lav_plotinfo_positions: Position the nodes in the diagram

Description

Computes the positions for the nodes and anchors and control points for the edges in the diagram.

Usage

lav_plotinfo_positions(plotinfo,
                       placenodes = NULL,
                       edgelabelsbelow = NULL,
                       group_covar_indicators = FALSE,
                       debug = FALSE)

Value

A plotinfo structure with modified nodes and edges

data.frames, and an integer mlrij giving the position at which a line should be drawn for multilevel models.

The data.frames have new columns defined as follows:

nodes

rij

index of the row where the node will be placed, initialized NA.

kolom

index of the column where the node will be placed, initialized NA.
edges

vananker

character, anchor point for starting node, initialized NA.

naaranker

character, anchor point for destination node, initialized NA.

controlpt.kol

real, column position of control point if the edge has to be drawn as a quadratic Bezier curve.

controlpt.row

real, row position of control point if the edge has to be drawn as a quadratic Bezier curve.

labelbelow

logical, TRUE if label has to be positioned under the line, initialized FALSE.

Arguments

plotinfo: The plotinfo structure as returned from lav_model_plotinfo.
placenodes: optional list with members nodename = c(row, column), row and column don't have to be integers.
edgelabelsbelow: optional list with members c(nodename1, nodename2).
group_covar_indicators: logical, should items with indicators which have an explicit covariance link be placed in the same group, i.e. forced to be on the same side of the diagram?
debug: logical, print debug information?

Details

This function tries to arrange the nodes and the anchor points for the edges in a way that keeps the diagram reasonably compact, while placing the dependent variable of a regression to the right of the variables it depends on. If the result is not what you want, you can inspect the plot with the lav_plotinfo_rgraph or lav_plot functions and then place some nodes at a different location (placenodes) and/or move some edge labels to the other side of the edge (labelsbelow).

For multilevel models -- maximum two levels -- the nodes in block 2 are grouped at the top of the diagram and those in block 1 at the bottom. The item mlrij gives the position of the separation between the blocks.

Examples

Run this code

model <- 'alfa  =~ 1 * x1 + x2 + x3         # latent variable
          beta <~ x4 + x5 + x6              # composite
          gamma =~ 1 * x7 + x8 + x9         # latent variable
          Xi =~ 1 * x10 + x11 + x12 + x13   # latent variable
          # regressions
          Xi ~ v * alfa + t * beta + cc * 1
          alfa ~ tt * beta + ss * gamma + yy * Theta1
          # variances and covariances
          x2 ~~ cc25 * x5
          x3 ~~ cc36 * x6
          x3 ~~ cc34 * x4
          gamma ~~ 0.55 * gamma
          '
test <- lav_model_plotinfo(model)
(test_positioned <- lav_plotinfo_positions(test))