I have three columns: Cost, Quantity, and Total, as shown below, and I would like to boxplot the log values of the columns.
I have used the below command but am not sure whether I'm doing it correctly or not.
boxplot (log (df [, c('Cost', 'Quantity', 'Total')]))
Cost
0.84
1.23
1.23
-7.21
0.5
1.23
131
-1095.5
1.23
Quantity
1
1
1
1
1
1
1
1
1
Total
0.84
1.23
1.23
-7.21
0.5
1.23
131
-1095.5
1.23
Thanks
Related
I am able to plot a trisurf chart, but surf does not work.
What am I doing wrong?
pkg load statistics;
figure (1,'name','Matrix Map');
colormap('hot');
t = dlmread('C:\Map3D.csv');
tx =t(:,1);ty=t(:,2);tz=t(:,3);
tri = delaunay(tx,ty);
handle = surf(tx,ty,tz); #This does NOT work
#handle = trisurf(tri,tx,ty,tz); #This does work
`error: surface: rows (Z) must be the same as length (Y) and columns (Z) must be the same as length
(X)
My data is in a CSV (commas not shown here)
1 2 -0.32
2 2 0.33
3 2 0.39
4 2 0.09
5 2 0.14
1 2.5 -0.19
2 2.5 0.13
3 2.5 0.15
4 2.5 0.24
5 2.5 0.33
1 3 0.06
2 3 0.44
3 3 0.36
4 3 0.45
5 3 0.51
1 3.5 0.72
2 3.5 0.79
3 3.5 0.98
4 3.5 0.47
5 3.5 0.55
1 4 0.61
2 4 0.13
3 4 0.44
4 4 0.47
5 4 0.58
1 4.5 0.85
surf error message is different in Matlab or in Octave.
Error message from Matlab:
Z must be a matrix, not a scalar or vector.
The problem is pretty clear here since you specified Z (for you tz) as a vector.
Error message from Octave:
surface: rows (Z) must be the same as length (Y) and columns (Z) must be the same as length (X)
You are wrong here since on your example, columns (Z) = 1, but length (X) = 26, so here is the mistake.
One of the consequences of that is that with surf you cannot have "holes" or undefined points on your grid. On your case you have a X-grid from 1 to 5 and a Y-grid from 2 to 4.5 but point of coordinate (2, 4.5) is not defined.
#Luis Mendo, Matlab and Octave do allow the prototype surf(matrix_x, matrix_y, matrix_z) but the third argument matrix_z still have to be a matrix (not a scalar or vector). Apparently, a matrix of only one line or column is not considered as a matrix.
To solve the issue, I suggest something like:
tx = 1:5; % tx is a vector of length 5
ty = 2:0.5:4.5; % ty is a vector of length 6
tz = [-0.32 0.33 0.39 0.09 0.14;
-0.19 0.13 0.15 0.24 0.33;
0.06 0.44 0.36 0.45 0.51;
0.72 0.79 0.98 0.47 0.55;
0.61 0.13 0.44 0.47 0.58;
0.85 0. 0. 0. 0.]; % tz is a matrix of size 6*5
surf(tx,ty,tz);
Note that I had to invent some values at the points where your grid was not defined, I put 0. but you can change it with the value you prefer.
I have a 10 dimensional matrix with many, many columns (in the hundreds of thousands). I have however, implemented a tag based on the day of an experiment and a condition
So my original matrix looks something like
0.1 0.25 0.64 0.15 0.1 0.96 0.01 0.05....
.
.
.
.
0.2 0.3 0.049 0 0.3 0.71 0.4 0.45....
I was able to implement a tag for the day and experiment type so my matrix looks like
0.1 0.25 0.64 0.15 0.1 0.96 0.01 0.05....
.
.
.
.
0.2 0.3 0.049 0 0.3 0.71 0.4 0.45....
1 1 1 1 2 2 2 2
1 1 2 2 2 3 3 3
The top row represents a day, and the bottom row represents a condition. Is there anyway to "filter" this matrix, call it A, by day and condition in MATLAB? So for example, if I want the day 1 condition 2 "mini-matrix", I can get
0.64 0.15
.
.
.
0.049 0
Yes, you can do this by accessing only the columns matching a certain value in your day or condition rows.
For example, say your input matrix is A, and that the entries in the third row A(3,:) are the days, and the entries in the fourth row A(4,:) are the conditions.
Then A(:, A(3,:) == 2) will give you the subset of columns in A where the day is 2.
And A(:, A(3,:) == 2 & A(4,:) == 1) will give you the columns where the day is 2 and the condition is 1.
The data I am using is available per 3 hour time step. The Julian date for the data is therefore in an increasing order of 3/24 = 0.125 for each row of data value. I am interested only on the daily time step data and I would like to get help how to read only the daily Julian values that are recorded after every 8 Excel rows using Matlab.
Example of my data:
0.125
0.25
0.375
0.5
0.625
0.75
0.875
1
1.125
1.25
1.375
1.5
1.625
1.75
1.875
2
2.125
2.25
2.375
2.5
2.625
2.75
2.875
3
3.125
3.25
3.375
3.5
3.625
3.75
3.875
4
.
.
[continues until 360 and starts back from 0.125]
I have a matrix which is 36 x 2, but I want to seperate the elements to give me 18, 2 x 2 matrices from top to bottom. E.g. if I have a matrix:
1 2
3 4
5 6
7 8
9 10
11 12
13 14
... ...
