Question

Customizing tab completion

I have a function that accepts paired name/value arguments, e.g. solve(A,b,'accuracy',1e-13,'method','LU','threshold',1e-...

9 years ago | 1 answer | 0

Problem

Column norms of a matrix

Given a matrix M, return a vector y such that for each k y(k)=norm(M(:,k)) (y(k) is the Euclidean norm of the k-th col...

9 years ago | 3 | 284 solvers

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...

9 years ago

Solved

The Hitchhiker's Guide to MATLAB

Output logical "true" if the input is the answer to life, the universe and everything. Otherwise, output logical "false".

9 years ago

Solved

Column norms of a matrix

Given a matrix M, return a vector y such that for each k y(k)=norm(M(:,k)) (y(k) is the Euclidean norm of the k-th col...

9 years ago

Answered

return value optimization when overwriting

It seems that you can indeed, see http://blogs.mathworks.com/loren/2007/03/22/in-place-operations-on-data/? I cannot understa...

return value optimization when overwriting

It seems that you can indeed, see http://blogs.mathworks.com/loren/2007/03/22/in-place-operations-on-data/? I cannot understa...

9 years ago | 0

Question

overloading x=[a b; c d]

Suppose a,b,c,d are instances of a custom Matlab class. I can redefine [a b] and [a;b] by overloading horzcat() and vertcat(); h...

9 years ago | 1 answer | 2

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...

9 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...

9 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...

9 years 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...

9 years 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 ...

9 years ago

Solved

Sum all integers from 1 to 2^n

Given the number x, y must be the summation of all integers from 1 to 2^x. For instance if x=2 then y must be 1+2+3+4=10.

9 years ago

Solved

Sorted highest to lowest?

Return 1 if the input is sorted from highest to lowest, 0 if not. Example: 1:7 -> 0 [7 5 2] -> 1

9 years ago

Solved

Determine if input is odd

Given the input n, return true if n is odd or false if n is even.

9 years ago

Solved

Times 2 - START HERE

Try out this test problem first. Given the variable x as your input, multiply it by two and put the result in y. Examples:...

9 years ago

Question

return value optimization when overwriting

Consider the following scenario. function A=frobnicate(A) A(1)=1; end X=zeros(2000,2000); X=frobnicate(X); ...

9 years ago | 2 answers | 0

Question

Detecting "a and b are the same variable" in O(1) via pointers

I know Matlab uses copy-on-write; that is, if I assign |a=b| and then never modify |a| and |b|, they point to the same chunk of ...

9 years ago | 2 answers | 0

Question

GLOBAL could be very inefficient

I am using a GLOBAL statement inside an if command, so that I import the global variable into the local namespace only if it is ...

9 years ago | 1 answer | 0

Question

GLOBAL could be very inefficient

I am using the GLOBAL instruction inside an if statement, to create a global variable only if it is needed. However, the code an...

9 years ago | 0 answers | 0