[arrow] branch master updated: ARROW-2777: [JS] Friendlier onboarding readme

[we...@apache.org]

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The following commit(s) were added to refs/heads/master by this push:
     new 16bbdd4  ARROW-2777: [JS] Friendlier onboarding readme
16bbdd4 is described below

commit 16bbdd47a73782588090872adf54a11b9c95aa6e
Author: lmeyerov <lm...@gmail.com>
AuthorDate: Wed Jul 25 14:03:25 2018 -0400

    ARROW-2777: [JS] Friendlier onboarding readme
    
    -- Link slack,  tutorials, unit tests
    -- Add example of creating a Table from pure JS
    
    Author: lmeyerov <lm...@gmail.com>
    
    Closes #2200 from lmeyerov/patch-3 and squashes the following commits:
    
    dda23d35 <lmeyerov> fix(remove slack from js docs)
    a2ddcb17 <lmeyerov> docs(js - getting started)
---
 js/README.md | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/js/README.md b/js/README.md
index 76fae6d..b02ff34 100644
--- a/js/README.md
+++ b/js/README.md
@@ -39,6 +39,7 @@ Apache Arrow is the emerging standard for large in-memory columnar data ([Spark]
 
 # Usage
 
+
 ## Get a table from an Arrow file on disk (in IPC format)
 
 ```es6
@@ -83,6 +84,31 @@ console.log(table.toString());
 */
 ```
 
+## Create a Table from JavaScript arrays
+
+```es6
+const fields = [{
+        name: 'precipitation',
+        type: { name: 'floatingpoint', precision: 'SINGLE'},
+        nullable: false, children: []
+    }, {
+        name: 'date',
+        type: { name: 'date', unit: 'MILLISECOND' },
+        nullable: false, children: []
+    }];
+const rainAmounts = Array.from({length: LENGTH}, () => Number((Math.random() * 20).toFixed(1)));
+const rainDates = Array.from({length: LENGTH}, (_, i) => Date.now() - 1000 * 60 * 60 * 24 * i);
+
+const LENGTH = 2000;
+const rainfall = arrow.Table.from({
+  schema: { fields: fields },
+  batches: [{ 
+    count: LENGTH,
+    columns: [
+      {name: "precipitation", count: LENGTH, VALIDITY: [], DATA: rainAmounts },
+      {name: "date",          count: LENGTH, VALIDITY: [], DATA: rainDates } ] }] })
+```
+
 ## Load data with `fetch`
 
 ```es6
@@ -158,6 +184,12 @@ Index,   origin_city
 */
 ```
 
+# Tutorials and examples
+
+* [JavaScript Introduction to Arrow][5]
+* [Manipulating flat arrays arrow-style][6]
+* [/js/test/unit](https://github.com/apache/arrow/tree/master/js/test/unit) - Unit tests for Table and Vector
+
 # Getting involved
 
 See [develop.md](https://github.com/apache/arrow/blob/master/develop.md)
@@ -242,3 +274,5 @@ Full list of broader Apache Arrow [projects & organizations](https://github.com/
 [2]: https://github.com/apache/arrow/tree/master/format
 [3]: https://issues.apache.org/jira/browse/ARROW
 [4]: https://github.com/apache/arrow
+[5]: https://beta.observablehq.com/@theneuralbit/introduction-to-apache-arrow
+[6]: https://beta.observablehq.com/@lmeyerov/manipulating-flat-arrays-arrow-style