PLOTORDER` = string token |
Defines the order in which the numbers are allocated (`colserpentine` , `colbycol` , `rowserpentine` , `rowbyrow` ); default `rowb` |

### Parameters

`NROWS` = scalars |
Number of rows in the design |

`NCOLUMNS` = scalars |
Number of columns in the design |

`PLOTNUMBER` = factors |
Saves the plot numbers |

### Description

`FPLOTNUMBER`

generates unique numbers that can be used to identify the plots in a row-by-column design. These are often used to define the order in which various husbandry operations will be carried out. Several ways are therefore provided to specify the order.

The `FIRSTPLOT`

option specifies where the numbering should start, as follows:

`lowleft` |
left-hand plot at the bottom of the design i.e. in the final row and first column; |

`lowright` |
right-hand plot at the bottom of the design i.e. in the final row and final column; |

`upleft` |
eft-hand plot at the top of the design i.e. in the first row and first column (default); |

`lupright` |
right-hand plot at the top of the design i.e. in the first row and final column. |

The `PLOTORDER`

option defines the order in which the plots are then allocated:

`colserpentine` |
column-by-column in a serpentine way e.g. top-to-bottom, then bottom to top, and so on; |

`colbycol` |
column-by-column taking the same direction for every column; |

`rowserpentine` |
in a serpentine way e.g. left-to-right, then right-to-left, and so on; |

`rowbyrow` |
row-by-row taking the same direction for every row (default). |

The numbers of rows and columns defined by the `NROWS`

and `NCOLUMNS`

parameters, respectively. The `PLOTNUMBER`

parameter saves the numbers, in a factor.

Options: `FIRSTPLOT`

, `PLOTORDER`

.

Parameters: `NROWS`

, `NCOLUMNS`

, `PLOTORDER`

.

### Method

The procedure first forms row and column factors using the GENERATE directive, with the `FIRSTPLOT`

option indicating whether they are generated with their levels in ascending or descending order. The plot numbers are then calculated from those factors. With the serpentine orders, a different calculation is required for the even- and the odd-numbered rows or columns.

### See also

Commands for: Design of experiments.

### Example

CAPTION 'FPLOTNUMBER example'; STYLE=major SCALAR nr,nc; VALUE=7,5 FACTOR [NVALUES=nr*nc; LEVELS=nr] Row FACTOR [NVALUES=nr*nc; LEVELS=nc] Col GENERATE Row,Col "Display plot number from all 4 corners by 4 orderings" FOR FP = 'upleft','upright','lowleft','lowright' FOR PO = 'rowbyrow','rowserpentine','colbycol','colserpentine' FPLOTNUMBER [FIRSTPLOT=#FP; PLOTORDER=#PO] NROWS=nr; NCOLUMNS=nc; \ PLOTNUMBER=Plot TABULATE [CLASS=Row,Col] !(#Plot); MEANS=rc TXCONST [TEXT=head] 'FIRSTPLOT=',FP,' PLOTORDER=',PO CAPTION head; STYLE=minor PRINT [SQUASH=yes; IPRINT=*; RLWIDTH=6] rc; DECIMALS=0; FIELD=4 ENDFOR ENDFOR