Update README.md

README.md

@@ -6,4 +6,42 @@
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-simple ndviewer
+Simple python nd array viewer:
+
+```python
+from qtpy import QtWidgets
+from ndv import NDViewer
+from skimage import data
+
+qapp = QtWidgets.QApplication([])
+v = NDViewer(data.cells3d())
+v.show()
+qapp.exec()
+```
+
+![Montage](https://github.com/tlambert03/ndv/assets/1609449/712861f7-ddcb-4ecd-9a4c-ba5f0cc1ee2c)
+
+## `NDViewer`
+
+Simple, fast-loading, asynchronous, n-dimensional viewer for Qt.  Minimal dependencies.
+
+- supports arbitrary number of dimensions, with 2D/3D view canvas, and sliders for all non-visible dims
+- sliders support integer as well as slice (range)-based slicing
+- colormaps provided by [cmap](https://github.com/tlambert03/cmap)
+- supports [vispy](https://github.com/vispy/vispy) and [pygfx](https://github.com/pygfx/pygfx) backends
+- supports any numpy-like duck arrays, with special support for features in:
+  - `xarray.DataArray`
+  - `dask.array.Array`
+  - `tensorstore.TensorStore`
+  - `zarr`
+  - `dask`
+
+## Installation
+
+The only required dependencies are `numpy` and `superqt[cmap,iconify]`.
+You will also need a Qt backend (PyQt or PySide) and one of either
+[vispy](https://github.com/vispy/vispy) or [pygfx](https://github.com/pygfx/pygfx):
+
+```python
+pip install ndv[pyqt,vispy]
+```