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README.md

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+# scaling
+
+Convert quantities between model and prototype scale using Froude similarity.
+
+## Installation
+
+```
+pip install git+http://git.wrl.unsw.edu.au:3000/danh/scaling.git
+```
+
+## Usage
+
+```sh
+>>> from scaling import Froude
+>>> froude = FroudeConverter()
+
+>>> # Convert model value of 200 mm to prototype value (m) with scale of 10
+>>> froude.model_to_proto(200, length_scale=10, input_unit='mm', target_unit='m')
+2.0
+
+>>> # Get Froude scaling exponent for quantities of time
+>>> froude.scaling_exponent('s')
+0.5
+
+>>> # Get length, mass and time dimensions for quantities of force
+>>> froude.dimensions('N')
+'L^1 M^1 T^-2'
+```
+
+`scaling` uses `pint` for unit and dimension conversions. `pint` is able to interpret a wide range of different input units.
+
+```sh
+>>> # Convert water head model value (mm) to prototype pressure value (kPa)
+>>> froude.model_to_proto(10, length_scale=100, 'mm.H20', 'kPa')
+9.80665
+
+>>> # Make sure gravity remains constant in Froude scaling
+>>> froude.proto_to_model(1, 10, 'gravity', 'meter/second/second')
+9.80665
+```