The datatypes[] array contains information about the available data types. See Section 3.3, “PHPlot Data Types” for more information about data types. It is used by SetDataType to validated the supplied data type, and by DecodeDataType to set the flags that describe the datatype.

The goal is to keep the names and details about the data types in this array only, and minimize other uses of the actual data type names. However, each plot type drawing function (for example DrawLines) also 'knows' about the data types it supports, and specifies the data type names when calling CheckDataType.

This array was added in PHPlot-6.1.0. It is a protected static member variable in the PHPlot class, so it must be accessed as self::$datatypes from inside the class (or a derived class), and not through an instance of the class. Is not accessible from outside the class or derived classes.

The array keys are the data types (for example: 'text-data'). The values are arrays which contain information about the data type. The second-level array keys correspond to the 'datatype' flag variables, without the 'datatype_' prefix. A key will be present, with the value TRUE, if the flag should be set for that data type. The key will be absent if the flag should not be set. For example: for data type text-data, the array contains one value: 'implied' => TRUE. This means that for data type text-data, the datatype_implied flag should be TRUE (indicating that this data type has implied independent variable values), and all other flags should be FALSE. In addition to implied, the other possible keys are pie_single, error_bars, swapped_xy, and yz.

The fonts[] array contains information about the fonts to use for text on the plot. The array keys are the element names (such as title or legend) as used in SetFont, SetFontGD, or SetFontTTF. The array values are arrays which contain information about the font to use for that element. The keys and values of the second-level arrays are:

For TrueType fonts, the height and width can vary by character. The fonts array stores a height and width value for the font, but these are only used for sizing non-text plot elements (such as the legend color boxes). When PHPlot needs to know the drawn size of a string that will use TTF, it calculates the exact size of that specific string when drawn with the designated font.

GD fonts have fixed character width and height, so the values stored in the fonts array can be used to calculate text string sizes.

The spacing key stores the TrueType font's built-in inter-line spacing. Although TrueType fonts have this information internally, PHP cannot access it, so PHPlot calculates it by taking the height of the string "E\nE" and subtracting twice the height of the letter E.

The line_spacing key stores the user-specified line spacing adjustment for a text element, if any, from SetFont or one of the two related functions. It will be NULL if the spacing was not set for this element, meaning use the default line spacing. See SetLineSpacing for more information on how this is used.

Here is an example of part of a fonts array, for the title element:

$plot->fonts['title'] = array(
    'ttf' => FALSE,          // This element uses a GD font
    'font' => 2,             // Use GD font 2
    'height' => 13,          // Provided by GD
    'width' => 6,            // Provided by GD
    'line_spacing' => NULL,  // Use default line spacing
)

The label_format[] array contains information about how text labels should be formatted. This array has 5 entries, with keys 'x', 'y', 'xd', 'yd', and 'p'. The 'x' and 'y' entries are for tick labels, and the 'xd' and 'yd' entries are for data labels. (Note that PHPlot defaults data label formatting to match tick label formatting, but this is handled in FormatLabel.) The 'p' entry is for pie chart labels, and will only exist for pie charts. (The 'p' entry was added in PHPlot-5.6.0.)

The value of each entry in label_format is an array containing formatting information. The arrays are empty by default, meaning there is no special formatting. If formatting has been enabled, for example with SetXLabelType, the arrays can contain the following keys and values:

Use of multiple strings for printf_format was added in PHPlot-6.2.0.

The legend_pos[] array contains information about positioning of the legend. This is set by SetLegendPosition, and by the functions which use it (SetLegendPixels and SetLegendWorld). This was added in PHPlot-5.4.0, replacing scalar variables legend_x_pos, legend_y_pos, and legend_xy_world.

The array keys correspond to the arguments to SetLegendPosition and are shown in the following table.

The plots[] array contains information about known plot types. It is used by FindDataLimits, DrawGraph, and other class functions to prepare for and draw the main portion of the plot. The goal is to contain the information about each available plot type in a single place - this array. The actual names of the plot types (for example 'bars' or 'linepoints') appear only in this array. To simplify somewhat, adding a new plot type to PHPlot involves adding a new element to the plots[] array, and adding a new function to PHPlot which draws the 'insides' of the plot.

This array was added in PHPlot-5.3.0. It is a protected static member variable in the PHPlot class, so it must be accessed as self::$plots from inside the class (or a derived class), and not through an instance of the class. Is not accessible from outside the class or derived classes.

The array keys are the plot types (for example: 'bars', 'linepoints'). These must not include upper case letters. The values are arrays which contain information about the plot type. The keys and values of the second-level arrays are:

Only the draw_method entry is required. The named method is used to draw everything inside the plot area. (That is, everything except the plot titles, axis lines, tick marks and tick labels, grid lines, and legend.)

The draw_arg entry can be used to pass constant arguments to the draw_method method. If present, this must be an array, and each element of the array is passed to the drawing method as a separate argument. If this is not specified, the drawing method is called with no arguments. This is generally used to overload drawing methods, so they handle multiple similar plot types.

The suppress_axes flag indicates that X and Y axis lines should not be drawn (used with pie charts, for example). If omitted, FALSE is used, meaning the axis lines are drawn. (Before PHPlot-6.0.0 this was called draw_axes, with default TRUE, and FALSE for pie charts.)

The two special data processing flags abs_vals and sum_vals are used by FindDataLimits to indicate how to compute the minimum and maximum data values. Plot types that ignore sign and take absolute values of the data set abs_vals to TRUE. Plot types that sum up the data values in each row set sum_vals to TRUE. The default if omitted for both flags is FALSE, meaning the plot type uses the values as specified in the data array. If both abs_vals and sum_vals are TRUE, this means the plot type sums up the absolute values from the data array. (The stackedarea plot type does this.)

The optional legend_alt_marker entry indicates the use of an alternate maker shape in legends. Use SetLegendUseShapes to select either the primary mode or the alternate mode for legend shapes. The primary mode is a solid filled color box. The alternate mode varies with the plot type, according the the legend_alt_marker entry. Use 'box' for rectangular color boxes. This is the default if the legend_alt_marker key is omitted from the array. Effectively, this means there is no alternate marker mode for these plot types, because color boxes are the primary mode. Use 'shape' for point shape markers, which applies to points plots and similar types which use point shapes. Use 'line' for short line segments, which applies to line plots and similar types.

The optional adjust_type entry controls adjustments made to the end of an automatically calculated plot range. See TuneXAutoRange and TuneYAutoRange for more information. This is used to indicate when a plot type needs additional space, perhaps for labels, between the data extrema and the edge of the plot area. If omitted, the default value 0 is used. A value of 0 means apply the adjustment for the dependent variable only. A value of 1 means apply the adjustment for both X and Y, and a value of 2 means do not apply the adjustment to either X or Y.

The rangectl[] array contains parameters which are used to control the automatic calculation of the plot area range.

The array contains 2 arrays, indexed as 'x' and 'y' for X and Y axis parameters respectively. The keys and values of the second-level arrays are:

Values in this array are set with TuneXAutoRange and TuneYAutoRange. For more information see Section 4.6.4, “Automatic Range Parameters”. The values are used by CalcPlotRange.

The tickctl[] array contains parameters which are used to control the automatic calculation of tick intervals.

The array contains 2 arrays, indexed as 'x' and 'y' for X and Y axis parameters respectively. The keys and values of the second-level arrays are:

Values in this array are set with TuneXAutoTicks and TuneYAutoTicks. For more information see Section 4.6.8, “Automatic Tick Increment Parameters”. The values are used by CalcStep.