TwissGrid

This application performs one- or two-dimensional grid scans of lattice parameters and visualizes their effect on selected optics functions.

Installation

The application can be installed from the Python Package Index (PyPI):

pip install twissgrid

Usage

The application can be used from the command line in the following way:

python -m twissgrid /path/to/script.madx a_param

It expects at least two arguments:

1. The file path to a MADX script.
2. The name of a lattice parameter. It needs to be given as label->attr where the ->attr part is optional (it will be inferred from the element type). The corresponding element must be accessible in MADX via the provided label (internally the parameter will be updated as label->attr = value; so that must be an effective statement).

This example will create a 2D-plot of the beta functions in dependence on that parameter:

3D Plots

A second parameter can be provided, following the first one, in order to perform a two-dimensional parameter scan and create a corresponding 3D-plot:

python -m twissgrid /path/to/script.madx a_param b_param

Customization

The application supports various other arguments for customizing the parameter scan or the resulting plots. The full set of available parameters can be found via --help:

$ python -m twissgrid --help
usage: python -m twissgrid [-h] [--p1lb P1LB] [--p1ub P1UB]
                           [--p1delta P1DELTA] [--p1margin P1MARGIN]
                           [--p1n P1N] [--p2lb P2LB] [--p2ub P2UB]
                           [--p2delta P2DELTA] [--p2margin P2MARGIN]
                           [--p2n P2N] [--funcs FUNCS [FUNCS ...]]
                           [--target TARGET] [--beta0 BETA0]
                           [--threshold [THRESHOLD [THRESHOLD ...]]]
                           [--figsize FIGSIZE FIGSIZE]
                           script p1 [p2]

positional arguments:
  script                File path to MADX script
  p1                    Lattice parameter 1 (format: label[->attribute])
  p2                    Lattice parameter 2 (format: label[->attribute])
                        (default: None)

optional arguments:
  -h, --help            show this help message and exit
  --funcs FUNCS [FUNCS ...]
                        Optics functions to plot (default: ('betx', 'bety'))
  --target TARGET       Label of the target element where optics functions are
                        observed (default: #e)
  --beta0 BETA0         Label of BETA0 command (this must be part of the MADX
                        script) (default: None)
  --threshold [THRESHOLD [THRESHOLD ...]]
                        Plot threshold line on each optics plot (default:
                        None)
  --figsize FIGSIZE FIGSIZE
                        Figure size in inches (default: (14, 10))

Parameter 1:
  --p1lb P1LB           Lower boundary for parameter scan (default: None)
  --p1ub P1UB           Upper boundary for parameter scan (default: None)
  --p1delta P1DELTA     Compute missing boundaries as a distance to the
                        current value (i.e. "lb = value - delta" and "ub =
                        value + delta"); --delta takes precedence over
                        --margin (default: None)
  --p1margin P1MARGIN   Compute missing boundaries as a fraction of the
                        current value (i.e. "lb = (1 - margin)*value" and "ub
                        = (1 + margin)*value") (default: 0.01)
  --p1n P1N             Number of grid points for parameter scan (default:
                        100)

Parameter 2:
  --p2lb P2LB           Lower boundary for parameter scan (default: None)
  --p2ub P2UB           Upper boundary for parameter scan (default: None)
  --p2delta P2DELTA     Compute missing boundaries as a distance to the
                        current value (i.e. "lb = value - delta" and "ub =
                        value + delta"); --delta takes precedence over
                        --margin (default: None)
  --p2margin P2MARGIN   Compute missing boundaries as a fraction of the
                        current value (i.e. "lb = (1 - margin)*value" and "ub
                        = (1 + margin)*value") (default: 0.01)
  --p2n P2N             Number of grid points for parameter scan (default:
                        100)