flixopt.config ¶

Classes¶

MultilineFormatter ¶

MultilineFormatter(*args, **kwargs)

Bases: Formatter

Custom formatter that handles multi-line messages with box-style borders.

Uses Unicode box-drawing characters for prettier output, with a fallback to simple formatting if any encoding issues occur.

Functions¶

format ¶

format(record)

Format multi-line messages with box-style borders for better readability.

ColoredMultilineFormatter ¶

Bases: ColoredFormatter

Colored formatter with multi-line message support.

Uses Unicode box-drawing characters for prettier output, with a fallback to simple formatting if any encoding issues occur.

Functions¶

format ¶

format(record)

Format multi-line messages with colors and box-style borders.

CONFIG ¶

Configuration for flixopt library.

Attributes:

Name	Type	Description
`Logging`		Logging configuration (see CONFIG.Logging for details).
`Modeling`		Optimization modeling parameters.
`Solving`		Solver configuration and default parameters.
`Plotting`		Plotting configuration.
`config_name`	`str`	Configuration name.

Examples:

# Quick logging setup
CONFIG.Logging.enable_console('INFO')

# Or use presets (affects logging, plotting, solver output)
CONFIG.exploring()  # Interactive exploration
CONFIG.debug()  # Troubleshooting
CONFIG.production()  # Production deployment
CONFIG.silent()  # No output

# Adjust other settings
CONFIG.Solving.mip_gap = 0.001
CONFIG.Plotting.default_dpi = 600

Classes¶

Logging ¶

Logging configuration helpers.

flixopt is silent by default (WARNING level, no handlers).

Quick Start - Use Presets

These presets configure logging along with plotting and solver output:

Preset	Console Logs	File Logs	Plots	Solver Output	Use Case
`CONFIG.exploring()`	INFO (colored)	No	Browser	Yes	Interactive exploration
`CONFIG.debug()`	DEBUG (colored)	No	Default	Yes	Troubleshooting
`CONFIG.production('app.log')`	No	INFO	No	No	Production deployments
`CONFIG.silent()`	No	No	No	No	Silent operation

Examples:

CONFIG.exploring()  # Start exploring interactively
CONFIG.debug()  # See everything for troubleshooting
CONFIG.production('logs/prod.log')  # Production mode

Direct Control - Logging Only

For fine-grained control of logging without affecting other settings:

Methods: - enable_console(level='INFO', colored=True, stream=None) - enable_file(level='INFO', path='flixopt.log', max_bytes=10MB, backup_count=5) - disable() - Remove all handlers - set_colors(log_colors) - Customize level colors

Log Levels: Standard levels plus custom SUCCESS level (between INFO and WARNING): - DEBUG (10): Detailed debugging information - INFO (20): General informational messages - SUCCESS (25): Success messages (custom level) - WARNING (30): Warning messages - ERROR (40): Error messages - CRITICAL (50): Critical error messages

Examples:

import logging
from flixopt.config import CONFIG, SUCCESS_LEVEL

# Console and file logging
CONFIG.Logging.enable_console('INFO')
CONFIG.Logging.enable_file('DEBUG', 'debug.log')

# Use SUCCESS level with logger.log()
logger = logging.getLogger('flixopt')
CONFIG.Logging.enable_console('SUCCESS')  # Shows SUCCESS, WARNING, ERROR, CRITICAL
logger.log(SUCCESS_LEVEL, 'Operation completed successfully!')

# Or use numeric level directly
logger.log(25, 'Also works with numeric level')

# Customize colors
CONFIG.Logging.set_colors(
    {
        'INFO': 'bold_white',
        'SUCCESS': 'bold_green,bg_black',
        'CRITICAL': 'bold_white,bg_red',
    }
)

# Non-colored output
CONFIG.Logging.enable_console('INFO', colored=False)

Advanced Customization

For full control, use Python's standard logging or create custom formatters:

# Custom formatter
from flixopt.config import ColoredMultilineFormatter
import colorlog, logging

handler = colorlog.StreamHandler()
handler.setFormatter(ColoredMultilineFormatter(...))
logging.getLogger('flixopt').addHandler(handler)

# Or standard Python logging
import logging

logging.basicConfig(level=logging.DEBUG, format='%(asctime)s - %(levelname)s - %(message)s')

Note

Default formatters (MultilineFormatter and ColoredMultilineFormatter) provide pretty output with box borders for multi-line messages.

