The 3D biplot opens an interactive 3D device that can be rotated and zoomed using the mouse. A 3D device facilitates the exploration of grid data as significant proportions of the sum-of-squares are often represented beyond the first two dimensions. Also, in a lot of cases it may be of interest to explore the grid space from a certain angle, e.g. to gain an optimal view onto the set of elements under investigation (e.g. Raeithel, 1998).

## Usage

```
biplot3d(
x,
dim = 1:3,
labels.e = TRUE,
labels.c = TRUE,
lines.c = TRUE,
lef = 1.3,
center = 1,
normalize = 0,
g = 0,
h = 1,
col.active = NA,
col.passive = NA,
c.sphere.col = grey(0.4),
c.cex = 0.6,
c.text.col = grey(0.4),
e.sphere.col = grey(0),
e.cex = 0.6,
e.text.col = grey(0),
alpha.sphere = 0.05,
col.sphere = "black",
unity = FALSE,
unity3d = FALSE,
scale.e = 0.9,
zoom = 1,
...
)
```

## Arguments

- x
`repgrid`

object.- dim
Dimensions to display.

- labels.e
Logical. whether element labels are displayed.

- labels.c
Logical. whether construct labels are displayed.

- lines.c
Numeric. The way lines are drawn through the construct vectors.

`0 =`

no lines,`1 =`

lines from constructs to outer frame,`2 =`

lines from the center to outer frame.- lef
Construct lines extension factor

- center
Numeric. The type of centering to be performed. 0= no centering, 1= row mean centering (construct), 2= column mean centering (elements), 3= double-centering (construct and element means), 4= midpoint centering of rows (constructs). Default is

`1`

(row centering).- normalize
A numeric value indicating along what direction (rows, columns) to normalize by standard deviations.

`0 = none, 1= rows, 2 = columns`

(default is`0`

).- g
Power of the singular value matrix assigned to the left singular vectors, i.e. the constructs.

- h
Power of the singular value matrix assigned to the right singular vectors, i.e. the elements.

- col.active
Columns (elements) that are no supplementary points, i.e. they are used in the SVD to find principal components. default is to use all elements.

- col.passive
Columns (elements) that are supplementary points, i.e. they are NOT used in the SVD but projected into the component space afterwards. They do not determine the solution. Default is

`NA`

, i.e. no elements are set supplementary.- c.sphere.col
Color of construct spheres.

- c.cex
Size of construct text.

- c.text.col
Color for construct text.

- e.sphere.col
Color of elements.

- e.cex
Size of element labels.

- e.text.col
Color of element labels.

- alpha.sphere
Numeric. alpha blending of the surrounding sphere (default

`".05"`

).- col.sphere
Color of surrounding sphere (default

`"black"`

).- unity
Scale elements and constructs coordinates to unit scale (maximum of 1) so they are printed more neatly (default

`TRUE`

).- unity3d
To come.

- scale.e
Scaling factor for element vectors. Will cause element points to move a bit more to the center (but only if

`unity`

or`unity3d`

is`TRUE`

). This argument is for visual appeal only.- zoom
Not yet used. Scaling factor for all vectors. Can be used to zoom the plot in and out (default

`1`

).- ...
Parameters to be passed on.

## References

Raeithel, A. (1998). Kooperative Modellproduktion von
Professionellen und Klienten - erlauetert am Beispiel des
Repertory Grid. *Selbstorganisation, Kooperation, Zeichenprozess:
Arbeiten zu einer kulturwissenschaftlichen, anwendungsbezogenen
Psychologie* (pp. 209-254). Opladen: Westdeutscher Verlag.

## See also

Unsophisticated biplot: `biplotSimple()`

;

2D biplots:
`biplot2d()`

,
`biplotEsa2d()`

,
`biplotSlater2d()`

;

Pseudo 3D biplots:
`biplotPseudo3d()`

,
`biplotEsaPseudo3d()`

,
`biplotSlaterPseudo3d()`

;

Interactive 3D biplots:
`biplot3d()`

,
`biplotEsa3d()`

,
`biplotSlater3d()`

;

Function to set view in 3D:
`home()`

.

## Examples

```
if (FALSE) {
biplot3d(boeker)
biplot3d(boeker, unity3d = T)
biplot3d(boeker,
e.sphere.col = "red",
c.text.col = "blue"
)
biplot3d(boeker, e.cex = 1)
biplot3d(boeker, col.sphere = "red")
biplot3d(boeker, g = 1, h = 1) # INGRID biplot
biplot3d(boeker,
g = 1, h = 1, # ESA biplot
center = 4
)
}
```