Virtual Table Model#

Virtual table model for efficient data display.

This module provides a virtual table model that can handle large datasets efficiently by loading data on-demand and caching frequently accessed items.

VirtualTableModel(*args, **kwargs)

Virtual table model for handling large datasets efficiently.

VirtualDataProvider()

Abstract base class for data providers in virtual table models.

MDAVirtualDataProvider(scan_dict[, cache_size])

Data provider for MDA file data in virtual table models.
class mdaviz.virtual_table_model.MDAVirtualDataProvider(scan_dict: dict[str, Any], cache_size: int = 1000)[source]#

Data provider for MDA file data in virtual table models.

This provider handles loading and caching of MDA file data for display in virtual table models.

clear_cache() → None[source]#

Clear the data cache.

get_column_count() → int[source]#

Get the total number of columns.

get_column_headers() → list[str][source]#

Get the column headers.

get_data(row: int, column: int) → Any[source]#

Get data for a specific cell.

get_memory_usage_mb() → float[source]#

Get the approximate memory usage in megabytes.

Returns:

float: Memory usage in MB

get_row_count() → int[source]#

Get the total number of rows.

is_data_loaded(row: int) → bool[source]#

Check if data for a specific row is loaded.

Parameters:

row (int): Row index

Returns:

bool: True if data is loaded, False otherwise

load_data_range(start_row: int, end_row: int) → None[source]#

Load data for a specific range of rows.

For MDA data, this is a no-op since all data is already loaded in the scan_dict. This method is provided for interface compatibility.

Parameters:

start_row (int): Starting row index (inclusive) end_row (int): Ending row index (exclusive)

class mdaviz.virtual_table_model.VirtualDataProvider[source]#

Abstract base class for data providers in virtual table models.

This class defines the interface that data providers must implement to work with the VirtualTableModel.

clear_cache() → None[source]#

Clear any cached data.

This method should clear any internal caches maintained by the data provider to free up memory.

get_column_count() → int[source]#

Get the total number of columns in the dataset.

Returns:

int: Total number of columns

get_column_headers() → list[str][source]#

Get the column headers.

Returns:

list[str]: List of column header strings

get_data(row: int, column: int) → Any[source]#

Get data for a specific cell.

Parameters:

row (int): Row index column (int): Column index

Returns:

Any: Data for the specified cell

get_row_count() → int[source]#

Get the total number of rows in the dataset.

Returns:

int: Total number of rows

is_data_loaded(row: int) → bool[source]#

Check if data for a specific row is loaded.

Parameters:

row (int): Row index

Returns:

bool: True if data is loaded, False otherwise

load_data_range(start_row: int, end_row: int) → None[source]#

Load data for a specific range of rows.

This method is called by the virtual table model when it needs to load data for a visible range of rows.

Parameters:

start_row (int): Starting row index (inclusive) end_row (int): Ending row index (exclusive)

class mdaviz.virtual_table_model.VirtualTableModel(*args: Any, **kwargs: Any)[source]#

Virtual table model for handling large datasets efficiently.

This model implements virtual scrolling by loading data on-demand and only keeping a subset of the data in memory at any time.

Attributes:

data_provider (VirtualDataProvider): Provider for the actual data page_size (int): Number of rows to load per page preload_pages (int): Number of pages to preload

_ensure_data_loaded(row: int) → None[source]#

Ensure that data for a specific row is loaded.

Parameters:

row (int): Row index

clear_cache() → None[source]#

Clear the loaded data cache.

columnCount(parent=None)[source]#

Get the total number of columns.

data(index, role=0)[source]#

Get data for a specific index and role.

headerData(section, orientation, role=0)[source]#

Get header data for the table.

rowCount(parent=None)[source]#

Get the total number of rows.

set_visible_range(start_row: int, end_row: int) → None[source]#

Set the currently visible range of rows.

This method is called by the view to inform the model about which rows are currently visible, allowing for preloading.

Parameters:

start_row (int): Starting row index (inclusive) end_row (int): Ending row index (exclusive)