Nctoolkit

This minor release adds new features. Code written for prior releases are compatible with this release.

Improved temporal statistics

Calculating temporal statistics has been streamlined. Temporal methods are now prefixed with the letter t, and accept grouping options. So, for example, `data.tmean(["year", "month"])` will calculate the mean value for each month in each year.

Mild enhancements to methods

The `select` and `shift` methods have been tweaked to make life slightly easier for users, and allow partial matches for args. For example `data.shift(hours = 1)` and `data.shift(hour = 1)` are both valid.

open_url is now able to keep attempting to download files for a set period until complete.

open_thredds now has a wait option to stop

Bug fixes

Issues related to user specified temp folders not being set are now fixed.

Renamings and deprecations

Existing temporal statistics methods, such as mean, max etc., have now been deprecated and the new methods tmean etc. should be used.

`vertical_cum_sum` has been renamed to `vertical_cumsum`. `vertical_cum_sum` is now deprecated.

Plotting improvements

Automatic plotting now relies on the new ncplot package. Plotting is now greatly enhanced and includes automatic coastlines.

Mild enhancements to methods

- Users can now specify the temporary folder to be used by nctoolkit with nctoolkit.options(temp_dir = x)


Deprecations and renaming
- `var` is now called `variance` to be more consistent with python. `var` is deprecated and will be removed early 2021.

bug fixes

- append was not working properly for ensembles. Now fixed

This release has some new methods, a minor bug fix and some enhancements. It is fully compatible with code written for the previous release.
New methods

1. `centre`. This method let's you work out the latitudinal and longitudinal centre.
2. `strip_variable`. This method let's you removed associated variables from variables.
3. `resample_grid`. This method let's you resample grids.
4. `format`. This method let's you change the format of dataset NetCDF files.

Deprecations

`write_nc` has been replaced by `to_nc`. `write_nc` will be replaced in a few months.

Bug fixes

1. `cell_areas` was throwing errors for CDO 1.9.6. This is now fixed.

Enhancements

Improvements have been made to `plot` to improve handling of non-spatial datasets. Plotting development is now separated into a new package ncplot. This will become a dependency in an upcoming version of nctoolkit. Read about it [here](https://github.com/pmlmodelling/ncplot).

New methods

- `annual_sum`: a method for calculating the annual sums
- `daily_mean` etc.: methods for calculating daily statistical values
- `select`: a wraper around existing select methods such as `select_year` and `select_variables`
- `shift_months` and `shift_years`: methods to shift time by months and years
- `shift`: a wrapper around existing shift methods

Deprectations

- `select_season` is now called `select_seasons`. `select_season` has been deprecated and will be removed in a few months.
- `select_timestep` is now called `select_timesteps`. `select_timestep` has been deprecated and will be removed in a few months.

Minor fixes

- `plot` was throwing errors when plotting time series graphs for some types of data. This is now fixed.

macOS support
This release adds support for macOS.

New methods

Meridonial statistics can be calculated using `meridonial_mean` etc.

`open_url` is a version of open_dataset for urls.

`open_thredds` is a version of open_dataset for thredds.

Minor update that is compatible with the prior 0.1.4 release.

Method improvement

`cor_space` and `cor_time` methods for comparing datasets now work for multiple variables.