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DVHmetrics (version 0.3.1)

showConstraint: Display constraints for cumulative dose-volume histograms

Description

Displays quality assurance constraints for cumulative dose-volume histograms: Either one diagram per patient - including multiple structures. Or one diagram per structure - including multiple patients.

Usage

showConstraint(x, constr, byPat=TRUE, rel=TRUE, guessX=TRUE, thresh=1)

## S3 method for class 'DVHs':
showConstraint(x, constr, byPat=TRUE, rel=TRUE, guessX=TRUE, thresh=1)

## S3 method for class 'DVHLst':
showConstraint(x, constr, byPat=TRUE, rel=TRUE, guessX=TRUE, thresh=1)

## S3 method for class 'DVHLstLst':
showConstraint(x, constr, byPat=TRUE, rel=TRUE, guessX=TRUE, thresh=1)

Arguments

x
A single DVH (object of class DVHs), multiple DVHs from one patient/structure (object of class DVHLst), or multiple DVHs from many patients/structures (object of class DVHLstLst). See
constr
One or more constraints - given as a character vector or as a data.frame. See checkConstraint for their definition.
byPat
Relevant if multiple DVHs are given. If x has class DVHLstLst: byPat=TRUE means that one diagram shows DVHs from one patient with multiple structures. byPat=FALSE means that one diagram shows DVHs for on
rel
logical. Show relative volume?
guessX
logical. Try to clip the x-axis for better visibility of main DVH range?
thresh
numeric value. Relative volume threshold used with guessX=TRUE. Clip x-axis (+10%) such that the "highest" DVH is cut off at this relative volume.

Value

  • Silently returns a ggplot diagram object, or - when multiple diagrams are constructed - a list of ggplot diagram objects.

Details

Constraints are shown as points in the cumulative DVH with an additional arrow indicating where the cumulative DVH curve should lie relative to the constraint. On each DVH curve, the point with the minimal Euclidean distance to the constraint is indicated. Note that, visually, this point only has the minimal apparent distance if the aspect ratio of the diagram is 1. If multiple diagrams are produced, they are shown in the same graphics device. If interactive inspection is required, make sure you use an R development environment that saves previous diagrams and allows navigating between them - e.g., http://www.rstudio.com/products/rstudio/download/{RStudio} or http://www.openanalytics.eu/downloads/architect{OpenAnalytics Architect}.

See Also

checkConstraint, saveDVH

Examples

Run this code
data(dataMZ)

# define constraints
constr <- data.frame(
    patID=c("P123", "P234"),
    structure=c("HEART", "*"),
    constraint=c("D1CC < 20Gy", "V10% > 8CC"),
    stringsAsFactors=FALSE)       # this is important
showConstraint(dataMZ, constr=constr, byPat=FALSE)

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