Community Profile

photo

Rafael Hernandez-Walls


Last seen: 9 dagar ago Active since 2010

Followers: 0   Following: 0

Message

My interest is everything related to numerical schemes applied to PDE and Oceanography, UABC.

Statistics

All
  • MATLAB Mini Hack Participant
  • Treasure Hunt Participant
  • Knowledgeable Level 3
  • 6 Month Streak
  • Quiz Master
  • Community Group Solver
  • Personal Best Downloads Level 1
  • First Submission
  • Knowledgeable Level 2
  • Introduction to MATLAB Master
  • Project Euler I
  • Cody Problems in Japanese Master

View badges

Feeds

Solved


Count consecutive 0's in between values of 1
So you have some vector that contains 1's and 0's, and the goal is to return a vector that gives the number of 0's between each ...

3 månader ago

Solved


Molar Air Density from Temperature and Pressure
The molar density of air can be found from the Temperature and Pressure using the ideal gas law. where the Molar density STP ...

mer än ett år ago

Solved


Calculate Wind Chill Factor
The NWS Wind Chill Temperature (WCT) index formula for calculating the dangers from winter winds and freezing temperatures: Cal...

mer än ett år ago

Solved


Air Mass to Star for an Observer at Mean Sea Level
Air mass is a measure of how much atmosphere light from a source above the atmosphere (eg sun, planet, star) has to travel throu...

mer än ett år ago

Solved


Find Air Temperature from Cricket Stridulation Rate
Stridulation is the process that creates a cricket's “chirp” by rubbing their wings or legs. According to the Old Farmer's Alma...

mer än ett år ago

Solved


Construyendo matrices parte 2
Construye la siguiente matriz a partir de otros tres vectores/matrices. [ 1 8 15 3 3 3 3 2 9 16 3 3...

mer än ett år ago

Solved


Sum of series IV
What is the sum of the following sequence: Σ(-1)^(k+1) (2k-1)^2 for k=1...n for different n?

mer än ett år ago

Solved


Back to basics 22 - Rotate a matrix
Covering some basic topics I haven't seen elsewhere on Cody. Rotate the input matrix 90 degrees counterclockwise (e.g. [1 2; ...

mer än ett år ago

Solved


Composite Trapezoidal Rule for Numeric Integration
Use the trapezoidal rule to numerically integrate a function, _f(x)_, passed as the first argument, between upper and lower limi...

mer än ett år ago

Solved


Differential equations I
Given a function handle |f| an initial condition |y0| and a final time |tf|, solve numerically the differential equation dy...

mer än ett år ago

Solved


Weighted Convolution
Given two input vectors x = [x_1, x_2, ..., x_K] and y = [y_1, y_2, ..., y_K] of equal length, compute the weighted convolution ...

nästan 2 år ago

Answered
Determine if any key is being pressed
If only use the function: pause

mer än 2 år ago | 0

Solved


The Piggy Bank Problem
Given a cylindrical piggy bank with radius g and height y, return the bank's volume. [ g is first input argument.] Bonus though...

mer än 2 år ago

Solved


mathematics , probability problem
How many different result can we have, rolling k dice?

mer än 2 år ago

Solved


MATLAB Basics: Complex Conjugates
For a given complex number, x, return the complex conjugate, y.

mer än 2 år ago

Solved


MATLAB Basics: Complex Numbers
For a given complex number, x, return the real and imaginary parts as a vector, y = [Real Imaginary].

mer än 2 år ago

Solved


Flip coins

mer än 2 år ago

Solved


Normalizing a vector

mer än 2 år ago

Solved


Return fibonacci sequence do not use loop and condition
Calculate the nth Fibonacci number. Given n, return f where f = fib(n) and f(1) = 1, f(2) = 1, f(3) = 2, ... Examples: ...

mer än 2 år ago

Solved


Number of Even Elements in Fibonacci Sequence
Find how many even Fibonacci numbers are available in the first d numbers. Consider the following first 14 numbers 1 1 2...

mer än 2 år ago

Solved


Find the next Fibonacci number
In the sequence of Fibonacci numbers, every number is the sum of the two preceding ones: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55...

mer än 2 år ago

Answered
matlab not plotting graph
You need one point in the equation of z h = [2,4,6,8,10]; x = 10.1; y = 2.5; z = (x * h.^2 - x - sqrt(y^2*h.^2 - y^2))./ (h....

mer än 2 år ago | 0

Solved


Mass Conversion 1

nästan 3 år ago

Answered
how i can find the chessboard lines and draw on the main image with any solution
Maybe you can use the Radon Transform, like this link: https://www.mathworks.com/help/images/detect-lines-using-the-radon-trans...

nästan 3 år ago | 0

Answered
how can I get y which correspond to x and then plot (x,y)??
Try this: x=linspace(-4,4); for r=1:length(x) y(r)=fzero(@(y)y.^3+0.2*exp(-1*x(r).^2)*y.^2-2.2039*y.^2+0.8155,1); end p...

nästan 3 år ago | 0

Answered
How to read data from text file and store as it is with variables
Assuming you have a file with only following line (name of file= 'algo.txt'): phi1_32_1 = 1 You could then read the line with...

nästan 3 år ago | 0

Answered
numerical simulation of travelling wave of epidemic model
try this.... clear all; xl=0; xr=1; %domain[xl,xr] J=1000; % J: number of dividion for x dx=(x...

nästan 3 år ago | 0

Answered
Read a txt file
try this Dens1 = [A(:,1),9.11*A(:,2).^(1.326)]; fileID1=fopen('E1.txt','w'); % [n,~]=size(Dens1); for k=1:n b=fprintf(...

nästan 3 år ago | 0

Answered
How to display correlation coefficents on plot?
you can try something like this: x = [0 0.000009 0.000018 0.000028 0.000037 0.000046 0.000055 0.000065 0.000074 0.000083 0.0000...

nästan 3 år ago | 0

Answered
extracting value from a matrix
I think it is better to put the variable X as a string and from there start. for example: X=['1000000000000000000000000000000...

nästan 3 år ago | 0

| accepted

Load more