hazimp.raster

Manipulate raster data.

Module Contents

Classes

Raster

A simple class to describe a raster.

Functions

files_raster_data_at_points(lon, lat, files, scaling_factor=None)

Get data at lat lon points, based on a set of files

recalc_max(max_extent, extent)

Given an extent and a maximum extent modify maximum extent so
class hazimp.raster.Raster(filename, upper_left_x, upper_left_y, x_pixel, y_pixel, no_data_value, x_size, y_size)

Bases: object

A simple class to describe a raster.

classmethod from_file(cls, filename)

Load a file in a raster file format known to GDAL. Note, image must be ‘North up’.

Parameters:

filename – The raster file path string.

Returns:

A Raster instance.

raster_data_at_points(self, lon, lat, scaling_factor=None)

Get data at lat lon points of the raster.

Parameters:

  • lon – A 1D array of the longitude of the points.

  • lat – A 1D array of the latitude of the points.

  • scaling_factor – An optional scaling factor to apply to the values.

Returns:

A numpy array, First dimension being the points/sites.

extent(self)

Return the extent, in lats and longs of the raster.

Returns:

min_long, min_lat, max_long, max_lat

hazimp.raster.files_raster_data_at_points(lon, lat, files, scaling_factor=None)

Get data at lat lon points, based on a set of files

Parameters:

  • files – A list of files.

  • lon – A 1D array of the longitude of the points.

  • lat – A 1d array of the latitude of the points.

  • scaling_factor – An optional scaling factor to apply to the values.

Returns:

reshaped_data, max_extent reshaped_data: A numpy array, shape (sites, hazards) or shape (sites), for one hazard. max_extent: [min_long, min_lat, max_long, max_lat] A rectange covering the extents of all of the loaded rasters.

hazimp.raster.recalc_max(max_extent, extent)

Given an extent and a maximum extent modify maximum extent so it covers the extent area.

Both parameters describe a rectangle;

[min_long, min_lat, max_long, max_lat]

Parameters:

  • max_extent – A list describing a rectangular area.

  • extent – A tuple/list describing the area that must be covered by max_extent.