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README.md

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+# MipMap-1d
+
+This Rust crate provides a small data structure that constructs and holds your 1-dimensional mipmaps.
+MipMaps are just downsampled versions of your vector.
+Each level is only half the size of a previous level.
+Therefore, the entire data structure takes approximately 2x the size of initial data in memory.
+
+The downsampling is currently performed by averaging the pairs of elements (see example below).
+New ways might be introduced in later versions.
+
+The crate currently works with all major numeric types (thanks to `num-traits` crate).
+
+This can be used, for example, in plots.
+If you have a large number of points (lets say, 10M), you clearly can not draw them all on the screen at once.
+Also, drawing so many requires a lot of computational resources.
+
+What you can do is to use 1d MipMap: you make several downsamples, and choose which one you want to display depending on a zoom level.
+The more you zoom in, the 'higher resolution' data you display.
+
+## Example
+
+```rust
+use mipmap_1d::MipMap1D;
+
+let data = vec![2, 4, 6, 8, 9];
+let mipmap = MipMap1D::new(data);
+assert_eq!(mipmap.num_levels(), 4);
+assert_eq!(*mipmap.get_level(0).unwrap(), [2, 4, 6, 8, 9]);
+assert_eq!(*mipmap.get_level(1).unwrap(), [3, 7, 9]);
+assert_eq!(*mipmap.get_level(2).unwrap(), [5, 9]);
+assert_eq!(*mipmap.get_level(3).unwrap(), [7]);
+assert_eq!(mipmap.get_level(4), None);
+```
+
+## Contributing
+
+Currently, the only idea for improvement is to introduce new averaging methods that are used in signal processing.
+Check issue #1 for details.