Erik Johnson
Followers: 0 Following: 0
Professor & Vice Dean, Viterbi School of Engineering, University of Southern California B.S. (1988), M.S. (1993), Ph.D. (1997), Aeronautical & Astronautical Engineering, University of Illinois at Urbana-Champaign https://cee.usc.edu/directory/faculty/profile/?lname=Johnson&fname=Erik
Statistics
RANK
6 534
of 295 448
REPUTATION
6
CONTRIBUTIONS
2 Questions
1 Answer
ANSWER ACCEPTANCE
0.0%
VOTES RECEIVED
4
RANK
91 of 20 227
REPUTATION
11 024
AVERAGE RATING
4.50
CONTRIBUTIONS
2 Files
DOWNLOADS
98
ALL TIME DOWNLOADS
102311
CONTRIBUTIONS
0 Posts
CONTRIBUTIONS
0 Public Channels
AVERAGE RATING
CONTRIBUTIONS
0 Highlights
AVERAGE NO. OF LIKES
Feeds
Solved
Binary numbers
Given a positive, scalar integer n, create a (2^n)-by-n double-precision matrix containing the binary numbers from 0 through 2^n...
mer än 7 år ago
Solved
Remove the vowels
Remove all the vowels in the given phrase. Example: Input s1 = 'Jack and Jill went up the hill' Output s2 is 'Jck nd Jll wn...
mer än 7 år ago
Solved
Remove all the consonants
Remove all the consonants in the given phrase. Example: Input s1 = 'Jack and Jill went up the hill'; Output s2 is 'a ...
mer än 7 år ago
Solved
Find the longest sequence of 1's in a binary sequence.
Given a string such as s = '011110010000000100010111' find the length of the longest string of consecutive 1's. In this examp...
mer än 7 år ago
Solved
Find the alphabetic word product
If the input string s is a word like 'hello', then the output word product p is a number based on the correspondence a=1, b=2, ....
mer än 7 år ago
Solved
Cell joiner
You are given a cell array of strings and a string delimiter. You need to produce one string which is composed of each string fr...
mer än 7 år ago
Solved
Nearest Numbers
Given a row vector of numbers, find the indices of the two nearest numbers. Examples: [index1 index2] = nearestNumbers([2 5 3...
mer än 7 år ago
Solved
Return the largest number that is adjacent to a zero
This example comes from Steve Eddins' blog: <http://blogs.mathworks.com/steve/2009/05/27/learning-lessons-from-a-one-liner/ Lear...
mer än 7 år ago
Solved
Bullseye Matrix
Given n (always odd), return output a that has concentric rings of the numbers 1 through (n+1)/2 around the center point. Exampl...
mer än 7 år ago
Solved
Target sorting
Sort the given list of numbers |a| according to how far away each element is from the target value |t|. The result should return...
mer än 7 år ago
Solved
The Goldbach Conjecture
The <http://en.wikipedia.org/wiki/Goldbach's_conjecture Goldbach conjecture> asserts that every even integer greater than 2 can ...
mer än 7 år ago
Solved
Which values occur exactly three times?
Return a list of all values (sorted smallest to largest) that appear exactly three times in the input vector x. So if x = [1 2...
mer än 7 år ago
Solved
Sort a list of complex numbers based on far they are from the origin.
Given a list of complex numbers z, return a list zSorted such that the numbers that are farthest from the origin (0+0i) appear f...
mer än 7 år ago
Solved
Summing digits
Given n, find the sum of the digits that make up 2^n. Example: Input n = 7 Output b = 11 since 2^7 = 128, and 1 + ...
mer än 7 år ago
Solved
Who Has the Most Change?
You have a matrix for which each row is a person and the columns represent the number of quarters, nickels, dimes, and pennies t...
mer än 7 år ago
Solved
Return the 3n+1 sequence for n
A Collatz sequence is the sequence where, for a given number n, the next number in the sequence is either n/2 if the number is e...
mer än 7 år ago
Solved
Back and Forth Rows
Given a number n, create an n-by-n matrix in which the integers from 1 to n^2 wind back and forth along the rows as shown in the...
mer än 7 år ago
Solved
Most nonzero elements in row
Given the matrix a, return the index r of the row with the most nonzero elements. Assume there will always be exactly one row th...
mer än 7 år ago
Solved
Find the numeric mean of the prime numbers in a matrix.
There will always be at least one prime in the matrix. Example: Input in = [ 8 3 5 9 ] Output out is 4...
mer än 7 år ago
Solved
Remove any row in which a NaN appears
Given the matrix A, return B in which all the rows that have one or more <http://www.mathworks.com/help/techdoc/ref/nan.html NaN...
mer än 7 år ago
Solved
Finding Perfect Squares
Given a vector of numbers, return true if one of the numbers is a square of one of the other numbers. Otherwise return false. E...
mer än 7 år ago
Solved
Create times-tables
At one time or another, we all had to memorize boring times tables. 5 times 5 is 25. 5 times 6 is 30. 12 times 12 is way more th...
mer än 7 år ago
Solved
Fibonacci sequence
Calculate the nth Fibonacci number. Given n, return f where f = fib(n) and f(1) = 1, f(2) = 1, f(3) = 2, ... Examples: Inpu...
mer än 7 år ago
Solved
Determine whether a vector is monotonically increasing
Return true if the elements of the input vector increase monotonically (i.e. each element is larger than the previous). Return f...
mer än 7 år ago
Solved
Swap the first and last columns
Flip the outermost columns of matrix A, so that the first column becomes the last and the last column becomes the first. All oth...
mer än 7 år ago
Solved
Make a checkerboard matrix
Given an integer n, make an n-by-n matrix made up of alternating ones and zeros as shown below. The a(1,1) should be 1. Examp...
mer än 7 år ago
Solved
Find all elements less than 0 or greater than 10 and replace them with NaN
Given an input vector x, find all elements of x less than 0 or greater than 10 and replace them with NaN. Example: Input ...
mer än 7 år ago
Solved
Triangle Numbers
Triangle numbers are the sums of successive integers. So 6 is a triangle number because 6 = 1 + 2 + 3 which can be displa...
mer än 7 år ago
Solved
Column Removal
Remove the nth column from input matrix A and return the resulting matrix in output B. So if A = [1 2 3; 4 5 6]; and ...
mer än 7 år ago