mohanrajendran

# This script is designed to work with ubuntu 16.04 LTS

# ensure system is updated and has basic build tools
sudo apt-get update
sudo apt-get --assume-yes upgrade
sudo apt-get --assume-yes install tmux build-essential gcc g++ make binutils git
sudo apt-get --assume-yes install software-properties-common

# download and install GPU drivers
wget "http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1604/x86_64/cuda-repo-ubuntu1604_8.0.44-1_amd64.deb" -O "cuda-repo-ubuntu1604_8.0.44-1_amd64.deb"

mohanrajendran

#lang planet neil/sicp

(define (append x y)
  (if (null? x)
      y
      (cons (car x) (append (cdr x) y))))

(define (last-pair x)
  (if (null? (cdr x))
      x

mohanrajendran

import pygraphviz as pgv
import networkx as nx

nodeCount = 1
G = nx.DiGraph()
Ranks = {}

def countChange(amount):
    global G
    global Ranks

mohanrajendran

;; Rows and columns start with index 1
(define (pascal row col)
(cond ((or (= col 1) (= col row)) 1)
      (else (+ (pascal (- row 1) col) (pascal (- row 1) (- col 1))))))

;; Test cases
(pascal 1 1)
; 1
(pascal 13 7)
; 924

mohanrajendran

;;; Original function
(define (f n)
(cond ((< n 3) n)
      (else (+ (f (- n 1)) (* 2 (f (- n 2))) (* 3 (f (- n 3)))))))
; f

(f 0)
; 0
(f 1)
; 1

mohanrajendran

The following are the results from defining and evaluating the Ackermann's function on various arguments.

(define (A x y)
  (cond ((= y 0) 0)
  	((= x 0) (* 2 y))
	((= y 1) 2)
	(else (A (- x 1)
	      	 (A x (- y 1))))))
; A

mohanrajendran

Expansion of (+ 4 5) using first definition

(define (+ a b)
  (if (= a 0)
      b
      (inc (+ (dec a) b))))

(+ 4 5)
(inc (+ (dec 4) 5))

mohanrajendran

(define (cbrt-iter guess prev-guess x)
  (if (good-enough? guess prev-guess)
      guess
      (sqrt-iter (improve guess x) 
      		 guess
                 x)))
; cbrt-iter

(define (improve guess x)
  (/ (+ (/ x (square guess)) (* 2 guess)) 3))

mohanrajendran

The good-enough? function is not so effective when we use small numbers as arguments in the function.

For example, when we want to find the square root of 0.0001 which is 0.01,

(sqrt 0.0001)

;.03230844833048122

mohanrajendran

(define (new-if predicate then-clause else-clause)
  (cond (predicate then-clause)
        (else else-clause)))

(define (sqrt-iter guess x)
  (new-if (good-enough? guess x)
          guess
          (sqrt-iter (improve guess x)
 x)))