| addInterval | Draw intervals or arrows on plots. |
| add_bars | Adding bars to an existing plot. |
| add_n_points | Add groups of points to a plot |
| alpha | Adjusting the transparency of colors. |
| alphaPalette | Manipulate the transparency in a palette. |
| check_normaldist | Compare distribution of data with normal distribution. |
| color_contour | Creates a contour plot with colored background. |
| convertFile | Replacing separators (for example, decimal and thousand separators). |
| dotplot_error | Utility function |
| drawDevArrows | Draw arrows between different plots. |
| emptyPlot | Utility function |
| errorBars | Add error bars to a plot. |
| fill_area | Utility function |
| findAbsMin | Return the value (or the element with the value) closest to zero. |
| find_n_neighbors | Return n neighbors around given indices. |
| firstLetterCap | Capitalize first letter of a string. |
| getArrowPos | Converts coordinates in current plot region to device positions (in inch). |
| getCoords | Convert proportions into coordinates of the plot or figure region. |
| getDec | Return the number of decimal places. |
| getFigCoords | Get the figure region as coordinates of the current plot region, or as corrdinates of the figure region. |
| getProps | Transform coordinates into proportions of the figure or plot region. |
| getRange | Function for rounding and/or segmenting a range. |
| getRatioCoords | Move a vector n elements forward or backward. |
| get_palette | Retrieve the color scheme for contour plots. |
| gradientLegend | Add a gradient legend to a plot. |
| group_sort | Sort split by grouping predictor. |
| img | Image object. |
| inch2coords | Convert device position (inch) to coordinates in current plot region. |
| isColor | Check whether color specifications exists. |
| legend_margin | Add legend with respect to figure instead of plot region. Allows to move legend to margin of plot. |
| list2str | Combine list values as string. |
| marginDensityPlot | Plot density of distribution in margins of the plot. |
| move_n_point | Move a vector n elements forward or backward. |
| orderBoxplot | Order boxplot stats following a given ordering. |
| plotfunctions | Package plotfunctions: Various Functions to Facilitate Visualization of Data and Analysis |
| plotsurface | Creates a colored surface plot from data frame input. |
| plot_error | Utility function |
| plot_image | Add images to plots. |
| plot_signifArea | Creates a colored surface plot from data frame input. |
| se | Calculate standard error of the mean. |
| sortBoxplot | Produce box-and-whisker plot(s) ordered by function such as mean or median. |
| sortGroups | Sort groups based on a function such as mean value or deviation. |