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README.md

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 # plotbd
 A tool to plot bifurcation diagrams using Node.js and Gnuplot.
+
+
+## Installation
+
+```bash
+npm install plotbd
+```
+
+## Usage
+
+```js
+const plotbd = require('plotbd');
+
+/*
+The map should have the following pattern
+- The current state x(n) as the first argument.
+- The control parameter (r) as the second one.
+- return the next state x(n+1)
+*/
+function logisticMap (x, r) {
+  return r * x * (1 - x);
+}
+
+plotbd(logisticMap, {
+  x0: 0.4, // [required] the initial state
+  rValues: [0.1, 3.99, 1000], // [required] the control parameter [min, max, numberOfValues]
+  iterations: 500, // [optional] number of iterations to do for a each r value
+  density: 100 // [optional] number of "x" values to plot per "r" value.
+});
+```
+
+![bifurcation-diagram](https://user-images.githubusercontent.com/11301627/59551650-7a290e00-8f74-11e9-8a6c-42120a28053c.png)
+
+## Notes
+
+- `density` must always be less than `iterations` because the `x` values to keep are part of iterations.
+- increasing the number of `r` values `rValues[2]` and `density` will enhance the bifurcation diagram plot by adding more details. But, it will decrease the performance on the other hand.