`mass_fraction_calculator.py`¶

Constants¶

Name	Value
`_TOKEN_RE`	`re.compile('([A-Z][a-z]?\\|\\(\\|\\))(\\d*(?:\\.\\d+)?)')`
`_ELEMENT_ORDER_RE`	`re.compile('([A-Z][a-z]?)')`

Database loader for materials from CSV with signature-based lookup.

Method	Signature	Description
`__init__`	`(self)`
`auto_load_csv`	`(self) → bool`	Try to load CSV from standard locations, preferring trimmed/compressed versions.
`load_csv`	`(self, csv_path: str \\| Path) → bool`	Load CSV and build signature-based indices.
`_signature_for_formula`	`(self, formula: str) → str`
`get_data_by_formula_or_signature`	`(self, formula: str) → list[dict]`
`best_density_for_formula`	`(self, formula: str) → float`
`best_url_for_formula`	`(self, formula: str) → str`
`get_compounds_for_element`	`(self, element: str) → list[dict]`	Get one entry per canonical formula for initial browsing.
`get_variants_for_formula`	`(self, formula: str) → list[dict]`	Get ALL polymorphs/structures for a given formula.
`get_material_data`	`(self, formula: str) → list[dict]`

Editable combobox for chemical formulas with debounced filtering.

Method	Signature	Description
`__init__`	`(self, element: str, csv_database: CSVCompoundDatabase, tracked_elemen`
`_setup_compounds`	`(self)`	Build the full item list but only load a capped subset into the widget.
`_rebuild_items`	`(self, items: list[dict])`	Replace dropdown items, blocking ALL signals to prevent recursion.
`_do_filter`	`(self)`	Actually perform the filter (called by debounce timer).
`filter_to_formula`	`(self, user_canon_formula: str)`	Show all polymorphs/structures for the confirmed formula.
`reset_items`	`(self)`	Restore the capped default list.
`_set_editor_text`	`(self, text: str)`	Set the lineEdit text without triggering any slots.
`current_formula`	`(self) → str`
`_on_text_changed`	`(self, text: str)`	Debounce: restart timer on every keystroke, filter when typing pauses.
`_on_item_activated`	`(self, index: int)`
`_on_editing_finished`	`(self)`

Compact widget with checkbox + label for sample list.

Method	Signature	Description
`__init__`	`(self, sample_name: str, parent=None)`
`is_checked`	`(self) → bool`
`set_checked`	`(self, checked: bool)`

Only accept positive floats when editing density cells.

Mass fraction calculator with sample selection and molecular weight calculations.

Method	Signature	Description
`__init__`	`(self, selected_isotopes: dict, periodic_table_widget, parent=None)`
`apply_theme`	`(self)`	Apply the currently active theme palette to this dialog.
`closeEvent`	`(self, event)`	Disconnect theme signal so we don't leak slots on closed dialogs.
`_build_stylesheet`	`(self) → str`	Dark/light aware stylesheet for the whole dialog.
`_refresh_db_status_style`	`(self)`
`_refresh_apply_button_style`	`(self)`
`_setup_ui`	`(self)`
`_build_sample_panel`	`(self) → QGroupBox`
`_build_header`	`(self) → QHBoxLayout`
`_build_table`	`(self)`
`_build_buttons`	`(self) → QHBoxLayout`
`_populate_table`	`(self)`
`_make_readonly_item`	`(text: str) → QTableWidgetItem`
`_element_data`	`(self, symbol: str) → dict \\| None`
`_current_formula`	`(self, row: int) → str`
`_calc_mass_fraction`	`(self, row: int, formula: str)`
`_calc_molecular_weight`	`(self, row: int, formula: str)`
`_on_compound_selected`	`(self, row: int, formula: str, density_csv: float)`
`_highlight_tracked`	`(self, row: int, formula: str)`	Set a tooltip showing which elements in the compound are being tracked.
`_calculate_all`	`(self)`
`_reset_to_default`	`(self)`
`_select_all_samples`	`(self)`
`_select_no_samples`	`(self)`
`_get_selected_samples`	`(self) → list[str]`
`_save_state`	`(self)`
`_restore_previous_state`	`(self)`
`_manual_load_csv`	`(self)`
`_open_structure`	`(self, row: int)`
`_apply_mass_fractions`	`(self)`
`closeEvent`	`(self, event)`
`reject`	`(self)`

Function	Signature	Description
`_parse_formula_to_counts`	`(formula: str) → dict`	Parse a chemical formula string into {element: integer_count}.
`_safe_int`	`(s: str, *, default: int=1) → int`	Convert a numeric string to a positive int, rounding floats.
`_element_order_in_formula`	`(formula: str) → list[str]`	Return elements in the order they first appear in formula.
`_reduce_counts`	`(counts: dict) → dict`	Divide all counts by their GCD to get the empirical formula.
`_signature_from_counts`	`(counts: dict) → str`	Order-independent canonical key for matching equivalent formulas.
`_join_formula_from_counts`	`(counts: dict, prefer_order: list[str] \\| None=None) → str`	Build a human-readable formula string from counts.
`canonicalize_preserve_user_order`	`(formula: str) → str`	Reduce stoichiometry but preserve the user's element order.