Quantities with error bars

For some quantities in the data dictionary you can store the error bars in an IDS as well. This is indicated by a ⇹ symbol in the IDS reference.

When a quantity <data> supports errorbars, three additional quantities exist in the IDS:

  1. <data>_error_upper

  2. <data>_error_lower

  3. <data>_error_index

    Deprecated since version 3.39.0: The <data>_error_index elements are obsolescent.

The upper and lower errors are absolute and positive, and represent one standard deviation of the data. The effective values of the data (within one standard deviation) are in the interval [<data> - <data>_error_lower, <data> + <data>_error_upper].

Important

When the errors are symmetrical, <data>_error_lower may be empty and <data>_error_upper represents both the upper and lower error.

Example

global_quantities/ip in the core_profiles IDS has error bar nodes global_quantities/ip_error_upper and global_quantities/ip_error_lower.