Stack Overflow
Stack Overflow

Questions tagged [4d]

4D involves calculations in four dimensions and typically relates to graphics programming. Use the [4d-database] tag for questions about the 4th Dimension database.

From Wikipedia, as of 5 March 2017‎:

In mathematics, four-dimensional ("4D") is a geometric space with four dimensions. It is typically meant to mean four-dimensional Euclidean space, generalizing the rules of three-dimensional Euclidean space. It has been studied by mathematicians and philosophers or over two centuries, both for its own interest and for the insights it offered mathematicians and related fields.

146 questions
0
votes
1 answer

Numpy convert list of 3D variable size volumes to 4D array

I'm working on a neural network where I am augmenting data via rotation and varying the size of each input volume. Let me back up, the input to the network is a 3D volume. I generate variable size 3D volumes, and then pad each volume with zero's…
Kendall Weihe
  • 2,021
  • 4
  • 27
  • 53
0
votes
1 answer

4-d double array can't be saved into .mat matlab

I have 4-D double array named pic, with dim of ( 512, 512, 100, 29). actually they are '.nii' images with dim of ( 512,512,100) . each .nii image has 100 slice. I loaded 29 nii image in matlab in pic(:,:,:,i) array and now I want to save it. but…
patra
  • 9
  • 4
0
votes
1 answer

matlab 4D interpolation plot

Here is a sample dataset. x = linspace(10,20,50); y = linspace(10,20,50); z = cos(linspace(0,2*pi,50)); time = linspace(1,60,50); sci_temp = randi(100,50,1); x,y,z is position, and sci_temp is temperature data. I wonder how to draw trajectory over…
Cho
  • 163
  • 3
  • 13
0
votes
1 answer

Create an array showing the probability based on two separate matrices showing probability of outcomes in two periods

I have two matrices in R showing the probability of each scoreline in the first half, and second half of a soccer game. I want to combine these to have one object (I'm guessing a 4 dimensional array) giving me the probability of each HT/FT scoreline…
user1165199
  • 6,351
  • 13
  • 44
  • 60
0
votes
0 answers

How to plot three coordinates in function of a fourth (3 positional coordinates in function of time) in R?

I would like to plot a 4 dimensional graph in R. I have three coordinates of position and a fourth variable (time). In this plot I would like to show these 3 coordinates in function of time. I only have one observation for each coordinate in each…
Pablo Fonseca
  • 1
  • 1
0
votes
1 answer

Error in Matlab immovie

I keep getting errors when trying to make an animation from a 4D matrix. Here is the code: >> %movie...fail c = zeros([size(u_filt1), 339]); %input number of frames for ii=1:size(c,3) c(:,:,ii)=eval(['u_filt', num2str(ii)]); end…
Laura Szczyrba
  • 1
0
votes
1 answer

4D interpolation plot with matlab of scattered data

I have a set of data with a value at some x,y,z coordinates. However, the coordinates are not evenly spaced. I would like to interpolate the data and have a 3D interpolated plot where the color is the interpolated value at each x,y,z coordinates…
sponce
  • 1,279
  • 2
  • 11
  • 17
0
votes
0 answers

3D parametric plot with three parameters using any language or software

I'm looking for a possibility to plot 3D objects using vectors with three parameters using any language or software (I prefer Mathematica but obviously it's very complicated there). They are of the form {x,y,z} = {f[u,v,w], g[u,v,w], h[u,v,w]} and…
Fid Rewe
  • 101
  • 2
0
votes
1 answer

Use R to draw a 4d figure

I have some data in CSV file and want to draw a 4d graphic. The x, y, z axis is respectively one column in the file. and the 4th dimension is a color respective of the value of another column in the file. How can I get a plot with both the x,y,z and…
Alisa Zhang
  • 3
  • 2
0
votes
0 answers

matplotlib 3D bog

I draw 4D plot. My plot has some parts ( surfaces ). I generate each part ( each surface ) in a different array. The last part ( the last surface ) of graph has two sections. 1 in upside and second in back. But in graph in pylab this isn't…
mohsen ramezani
  • 11
  • 2
0
votes
1 answer

Averaging subsets of certain dimensions in a 4D matrix in MATLAB

My problem stems from having difficulty conceptualizing 4D matrices (as opposed to 3D). In MATLAB, I have data stored in a 5x5x7x54 matrix. The 5x5 part is symmetric across the diagonal and represents correlations in activity between 5 brain areas.…
chainhomelow
  • 347
  • 1
  • 12
0
votes
1 answer

Do you always have to start at the index zero when writing a 2D list?

I want to fill in a 2Dlist, but start at the third position [2]. Is this somehow possible? A short code for understanding what i mean: List> List2D = new List>(); for (int i = 0; i < 5; i++) { List2D[2].Add("i") } I get…
wouter
  • 359
  • 4
  • 15
0
votes
2 answers

Adding a 4th variable to a 3D plot in Python

I have 3 different parameters X,Y and Z over a range of values, and for each combination of these a certain value of V. To make it clearer, the data would look something like this. X Y Z V 1 1 2 10 1 2 3 15 etc... I'd like to visualize…
muffinman
  • 1
  • 1
  • 2
0
votes
1 answer

Access violation reading location in 4D dynamic array

I am getting an "Access violation reading location" error in my program when trying to access elements in my 4D dynamic array. Here is my allocation code void mazeGen(int**** mazes, int width, int height,stack backtracker) { …
JustinWeq
  • 158
  • 11
0
votes
0 answers

Rotate in 4 dimensions javascript

The equation for 3D rotation on z is: d = degrees newx = x*cos(d) - y*sin(d) newy = y*cos(d) + x*sin(d) So basically you replace x and y with the two axis that are not the rotational axis, but how would you do this with x, y, z, and w?
user3786755
1 2 3
…
9
10