Problem

Find the elements of a matrix according to a defined property.
From A = [5,2,3] and B = [1,2,3,4,5,6,7,8,9,10] produce a vector C where : C(1) is the sum of the first A(1) elements of B, ...

13 years ago | 3 | 91 solvers

Solved

Find the elements of a matrix according to a defined property.
From A = [5,2,3] and B = [1,2,3,4,5,6,7,8,9,10] produce a vector C where : C(1) is the sum of the first A(1) elements of B, ...

13 years ago

Problem

Matrix which contains the values of an other matrix A at the given locations.
If you have two matrices, which together give xc and yc coordinates into another matrix, eg : xc = [1 1 1; 2 2 1]; ...

13 years ago | 1 | 239 solvers

Solved

Matrix which contains the values of an other matrix A at the given locations.
If you have two matrices, which together give xc and yc coordinates into another matrix, eg : xc = [1 1 1; 2 2 1]; ...

13 years ago

Problem

Create a matrix X, where each column is a shifted copy of the vector v
Example : in->v = (1:5)'; 1 2 3 4 5 out-> [1 5 4 3 2;2 1 5 4 3;3 2 1 5 4;4 3 2 1 5;5 4 3 ...

13 years ago | 1 | 221 solvers

Solved

Create a matrix X, where each column is a shifted copy of the vector v
Example : in->v = (1:5)'; 1 2 3 4 5 out-> [1 5 4 3 2;2 1 5 4 3;3 2 1 5 4;4 3 2 1 5;5 4 3 ...

13 years ago

Problem

Duplicate each element of a vector.
for an n-dimensional vector x, the function should return another vector 2n-dimension which each element is repeated twice. Ex...

13 years ago | 1 | 633 solvers

Solved

Duplicate each element of a vector.
for an n-dimensional vector x, the function should return another vector 2n-dimension which each element is repeated twice. Ex...

13 years ago

Problem

First non-zero element in each column
For a given matrix, calculate the index of the first non-zero element in each column. Assuming a column with all elements zero ...

14 years ago | 7 | 931 solvers

Solved

Duplicates
Write a function that accepts a cell array of strings and returns another cell array of strings *with only the duplicates* retai...

14 years ago

Solved

Maximum running product for a string of numbers
Given a string s representing a list of numbers, find the five consecutive numbers that multiply to form the largest number. Spe...

14 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 ...

14 years ago

Solved

First N Perfect Squares
*Description* Return the first N perfect squares *Example* input = 4; output = [ 1 4 9 16 ];

14 years ago

Solved

Number of 1s in the Binary Representation of a Number
*Description* Return the number of 1s in the (unsigned integer) binary representation of a number. This function should be ab...

14 years 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...

14 years ago

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...

14 years ago

Solved

Summing Digits within Text
Given a string with text and digits, add all the numbers together. Examples: Input str = '4 and 20 blackbirds baked in a...

14 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...

14 years 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...

14 years ago

Solved

given 3 sides, find area of this triangle
1:3 -> 0; 3:5 -> 6

14 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, ....

14 years 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...

14 years ago

Problem

Matrix with different incremental runs
Given a vector of positive integers a (>=0); How does one create the matrix where the ith column contains the vector 1:a(i) poss...

14 years ago | 1 | 130 solvers

Solved

Matrix with different incremental runs
Given a vector of positive integers a (>=0); How does one create the matrix where the ith column contains the vector 1:a(i) poss...

14 years ago

Solved

First non-zero element in each column
For a given matrix, calculate the index of the first non-zero element in each column. Assuming a column with all elements zero ...

14 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...

14 years 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. Example...

14 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 + ...

14 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...

14 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...

14 years ago