Metview

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- added helper functions to aid automatic conversion from Macro to Python
- added support for reading PNG files
- added string() function from Metview
- fixed warning message in select() method with pandas 2.2

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- Added arguments() function to mimic the behaviour of the Macro function of the same name
- Fixed case of mean(dim=...) where the input fieldset is not a complete hypercube

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- Fieldset function stdev() now accepts 'dim' argument to compute over given dimension
- added new function plot_xs_avg() to provide high-level plotting interface for average cross sections
- Fixed issue where functions that take numpy arrays as input did not work properly with multi-dimensional arrays

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- fixed memory leaks when passing strings, numbers and dates from the binary layer to the Python layer

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- Fieldset functions mean() and sum() now accept 'dim' argument to compute over given dimension
- function gallery.load_dataset() now downloads from a new server
- added new functions smooth_n_point() and smooth_gaussian() to perform spatial smoothing on fieldsets with lat-lon grids
- added new function convolve() to perform spatial 2D convolution on fieldsets with lat-lon grids

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- add 'reverse' and/or operators between Fieldsets and bools (e.g. 'True & my_fieldset')
- fixed issue where automatic indexing of a dataset fails