NAME

kplot_attach_datas — assign multi-plot data to plotting context

LIBRARY

library “libkplot”

SYNOPSIS

#include <cairo.h>
#include <kplot.h> int
kplot_attach_datas(const struct kplot *p, size_t sz, struct kdata **d, const enum kplottype *t, const struct kdatacfg *const *cfg, enum kplotstype st);

DESCRIPTION

The kplot_attach_datas function assigns a “multi-data” source set d to a plotting context p, reference-counting the data sources in the process. See kplot_attach_data(3) for a more general description of attaching data. Multi-data source sets consist of a baseline and one or more pair lines, for example, a curve and its error bars. The most common usage is for graphing mean (the baseline) and standard deviation above and below (pair lines) via kdata_mean_alloc(3) and kdata_stddev_alloc(3). The order in which you arrange the array parameters d, t, and cfg: the first is for the baseline, subsequent are for pair lines as defined by st. The cfg argument can be NULL (as can individual array entries); all other parameters and indexes must not be NULL. The plot types are as follows:

KPLOTS_YERRORLINE

Draw a baseline (or points) using the first element in d. The next element is used to draw error lines (or points) above (adding to the y-position) and below (subtracting) the baseline. Subsequent lines are ignored. Data sources are matched by bucket index, not x-axis value, which is ignored for all pair data sources.

KPLOTS_YERRORBAR

Draw a baseline (or points) using the first element in d. The next element is used to draw error lines (or point) above (adding to the y-position) and below (subtracting) the baseline. A bar is then drawn between these points using the line configuration of this element. Subsequent lines are ignored. Data sources are matched by bucket index, not x-axis value, which is ignored for all pair data sources.

RETURN VALUES

kplot_attach_datas returns 0 if allocation of internal structures fails due to memory exhaustion, or not enough data sources have been provided. In this case, all allocations and references will be dropped.

SEE ALSO

kplot(3), kplot_attach_data(3), kplot_attach_smooth(3)