nctoolkit.DataSet.subtract

DataSet.subtract(self, x=None, var=None)

Subtract from a dataset This will subtract a constant, another dataset or a netCDF file from the dataset.

Parameters
  • x (int, float, DataSet or netCDF file) – An int, float, single file dataset or netCDF file to subtract from the dataset. If a dataset or netCDF is supplied this must only have one variable, unless var is provided. The grids must be the same.

  • var (str) – A variable in the x to use for the operation

Examples

If you wanted to subtract 10 from all variables in a dataset, you would do the following:

>>> ds.subtract(10)

To substract the values in a dataset ds2 from those in a dataset ds1, you would do the following:

>>> ds1.subtract(ds2)

Grids in the datasets must match. Division will occur in matching timesteps in ds1 and ds2 if there are matching timesteps. If there is only 1 timestep in ds2, then the data from that timestep in ds2 will be subtracted from the data in all timesteps in ds1.

Subtracting of the data from another netCDF file will work in the same way:

>>> ds1.subtract("example.nc")