Professional Interests: Neuroscience

Solved

Making change

Given an amount of currency, return a vector of this form: [100 50 20 10 5 2 1 0.5 0.25 0.1 0.05 0.01] Example: Input a = ...

1 year ago

Question

find(condition,1) is slower than using a loop--any way to speed up?

In general, using a logical condition in conjunction with |find| is slower than using a tight loop: loc = find(X>a, 1) i...

2 years ago | 0 answers | 0

Solved

Balanced number

Given a positive integer find whether it is a balanced number. For a balanced number the sum of first half of digits is equal to...

2 years ago

Solved

Replace NaNs with the number that appears to its left in the row.

Replace NaNs with the number that appears to its left in the row. If there are more than one consecutive NaNs, they should all ...

2 years ago

Solved

Which doors are open?

There are n doors in an alley. Initially they are all shut. You have been tasked to go down the alley n times, and open/shut the...

2 years ago

Solved

Counting Money

Add the numbers given in the cell array of strings. The strings represent amounts of money using this notation: $99,999.99. E...

2 years ago

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...

2 years ago

Solved

Pangrams!

A pangram, or holoalphabetic sentence, is a sentence using every letter of the alphabet at least once. Example: Input s ...

2 years 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, ....

2 years ago

Solved

Pizza!

Given a circular pizza with radius _z_ and thickness _a_, return the pizza's volume. [ _z_ is first input argument.] Non-scor...

2 years 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...

2 years 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...

2 years ago

Solved

Pascal's Triangle

Given an integer n >= 0, generate the length n+1 row vector representing the n-th row of <http://en.wikipedia.org/wiki/Pascals_t...

2 years 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 ...

2 years 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...

2 years 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...

2 years 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...

2 years 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 ...

2 years 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...

2 years 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...

2 years 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...

2 years 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...

2 years 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 + ...

2 years 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...

2 years 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...

2 years 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...

2 years 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...

2 years 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...

2 years 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...

2 years ago