* module `io_ops` renamed to `io`,
* the refactored function `read_point_data` (old) into `read_txt`, new functions to read csv and blocks data,
* the new objects to store block data and its point-support: `Blocks` and `PointSupport`,
* Kriging is now supported by **functions**, not by classes, to speed up some calculations. In the future, classes will be introduced again,
* user has much more control over the variograms development. `ExperimentalVariogram` class calculates *variance*, *covariance*, and *semivariance*, has own plotting function. `TheoreticalVariogram` has more models to fit, and gives more control to search for the best fit - the algorithm searches over ranges and sills. Nugget is still fixed,
* module `pipelines` has the function for the block data smoothing (area-to-point Poisson Kriging), the class for block data filtering (area-to-area Poisson Kriging), the kriging comparison class, and method to download sample air pollution data,
* there are many small changes and API transformations... The package is faster and more stable,
* it works with Python 3.7, 3.8, 3.9, and 3.10,
* Ordinary and Simple Kriging of large datasets may be performed in parallel,
* the package has a few warnings and raises custom errors,
* `setup.py` is removed, now package installs from `setup.cfg`,
* data structures are more complex, but they allow user to be more flexible with an input.
2021-12-31
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