Updated the latest version details and features implimented

CHANGELOG.md

@@ -4,6 +4,33 @@ Changelog of postpic
 current master
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+v0.6
+----
+
+2023-01-23
+
+This is the first version which is compatible with `Smilei` PIC (https://smileipic.github.io/Smilei/) data format. The addon datareader code is `smileih5.py` (https://github.com/skuschel/postpic/blob/dev/postpic/datareader/smileih5.py). Might be slower in runtime compared to `happi` module, a default data processing module for smilei (https://github.com/SmileiPIC/Smilei/tree/master/happi). But soon will be optimised.
+
+**Highlights**
+
+* Quick and efficient way of importing h5file using index file method, so that multiple .h5 files can be imported at the same time.
+* Added support for files written by the smilei `version v4.8` (https://github.com/SmileiPIC/Smilei/releases/tag/v4.8).
+* Azimuthal Mode decomposition technique is implimented.
+* Can extract field data from both Cartesian and Azimuthal mode decomposed fields.
+
+**Incompatible adjustments to previous version**
+
+* The `data()`, `gridoffset()`, `gridpoints()`, `gridspacing()` and `_modeexpansion_naiv()` methods were altered from `openPMDh5.py` standards format due to different data dumping format of SmileiPIC.
+* Since the Azimuthal mode field data dump format were different from FBpic dump format, a new method `_getExpanded()` is introduced to structure the data dumped by SmileiPIC into an array of complex numbers which is then fed into `_modeexpansion_naiv()` method.
+
+**Other improvements and new features**
+
+* The fields (`both cartesian and Azimuthal mode`) can be accessed by method `data(key, **kwargs)`, the keys are in the format `El`, `Bx`, `Rho` etc.,
+* The species data also can be accessed by `x`, `Px`, `q`, `w` etc.,
+* Azimuthal Mode decomposition technique is implimented, by mentioning theta (either single value or list of angles) as kwargs in `data` method.
+* Gridoffset, gridpoints and gridspacing data can be accessed using `gridoffset(key, axis)`, `gridpoints(key, axis)` and `gridspacing(key, axis)` methods respectively.
+* List of Azimuthal fields names and Modes available in the dump can be obtained using `_listAMmodes()` method.
+
 
 v0.5
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