Questions by xspencer - Page 8
Read this excerpt from Through the Looking-Glass by Lewis Carroll.She was rambling on in this way when she reached the wood: it looked very cool and shady. Well, at any rate it's a great comfort, she said as she stepped under the trees, after being so hot, to get into theinto WHAT? she went on, rather surprised at not being able to think of the word. I mean to get under theunder theunder THIS, you know! putting her hand on the trunk of the tree. What DOES it call itself, I wonder? I do believe it's got no namewhy, to be sure it hasn't!She stood silent for a minute, thinking: then she suddenly began again. Then it really HAS happened, after all! And now, who am I? I WILL remember, if I can! I'm determined to do it! But being determined didn't help much, and all she could say, after a great deal of puzzling, was, L, I KNOW it begins with L!Which question might a reader ask to gain a better understanding of this excerpt?i need asap please answer correctly
Purpose: To practice recursion (and strings) Degree of Difficulty: Easy to Moderate. A palindrome is a string whose characters are the same forward and backwards, for example: "radar", "mom" and "abcddcba". Null (empty) strings and strings with 1 character are considered palindromes. Write a function, is_pal(), that has one parameter - s (a string), and that returns the Boolean value True or False depending on whether s is a palindrome. The function must use recursion. We will need more than 1 base case. When defining the base cases think about the case(s) where we can definitely state that a string is a Palindrome and/or the case(s) where we can definitely state that a string is NOT a Palindrome. Testing Your "main" program will test your function with the following strings: null string, "Z", "yy", "zyz", "Amore, Roma", "Amore, Rome", "xyaz", and "A man, a plan, a canal - Panama.". The test words must be stored in a list. Your program will use a loop to go through this list, calling is_pal() to determine whether each word is or is not a palindrome. The output, for the test words "Z" and "Amore, Rome" would look like this. Notes: Z is a palindrome: True Amore, Rome is a palindrome: False Punctuation and spaces are ignored when considering whether a string is a palindrome. Therefore - before calling is_pal() with a test word, your main program must remove all punctuation and spaces from a test word before using it as an argument. Upper and lower case letters are considered identical when considering whether a string is a palindrome. Therefore - before calling is_pal() with a test word, your main program must "convert" the test word into either all upper-case or all lower-case before using it as an argument.
2. Consider the function f(x) = x - x - 2. (a) [5 marks] Show that it has a root in [1,2]. (b) [7 marks] Use the bisection algorithm to find the approximation of the root after two steps. (c) [8 marks] The following Matlab function implements the bisection method. Complete the function file by filling in the underlined blanks. function [root, fx, ea, iter] =bisect (func, xl, xu, es,maxit) % bisect: root location zeroes % [root, fx, ea, iter] =bisect(func, xl, xu, es, maxit, p1, p2, ...): % uses bisection method to find the root of func % input: % func = name of function % x1, xu lower and upper guesses % es desired relative error % maxit maximum allowable iterations % p1, p2,... = additional parameters used by func % output: % root real root. % fx = function value at root % ea approximate relative error (%) % iter = number of iterations iter = 0; xr = xl; ea = 100; while (1) xrold = xr; xr = (_ _); %the interval is always divided in half iter iter + 1; if xr "=0, ea = abs( 100; end % the approx. relative error is % (current approx. - previous approx.)/current approx. test = func(x1) *func (xr); if test < 0 xu = xr; elseif test > 0 x1 = xr; else ea = 0;end if ea = (_ _ _ _ _), break, end end root = xr; fx = func(xr); Use the Newton-Raphson algorithm to find the approximation of the root after two steps using zo = 1.5.