Functions¶

enable_console classmethod ¶

enable_console(level: str | int = 'INFO', colored: bool = True, stream: TextIO | None = None) -> None

Enable colored console logging.

Parameters:

Name	Type	Description	Default
`level`	`str \| int`	Log level (DEBUG, INFO, SUCCESS, WARNING, ERROR, CRITICAL or numeric level)	`'INFO'`
`colored`	`bool`	Use colored output if colorlog is available (default: True)	`True`
`stream`	`TextIO \| None`	Output stream (default: sys.stdout). Can be sys.stdout or sys.stderr.	`None`

Note

For full control over formatting, use logging.basicConfig() instead.

Examples:

# Colored output to stdout (default)
CONFIG.Logging.enable_console('INFO')

# Plain text output
CONFIG.Logging.enable_console('INFO', colored=False)

# Log to stderr instead
import sys

CONFIG.Logging.enable_console('INFO', stream=sys.stderr)

# Using logging constants
import logging

CONFIG.Logging.enable_console(logging.DEBUG)

enable_file classmethod ¶

enable_file(level: str | int = 'INFO', path: str | Path = 'flixopt.log', max_bytes: int = 10 * 1024 * 1024, backup_count: int = 5, encoding: str = 'utf-8') -> None

Enable file logging with rotation. Removes all existing file handlers!

Parameters:

Name	Type	Description	Default
`level`	`str \| int`	Log level (DEBUG, INFO, SUCCESS, WARNING, ERROR, CRITICAL or numeric level)	`'INFO'`
`path`	`str \| Path`	Path to log file (default: 'flixopt.log')	`'flixopt.log'`
`max_bytes`	`int`	Maximum file size before rotation in bytes (default: 10MB)	`10 * 1024 * 1024`
`backup_count`	`int`	Number of backup files to keep (default: 5)	`5`
`encoding`	`str`	File encoding (default: 'utf-8'). Use 'utf-8' for maximum compatibility.	`'utf-8'`

Note

For full control over formatting and handlers, use logging module directly.

Examples:

# Basic file logging
CONFIG.Logging.enable_file('INFO', 'app.log')

# With custom rotation
CONFIG.Logging.enable_file('DEBUG', 'debug.log', max_bytes=50 * 1024 * 1024, backup_count=10)

# With explicit encoding
CONFIG.Logging.enable_file('INFO', 'app.log', encoding='utf-8')

disable classmethod ¶

disable() -> None

Disable all flixopt logging.

Examples:

CONFIG.Logging.disable()

set_colors classmethod ¶

set_colors(log_colors: dict[str, str]) -> None

Customize log level colors for console output.

This updates the colors for the current console handler. If no console handler exists, this does nothing.

Parameters:

Name	Type	Description	Default
`log_colors`	`dict[str, str]`	Dictionary mapping log levels to color names. Colors can be comma-separated for multiple attributes (e.g., 'bold_red,bg_white').	required

Available colors

Basic: black, red, green, yellow, blue, purple, cyan, white
Bold: bold_red, bold_green, bold_yellow, bold_blue, etc.
Light: light_red, light_green, light_yellow, light_blue, etc.
Backgrounds: bg_red, bg_green, bg_light_red, etc.
Combined: 'bold_white,bg_red' for white text on red background

Examples:

# Enable console first
CONFIG.Logging.enable_console('INFO')

# Then customize colors
CONFIG.Logging.set_colors(
    {
        'DEBUG': 'cyan',
        'INFO': 'bold_white',
        'SUCCESS': 'bold_green',
        'WARNING': 'bold_yellow,bg_black',  # Yellow on black
        'ERROR': 'bold_red',
        'CRITICAL': 'bold_white,bg_red',  # White on red
    }
)

Note

Requires colorlog to be installed. Has no effect on file handlers.

Modeling ¶

Optimization modeling parameters.

Attributes:

Name	Type	Description
`big`	`int`	Large number for big-M constraints.
`epsilon`	`float`	Tolerance for numerical comparisons.
`big_binary_bound`	`int`	Upper bound for binary constraints.

Solving ¶

Solver configuration and default parameters.