I want to split it into seperate matrices:
M1 = 1 2
3 4
M2 = 5 6
7 8
M3 = 9 10
11 12
..etc.
maybe the following sample code could useful:
a=rand(36,2);
b=reshape(a,2,2,18)
then with the 3rd index of b you can access your 18 2x2 matrices, eg. b(:,:,2) gives the second 2x2 matrix.
I think that the direct answer to your question is:
sampledata = [...
0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15 0.16 0.17 0.18 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18; ...
0.19 0.20 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.30 0.31 0.32 0.33 0.34 0.35 0.36 1.19 1.20 1.21 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29 1.30 1.31 1.32 1.33 1.34 1.35 1.36];
for ix = 1:(size(sampledata,2)/2)
assignin('base',['M' sprintf('%02d',ix)], sampledata(:,ix*2+[-1 0]))
end
This creates 18 variables, named 'M01' through 'M18', with pieces of the sampledata matrix.
However, please don't use dynamic variable names like this. It will complicate every other piece of code that it touches. Use a cell array, a 3D array (as suggested by #Johannes_Endres +1 BTW), or structure. Anything that removes the need for you to write something like this later on:
%PLEASE DO NOT USE THIS
%ALSO DO NOT BACK YOURSELF INTO A CORNER WHERE YOU HAVE TO DO IT IN THE FUTURE
varNames = who('M*');
for ix = 1:length(varNames )
str = ['result(' num2str(ix) ') = some_function(' varNames {ix} ');'];
eval(str);
end
I've seen code like this, and it is slow and extremely cumbersome to maintain, not to mention the headache and pain to your internal beauty-meter.
x = reshape(1:36*2,[2 36])'
k = 1
for i = 1:2:35
eval(sprintf('M%d = x(%d:%d,:);',k,i,i+1));
k = k+1;
end
I need to sort out few small matrices from 1 huge raw matrix ...according to sorting 1st column (1st column contain either 1, 2, or 3)...
if 1st column is 1, then randomly 75% of the 1 save in file A1, 25% of the 1 save in file A2.
if 1st column is 2, then randomly 75% of the 2 save in file B1, 25% of the 2 save in file B2.
if 1st column is 3, then randomly 75% of the 3 save in file C1, 25% of the 3 save in file C2.
how am i going to write the code?
Example:
a raw matrix has 15 rows x 6 columns:
7 rows are 1 in 1st column, 5 rows are 2 in 1st column, and 3 rows are 3 in 1st column.
1 -0.05 -0.01 0.03 0.07 0.11
1 -0.4 -0.36 -0.32 -0.28 -0.24
1 0.3 0.34 0.38 0.42 0.46
1 0.75 0.79 0.83 0.87 0.91
1 0.45 0.49 0.53 0.57 0.61
1 0.8 0.84 0.88 0.92 0.96
1 0.05 0.09 0.13 0.17 0.21
2 0.5 0.54 0.58 0.62 0.66
2 0.4 0.44 0.48 0.52 0.56
2 0.9 0.94 0.98 1.02 1.06
2 0.85 0.89 0.93 0.97 1.01
2 0.75 0.79 0.83 0.87 0.91
3 0.36 0.4 0.44 0.48 0.52
3 0.6 0.64 0.68 0.72 0.76
3 0.4 0.44 0.48 0.52 0.56
7 rows got 1 in 1st column, randomly take out 75% of 7 rows (which is 7*0.75=5.25) to be new matrix (5rows x 6 columns), the rest of 25% become another new matrix
5 rows got 2 in 1st column, randomly take out 75% of 5 rows (which is 5*0.75=3.75) to be new matrix (4rows x 6 columns), the rest of 25% become another new matrix
3 rows got 3 in 1st column, randomly take out 75% of 3 rows (which is 3*0.75=2.25) to be new matrix (2rows x 6 columns), the rest of 25% become another new matrix
Result:
A1=
1 -0.4 -0.36 -0.32 -0.28 -0.24
1 0.3 0.34 0.38 0.42 0.46
1 0.75 0.79 0.83 0.87 0.91
1 0.8 0.84 0.88 0.92 0.96
1 -0.05 -0.01 0.03 0.07 0.11
B1=
2 0.9 0.94 0.98 1.02 1.06
2 0.85 0.89 0.93 0.97 1.01
2 0.5 0.54 0.58 0.62 0.66
2 0.75 0.79 0.83 0.87 0.91
C1=
3 0.36 0.4 0.44 0.48 0.52
3 0.4 0.44 0.48 0.52 0.56
here is one possible solution to your problem using the function randperm:
% Create matrices
firstcol=ones(15,1);
firstcol(8:12)=2;
firstcol(13:15)=3;
mat=[firstcol rand(15,5)];
% Sort according to first column
A=mat(mat(:,1)==1,:);
B=mat(mat(:,1)==2,:);
C=mat(mat(:,1)==3,:);
% Randomly rearrange lines
A=A(randperm(size(A,1)),:);
B=B(randperm(size(B,1)),:);
C=C(randperm(size(C,1)),:);
% Select first 75% lines (rounding)
A1=A(1:round(0.75*size(A,1)),:);
A2=A(round(0.75*size(A,1))+1:end,:);
B1=B(1:round(0.75*size(B,1)),:);
B1=B(round(0.75*size(B,1))+1:end,:);
C1=C(1:round(0.75*size(C,1)),:);
C1=C(round(0.75*size(C,1))+1:end,:);
Hope it helps.