contrast_parser

helper function to calculate contrasts of one or more images using a combination of
image arithmetic and logical subsetting

internal

A 'ggplot2'-consistent approach to generating 2D displays of  volumetric brain imaging data.
Display data from multiple NIfTI images using standard 'ggplot2' conventions such scales, limits, and
themes to control the appearance of displays. The resulting plots are returned as 'patchwork' objects,
inheriting from 'ggplot', allowing for any standard modifications of display aesthetics supported by 'ggplot2'.

Michael Hallquist

ggbrain

Create Images of Volumetric Brain Data in NIfTI Format Using
'ggplot2' Syntax

contrast_parser function

<dl><dt>expr</dt>
<dd>a string or expression containing the image calculation to be performed</dd>
<dt>data</dt>
<dd>a data.frame containing all variables used in <code>expr</code>. This will be used
to perform contrast calculations</dd>
<dt>default_val</dt>
<dd>the value to be returned for any element of the contrast calculation that
does not pass through the arithmetic, either because of logical subsetting or because it
is exactly zero. In general, leave this as <code>NA_real_</code> unless you know what you're doing.</dd></dl>

Arguments

Author

helper function to calculate contrasts of one or more images using a combination of
image arithmetic and logical subsetting — contrast_parser

<dl>

<dt>expr</dt>
<dd>a string or expression containing the image calculation to be performed</dd>


<dt>data</dt>
<dd>a data.frame containing all variables used in <code>expr</code>. This will be used
to perform contrast calculations</dd>


<dt>default_val</dt>
<dd>the value to be returned for any element of the contrast calculation that
does not pass through the arithmetic, either because of logical subsetting or because it
is exactly zero. In general, leave this as <code>NA_real_</code> unless you know what you're doing.</dd>

</dl>

contrast_parser: helper function to calculate contrasts of one or more images using a combination of image arithmetic and logical subsetting

Description

Usage

Arguments

Author