Attributes:

Name	Type	Description
`mip_gap`	`float`	Default MIP gap tolerance for solver convergence.
`time_limit_seconds`	`int`	Default time limit in seconds for solver runs.
`log_to_console`	`bool`	Whether solver should output to console.
`log_main_results`	`bool`	Whether to log main results after solving.
`compute_infeasibilities`	`bool`	Whether to compute infeasibility analysis when the model is infeasible.
`capture_solver_log`	`bool`	Whether to route solver output through the `flixopt.solver` Python logger. When enabled, each solver log line is forwarded at INFO level to `logging.getLogger('flixopt.solver')`. This setting is independent of `log_to_console` — both can be active at the same time. .. note:: If `capture_solver_log` is `True` and `log_to_console` is `True` and the `flixopt` logger has a console handler, solver output will appear on the console twice (once natively, once via the logger). To avoid this, set `log_to_console = False` when capturing to a console logger.

Examples:

# Capture solver output to file only (no double console logging)
CONFIG.Solving.capture_solver_log = True
CONFIG.Solving.log_to_console = False  # avoid double console output
CONFIG.Logging.enable_file('INFO', 'flixopt.log')

# Capture through logger to console (disable native solver console)
CONFIG.Solving.capture_solver_log = True
CONFIG.Solving.log_to_console = False
CONFIG.Logging.enable_console('INFO')

# Native solver console only (no Python logger capture)
CONFIG.Solving.capture_solver_log = False
CONFIG.Solving.log_to_console = True

Plotting ¶

Plotting configuration.

Configure backends via environment variables: - Matplotlib: Set MPLBACKEND environment variable (e.g., 'Agg', 'TkAgg') - Plotly: Set PLOTLY_RENDERER or use plotly.io.renderers.default

Attributes:

Name	Type	Description
`default_show`	`bool`	Default value for the `show` parameter in plot methods.
`default_engine`	`Literal['plotly', 'matplotlib']`	Default plotting engine.
`default_dpi`	`int`	Default DPI for saved plots.
`default_facet_cols`	`int`	Default number of columns for faceted plots.
`default_sequential_colorscale`	`str`	Default colorscale for heatmaps and continuous data.
`default_qualitative_colorscale`	`str`	Default colormap for categorical plots (bar/line/area charts).

Examples:

# Configure default export and color settings
CONFIG.Plotting.default_dpi = 600
CONFIG.Plotting.default_sequential_colorscale = 'plasma'
CONFIG.Plotting.default_qualitative_colorscale = 'Dark24'

Carriers ¶

Default carrier definitions for common energy types.

Provides convenient defaults for carriers. Colors are from D3/Plotly palettes.

Predefined: electricity, heat, gas, hydrogen, fuel, biomass

Examples:

import flixopt as fx

# Access predefined carriers
fx.CONFIG.Carriers.electricity  # Carrier with color '#FECB52'
fx.CONFIG.Carriers.heat.color  # '#D62728'

# Use with buses
bus = fx.Bus('Grid', carrier='electricity')

Classes¶

Functions¶

reset `classmethod` ¶

reset() -> None

Reset all configuration values to defaults.

This resets modeling, solving, and plotting settings to their default values, and disables all logging handlers (back to silent mode).

Examples:

CONFIG.debug()  # Enable debug mode
# ... do some work ...
CONFIG.reset()  # Back to defaults (silent)

to_dict `classmethod` ¶

to_dict() -> dict

Convert the configuration class into a dictionary for JSON serialization.

Returns:

Type	Description
`dict`	Dictionary representation of the current configuration.

silent `classmethod` ¶

silent() -> type[CONFIG]

Configure for silent operation.

Disables all logging, solver output, and result logging for clean production runs. Does not show plots.

Examples:

CONFIG.silent()
# Now run optimizations with no output
result = optimization.solve()

debug `classmethod` ¶

debug() -> type[CONFIG]

Configure for debug mode with verbose output.

Enables console logging at DEBUG level and routes solver output through the flixopt.solver Python logger for full capture.

Examples:

CONFIG.debug()
# See detailed DEBUG logs and full solver output
optimization.solve()

exploring `classmethod` ¶

exploring() -> type[CONFIG]

Configure for exploring flixopt.

