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# Module: safe.storage.raster

Class Raster

class `safe.storage.raster.``Raster`(data=None, projection=None, geotransform=None, name=None, keywords=None, style_info=None)

  Internal representation of raster data

  `copy`()

    Return copy of raster layer

    This copy will be equal to self in the sense defined by __eq__

  `get_bins`(N=10, quantiles=False)

    Get N values between the min and the max occurred in this dataset.

    Return sorted list of length N+1 where the first element is min and the last is max. Intermediate values depend on the keyword quantiles: If quantiles is True, they represent boundaries between quantiles. If quantiles is False, they represent equidistant interval boundaries.

  `get_bounding_box`()

    Get bounding box coordinates for raster layer

    Note:
      Format is [West, South, East, North]
  `get_data`(nan=True, scaling=None, copy=False)

    Get raster data as numeric array

    Args:
      - nan: Optional flag controlling handling of missing values.

          If nan is True (default), nodata values will be replaced with numpy.nan If keyword nan has a numeric value, nodata values will be replaced by that value. E.g. to set missing values to 0, do get_data(nan=0.0)

      - scaling: Optional flag controlling if data is to be scaled

          if it has been resampled. Admissible values are False: data is retrieved without modification. True: Data is rescaled based on the squared ratio

          > between its current and native resolution. This is typically required if raster data represents a density such as population per km^2

          None: The behaviour will depend on the keyword

            “population” associated with the layer. If it is “density”, scaling will be applied otherwise not. This is the default.

          scalar value: If scaling takes a numerical scalar value,

            that will be use to scale the data

    - copy (optional): If present and True return copy
    Note:
      Scaling does not currently work with projected layers. See issue #123
  `get_extrema`()

    Get min and max from raster Note:

    > If raster has a nominated no_data value, this is ignored.

    Returns:
      min, max
  `get_geometry`()

    Return longitudes and latitudes (the axes) for grid.

    Note:

      Return two vectors (longitudes and latitudes) corresponding to grid. The values are offset by half a pixel size to correspond to pixel registration.

      I.e. If the grid origin (top left corner) is (105, 10) and the resolution is 1 degrees in each direction, then the vectors will take the form

      longitudes = [100.5, 101.5, ..., 109.5] latitudes = [0.5, 1.5, ..., 9.5]

  `get_geotransform`(copy=False)

    Return geotransform for this raster layer

    Returns: * geotransform: 6 digit vector

    > (top left x, w-e pixel resolution, rotation,

    >   top left y, rotation, n-s pixel resolution).

    >   See e.g. http://www.gdal.org/gdal_tutorial.html

    - copy (optional): If present and True return copy
  `get_nodata_value`()

    Get the internal representation of NODATA

    Note:
      If the internal value is None, the standard -9999 is assumed
  `get_resolution`(isotropic=False, native=False)

    Get raster resolution as a 2-tuple (resx, resy)

    Args:
      - isotropic: If True, verify that dx == dy and return dx

          If False return 2-tuple (dx, dy)

      - native: Optional flag. If True, return native resolution if

          available. Otherwise return actual.

  `read_from_file`(filename)

    Read and unpack raster data

  `to_vector_layer`()

    Convert raster grid to vector point data

    Returns:
      a vector layer object with data points corresponding to grid points. The order is row-major which means that the x (longitude) direction is varying the fastest.
  `to_vector_points`()

    Convert raster grid to vector point data

    Returns:
      - coordinates: Nx2 array of x, y (lon, lat) coordinates
      - values: N array of corresponding grid values
  `write_to_file`(filename)

    Save raster data to file

    Args:
      - filename: filename with extension .tif

    Gdal documentation at: http://www.gdal.org/classGDALRasterBand.html

This module forms part of the InaSAFE tool.

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