1 Joing multiple datasets for grouping in the graph key
3 If you want to group datasets in the graph key, e.g., to compare simulation
4 results with measurement data ... or some approximate results with results from
5 a more detailed calculation, you can pass a list of datasets to the
6 `graph.data.join` class.
8 When doing so, you have to assign unique names to the corresponding datasets.
9 In the example, we have used `x_a` and `y_a` as well as `x_b` and
10 `y_b` as names. Subsequently, one has to tell the graph style which data
11 columns—identified by the given name—it has to plot. This can be done
12 by inserting `graph.style.pos` instances before the respective graph style. By
13 passing a dictionary to the `usenames` argument, one specifies the
14 mapping from the data columns to the corresponding graph axes `x`, `y`, `x2`,
17 ! When using the standard names `x`, `y`, etc. for the data columns, as is done
18 in most cases, PyX does insert the `graph.style.pos` instance mapping those
19 data columns to the axis with the same name, automatically.