From 030cf1ed5e82e376baab96ca8d5580ede699c40d Mon Sep 17 00:00:00 2001
From: Saurabh Kumar <developer.saurabh@outlook.com>
Date: Fri, 8 Mar 2024 22:40:27 +0530
Subject: [PATCH] Document built-in functions

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+# Built-in Functions
+
+LPython has a variety of functions and types built into it that are always available.
+
+### abs(x)
+
+- **Parameter**
+    - x : integer (i8, i16, i32, i64), floating point number (f32, f64), complex number (c32, c64) or bool
+- **Returns** : integer (i8, i16, i32, i64), floating point number (f32, f64)
+
+Returns the absolute value of a number. If the argument is a complex number, its magnitude is returned.
+
+
+### bin(n)
+
+- **Parameters**
+    - n : integer (i32)
+- **Returns** : str
+
+Returns the binary representation of n as a '0b' prefixed string.
+
+
+### complex(x=0, y=0)
+
+- **Parameters**
+    - x : integer (i32, i64) or floating point number (f32, f64)
+    - y : integer (i32, i64) or floating point number (f32, f64)
+- **Returns** : complex number (c32, c64)
+
+Returns a complex number with the provided real and imaginary parts. Both x and y should be of the same type. However, using both the 32-bit and 64-bit versions of the same type together is allowed. In that case, the returned complex number is of 64-bit type.
+
+Example:
+
+```python
+real: i32 = 10
+imag: i64 = 22
+c: c64 = complex(real, imag)
+```
+
+### divmod(x, y)
+
+- **Parameters**
+    - x : integer (i32)
+    - y : integer (i32)
+- **Returns** : tuple[i32, i32]
+
+Returns the tuple (x // y, x % y).
+
+
+### exp(x)
+
+- ****Parameter****
+    - x : floating point number (f32, f64)
+- **Returns** : floating point number (f32, f64) between [0.0, inf]
+
+Returns the base-e exponential of x (e<sup>x</sup>), where e is the Euler's number (2.71828). For a very large output, the function returns **inf** indicating overflow.
+
+
+### hex(n)
+
+- **Parameters**
+    - n : integer (i32)
+- **Returns** : str
+
+Returns the hexadecimal representation of n as a '0x' prefixed string.
+
+
+### len(s)
+
+- **Parameters**
+    - s : sequence (such as string, tuple, list or range) or collection (such as a dictionary or set)
+- **Returns** : integer (i32)
+
+Returns the number of items present in an object.
+
+
+### max(x, y)
+
+- **Parameters**
+    - x : integer (i32) or floating point number (f64)
+    - y : integer (i32) or floating point number (f64)
+- **Returns** : integer (i32) or floating point number (f64)
+
+Returns the greater value between x and y. Both x and y should be of the same type.
+
+
+### min(x, y)
+
+- **Parameters**
+    - x : integer (i32) or floating point number (f64)
+    - y : integer (i32) or floating point number (f64)
+- **Returns** : integer (i32) or floating point number (f64)
+
+Returns the smaller value between x and y. Both x and y should be of the same type.
+
+
+### mod(x, y)
+
+- **Parameters**
+    - x : integer (i32, i64) or floating point number (f32, f64)
+    - y : integer (i32, i64) or floating point number (f32, f64)
+- **Returns** : integer (i32, i64) or floating point number (f32, f64)
+
+Returns the remainder of x / y, or x when x is smaller than y. Both x and y should be of the same type.
+
+
+### pow(x, y)
+
+- **Parameters**
+    - x : integer (i32, i64), floating point number (f32, f64), complex number (c32) or bool
+    - y: integer (i32, i64), floating point number (f32, f64) or bool
+- **Returns** : integer (i32), floating point number (f32, f64) or a complex number
+
+Returns x<sup>y</sup>. When x is of type bool, y must also be of the same type. If x is 32-bit complex number (c32), y can only be a 32-bit integer (i32).
+
+**Note** : `x ** y` is the recommended method for doing the above calculation.
+
+
+### round(x)
+
+- **Parameters**
+    - x : integer (i8, i16, i32, i64), floating point number (f32, f64) or bool
+- **Returns** : integer (i8, i16, i32, i64)
+
+Returns the integer nearest to x.
+
+
+### sum(arr)
+
+- **Parameters**
+    - arr : list of integers (list[i32], list[i64]) or floating point numbers (list[i32], list[f64])
+- **Returns** : integer (i32, i64) or floating point number (f32, f64)
+
+Returns the sum of all elements present in the list.
+
+
+### oct(n)
+
+- **Parameters**
+    - n : integer (i32)
+- **Returns** : str
+
+Returns the octal representation of n as a '0o' prefixed string.
+
+
+
+