Enables console logging at INFO level and routes solver output through the flixopt.solver Python logger. Also enables browser plotting for plotly with showing plots per default.

Examples:

CONFIG.exploring()
# Perfect for interactive sessions
optimization.solve()  # Shows INFO logs and solver output
result.plot()  # Opens plots in browser

production `classmethod` ¶

production(log_file: str | Path = 'flixopt.log') -> type[CONFIG]

Configure for production use.

Enables file logging only (no console output), disables plots, and disables solver console output for clean production runs.

Parameters:

Name	Type	Description	Default
`log_file`	`str \| Path`	Path to log file (default: 'flixopt.log')	`'flixopt.log'`

Examples:

CONFIG.production('production.log')
# Logs to file, no console output
optimization.solve()

browser_plotting `classmethod` ¶

browser_plotting() -> type[CONFIG]

Configure for interactive usage with plotly to open plots in browser.

Sets plotly.io.renderers.default = 'browser'. Useful for running examples and viewing interactive plots. Does NOT modify CONFIG.Plotting settings.

Respects FLIXOPT_CI environment variable if set.

Examples:

CONFIG.browser_plotting()
result.plot()  # Opens in browser instead of inline

use_theme `classmethod` ¶

use_theme() -> type[CONFIG]

Activate the flixopt plotly theme as the default template.

Sets plotly.io.templates.default = 'plotly_white+flixopt'.

The 'flixopt' template is registered automatically on import with colorscales from CONFIG.Plotting. Call this method to make it the default for all plots.

Returns:

Type	Description
`type[CONFIG]`	The CONFIG class for method chaining.

Examples:

# Activate flixopt theme globally
CONFIG.use_theme()

# Or combine with other setup
CONFIG.notebook()  # Already calls use_theme() internally

# Per-figure usage (without setting global default)
fig.update_layout(template='plotly_white+flixopt')

notebook `classmethod` ¶

notebook() -> type[CONFIG]

Configure for Jupyter notebook environments.

Optimizes settings for notebook usage: - Sets plotly renderer to 'notebook' for inline display (unless PLOTLY_RENDERER env var is set) - Disables automatic plot.show() calls (notebooks display via repr_html) - Enables SUCCESS-level console logging - Disables solver console output for cleaner notebook cells

Note

The plotly renderer can be overridden by setting the PLOTLY_RENDERER environment variable (e.g., 'notebook_connected' for CDN-based rendering).

Examples:

# At the start of your notebook
import flixopt as fx

fx.CONFIG.notebook()

# Now plots display inline automatically
flow_system.stats.plot.balance('Heat')  # Displays inline

load_from_file `classmethod` ¶

load_from_file(config_file: str | Path) -> type[CONFIG]

Load configuration from YAML file and apply it.

Parameters:

Name	Type	Description	Default
`config_file`	`str \| Path`	Path to the YAML configuration file.	required

Returns:

Type	Description
`type[CONFIG]`	The CONFIG class for method chaining.

Raises:

Type	Description
`FileNotFoundError`	If the config file does not exist.

Examples:

CONFIG.load_from_file('my_config.yaml')

Example YAML file:

config_name: my_project
modeling:
    big: 10000000
    epsilon: 0.00001
solving:
    mip_gap: 0.001
    time_limit_seconds: 600
plotting:
    default_engine: matplotlib
    default_dpi: 600

flixopt.config ¶

Classes¶

MultilineFormatter ¶

Functions¶

format ¶

ColoredMultilineFormatter ¶

Functions¶

format ¶

CONFIG ¶

Classes¶

Logging ¶

Functions¶

Modeling ¶

Solving ¶

Plotting ¶

Carriers ¶

Classes¶

Functions¶

reset classmethod ¶

to_dict classmethod ¶

silent classmethod ¶

debug classmethod ¶

exploring classmethod ¶

production classmethod ¶

browser_plotting classmethod ¶

use_theme classmethod ¶

notebook classmethod ¶

load_from_file classmethod ¶

reset `classmethod` ¶

to_dict `classmethod` ¶

silent `classmethod` ¶

debug `classmethod` ¶

exploring `classmethod` ¶

production `classmethod` ¶

browser_plotting `classmethod` ¶

use_theme `classmethod` ¶

notebook `classmethod` ¶

load_from_file `classmethod` ¶