From cd768292627e659fa17231a5a818ceb6cd005ef1 Mon Sep 17 00:00:00 2001
From: atomiks <sprytex@gmail.com>
Date: Wed, 13 Dec 2017 21:50:16 +1100
Subject: [PATCH 1/4] Create percentile.md

https://www.easycalculation.com/statistics/percentile-rank.php

Feel free to try and one-linerify it if possible, lol
---
 snippets/percentile.md | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 snippets/percentile.md

diff --git a/snippets/percentile.md b/snippets/percentile.md
new file mode 100644
index 000000000..70d303d1a
--- /dev/null
+++ b/snippets/percentile.md
@@ -0,0 +1,18 @@
+### Percentile
+
+Calculate how many numbers are below the value and how many are the same value and
+apply the percentile formula.
+
+```js
+const percentile = (arr, val) => {
+  let below = 0, same = 0;
+  
+  for (const number of arr) {
+    if (number < val) below++;
+    if (number === val) same++;
+  }
+  
+  return 100 * (below + (0.5 * same)) / arr.length;
+};
+// percentile([1,2,3,4,5,6,7,8,9,10], 6) -> 55
+ ```

From 19cff66dd43adc506151cb7a2a0e1d91a47eb182 Mon Sep 17 00:00:00 2001
From: atomiks <sprytex@gmail.com>
Date: Wed, 13 Dec 2017 22:18:49 +1100
Subject: [PATCH 2/4] Update percentile.md

---
 snippets/percentile.md | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/snippets/percentile.md b/snippets/percentile.md
index 70d303d1a..4be44782a 100644
--- a/snippets/percentile.md
+++ b/snippets/percentile.md
@@ -1,18 +1,10 @@
 ### Percentile
 
-Calculate how many numbers are below the value and how many are the same value and
+Use `Array.filter()` to calculate how many numbers are below the value and how many are the same value and
 apply the percentile formula.
 
 ```js
-const percentile = (arr, val) => {
-  let below = 0, same = 0;
-  
-  for (const number of arr) {
-    if (number < val) below++;
-    if (number === val) same++;
-  }
-  
-  return 100 * (below + (0.5 * same)) / arr.length;
-};
+const percentile = (arr, val) =>
+  100 * (arr.filter(v => v < val).length + 0.5 * arr.filter(v => v === val).length) / arr.length;
 // percentile([1,2,3,4,5,6,7,8,9,10], 6) -> 55
  ```

From 32d182d1f66bf73b85ad7c0c2f7b142f51699cf3 Mon Sep 17 00:00:00 2001
From: atomiks <sprytex@gmail.com>
Date: Wed, 13 Dec 2017 22:23:11 +1100
Subject: [PATCH 3/4] use reduce magic

---
 snippets/percentile.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/snippets/percentile.md b/snippets/percentile.md
index 4be44782a..271a90599 100644
--- a/snippets/percentile.md
+++ b/snippets/percentile.md
@@ -4,7 +4,7 @@ Use `Array.filter()` to calculate how many numbers are below the value and how m
 apply the percentile formula.
 
 ```js
-const percentile = (arr, val) =>
-  100 * (arr.filter(v => v < val).length + 0.5 * arr.filter(v => v === val).length) / arr.length;
+const percentile = (arr, val) => 
+  100 * arr.reduce((acc,v) => acc + (v < val ? 1 : 0) + (v === val ? 0.5 : 0), 0) / arr.length;
 // percentile([1,2,3,4,5,6,7,8,9,10], 6) -> 55
  ```

From b9edc9a85296bfdf644099bb3f4d3dafbd5fe3fc Mon Sep 17 00:00:00 2001
From: atomiks <sprytex@gmail.com>
Date: Wed, 13 Dec 2017 22:23:43 +1100
Subject: [PATCH 4/4] Update percentile.md

---
 snippets/percentile.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/snippets/percentile.md b/snippets/percentile.md
index 271a90599..eb72b711c 100644
--- a/snippets/percentile.md
+++ b/snippets/percentile.md
@@ -1,6 +1,6 @@
 ### Percentile
 
-Use `Array.filter()` to calculate how many numbers are below the value and how many are the same value and
+Use `Array.reduce()` to calculate how many numbers are below the value and how many are the same value and
 apply the percentile formula.
 
 ```js