diff --git a/array.libsonnet b/array.libsonnet
index f000c87..8411210 100644
--- a/array.libsonnet
+++ b/array.libsonnet
@@ -34,4 +34,22 @@ local d = import 'doc-util/main.libsonnet';
         else std.length(indexable),
     };
     indexable[invar.index:invar.end:step],
+
+  '#filterMapWithIndex':: d.fn(
+    |||
+      `filterMapWithIndex` works the same as `std.filterMap` with the addition that the index is passed to the functions.
+
+      `filter_func` and `map_func` function signature: `function(index, array_item)`
+    |||,
+    [
+      d.arg('filter_func', d.T.func),
+      d.arg('map_func', d.T.func),
+      d.arg('arr', d.T.array),
+    ],
+  ),
+  filterMapWithIndex(filter_func, map_func, arr): [
+    map_func(i, arr[i])
+    for i in std.range(0, std.length(arr) - 1)
+    if filter_func(i, arr[i])
+  ],
 }
diff --git a/docs/README.md b/docs/README.md
index fbd33a5..61d9c39 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -21,5 +21,6 @@ in the future, but also provides a place for less general, yet useful utilities.
 * [date](date.md)
 * [inspect](inspect.md)
 * [jsonpath](jsonpath.md)
+* [number](number.md)
 * [string](string.md)
 * [url](url.md)
\ No newline at end of file
diff --git a/docs/array.md b/docs/array.md
index f273293..cc538d8 100644
--- a/docs/array.md
+++ b/docs/array.md
@@ -12,10 +12,22 @@ local array = import "github.com/jsonnet-libs/xtd/array.libsonnet"
 
 ## Index
 
+* [`fn filterMapWithIndex(filter_func, map_func, arr)`](#fn-filtermapwithindex)
 * [`fn slice(indexable, index, end='null', step=1)`](#fn-slice)
 
 ## Fields
 
+### fn filterMapWithIndex
+
+```ts
+filterMapWithIndex(filter_func, map_func, arr)
+```
+
+`filterMapWithIndex` works the same as `std.filterMap` with the addition that the index is passed to the functions.
+
+`filter_func` and `map_func` function signature: `function(index, array_item)`
+
+
 ### fn slice
 
 ```ts
diff --git a/docs/number.md b/docs/number.md
new file mode 100644
index 0000000..aa30879
--- /dev/null
+++ b/docs/number.md
@@ -0,0 +1,43 @@
+---
+permalink: /number/
+---
+
+# number
+
+```jsonnet
+local number = import "github.com/jsonnet-libs/xtd/number.libsonnet"
+```
+
+`number` implements helper functions for processing number.
+
+## Index
+
+* [`fn inRange(v, from, to)`](#fn-inrange)
+* [`fn maxInArray(arr, default=0)`](#fn-maxinarray)
+* [`fn minInArray(arr, default=0)`](#fn-mininarray)
+
+## Fields
+
+### fn inRange
+
+```ts
+inRange(v, from, to)
+```
+
+`inRange` returns true if `v` is in the given from/to range.`
+
+### fn maxInArray
+
+```ts
+maxInArray(arr, default=0)
+```
+
+`maxInArray` finds the biggest number in an array
+
+### fn minInArray
+
+```ts
+minInArray(arr, default=0)
+```
+
+`minInArray` finds the smallest number in an array
\ No newline at end of file
diff --git a/main.libsonnet b/main.libsonnet
index 59c4034..74a98ad 100644
--- a/main.libsonnet
+++ b/main.libsonnet
@@ -19,6 +19,7 @@ local d = import 'doc-util/main.libsonnet';
   date: (import './date.libsonnet'),
   inspect: (import './inspect.libsonnet'),
   jsonpath: (import './jsonpath.libsonnet'),
+  number: (import './number.libsonnet'),
   string: (import './string.libsonnet'),
   url: (import './url.libsonnet'),
 }
diff --git a/number.libsonnet b/number.libsonnet
new file mode 100644
index 0000000..f91014a
--- /dev/null
+++ b/number.libsonnet
@@ -0,0 +1,48 @@
+local d = import 'doc-util/main.libsonnet';
+
+{
+  '#': d.pkg(
+    name='number',
+    url='github.com/jsonnet-libs/xtd/number.libsonnet',
+    help='`number` implements helper functions for processing number.',
+  ),
+
+  '#inRange':: d.fn(
+    '`inRange` returns true if `v` is in the given from/to range.`',
+    [
+      d.arg('v', d.T.number),
+      d.arg('from', d.T.number),
+      d.arg('to', d.T.number),
+    ]
+  ),
+  inRange(v, from, to):
+    v > from && v <= to,
+
+  '#maxInArray':: d.fn(
+    '`maxInArray` finds the biggest number in an array',
+    [
+      d.arg('arr', d.T.array),
+      d.arg('default', d.T.number, default=0),
+    ]
+  ),
+  maxInArray(arr, default=0):
+    std.foldl(
+      std.max,
+      std.set(arr),
+      default,
+    ),
+
+  '#minInArray':: d.fn(
+    '`minInArray` finds the smallest number in an array',
+    [
+      d.arg('arr', d.T.array),
+      d.arg('default', d.T.number, default=0),
+    ]
+  ),
+  minInArray(arr, default=0):
+    std.foldl(
+      std.min,
+      std.set(arr),
+      default,
+    ),
+}