I have a excell file that I need to read into matlab. I already read excel file as cell form in matlab.
I want to convert cell data type to structure in matlab. My excel file is like this
Va Ia Vb Ib Vc ... ...
01:00 100 10 200 20 300 ... ...
02:00 110 11 210 21 310 ... ...
03:00 120 12 220 22 320 ... ...
04:00 130 13 230 23 330 ... ...
... ... ... ... ... ... ... ...
and then I know taht structure data type consist field and material. I wanna that first column use to field name. for instance, I want this
structure A
field 1: Va
material : [100;110;120;130 ... ...]
field 2: Ia
material : [10 ;11 ;12 ;13 ... ...]
and I will use that to access variables in structure
A.Va(3)= ~~~~~ ;somethig.....
Related
I have a function that takes as input some of the values in a table and returns a tuple if you will - three separate return values, which I want to transpose into the output of a query. Here's a simplified example of what I want to achieve:
multiplier:{(x*2;x*3;x*3)};
select twoX:multiplier[price][0]; threeX:multiplier[price][1]; fourX:multiplier[price][2] from data;
The above basically works (I think I've got the syntax right for the simplified example - if not then hopefully my intention is clear), but is inefficient because I'm calling the function three times and throwing away most of the output each time. I want to rewrite the query to only call the function once, and I'm struggling.
Update
I think I missed a crucial piece of information in my explanation of the problem which affects the outcome - I need to get other data in the query alongside the output of my function. Here's a hopefully more realistic example:
multiplier:{(x*2;x*3;x*4)};
select average:avg price, total:sum price, twoX:multiplier[sum price][0]; threeX:multiplier[sum price][1]; fourX:multiplier[sum price][2] by category from data;
I'll have a go at adapting your answers to fit this requirement anyway, and apologies for missing this bit of information. The real function if a proprietary and fairly complex algorithm and the real query has about 30 output columns, hence the attempt at simplifying the example :)
If you're just looking for the results themselves you can extract (exec) as lists, create dictionary and then flip the dictionary into a table:
q)exec flip`twoX`threeX`fourX!multiplier[price] from ([]price:til 10)
twoX threeX fourX
-----------------
0 0 0
2 3 4
4 6 8
6 9 12
8 12 16
10 15 20
12 18 24
14 21 28
16 24 32
18 27 36
If you need other columns from the original table too then its trickier but you could join the tables sideways using ,'
q)t:([]price:til 10)
q)t,'exec flip`twoX`threeX`fourX!multiplier[price] from t
An apply # can also achieve what you want. Here data is just a table with 10 random prices. # is then used to apply the multiplier function to the price column while also assigning a column name to each of the three resulting lists:
q)data:([] price:10?100)
q)multiplier:{(x*2;x*3;x*3)}
q)#[data;`twoX`threeX`fourX;:;multiplier data`price]
price twoX threeX fourX
-----------------------
80 160 240 240
24 48 72 72
41 82 123 123
0 0 0 0
81 162 243 243
10 20 30 30
36 72 108 108
36 72 108 108
16 32 48 48
17 34 51 51
I have a big matrix (8656x25960) with some speckle noise within it. I used the findpeaks tool in order to find in what columns I indeed have peaks above a certain threshold. The output of the findspeaks tool is a matrix containing all of the bad columns, for example -
loc =
Columns 1 through 6
30 51 155 307 333 338
Columns 7 through 12
642 955 1409 1567 1728 1730
Columns 13 through 18
2332 2546 2615 2685 2806 2995
Columns 19 through 24
3002 3122 3124 3164 3690 4176
Columns 25 through 30
4430 4475 4539 5142 5155 5244
Columns 31 through 36
5246 5941 5943 6114 6486 6922
Columns 37 through 42
7165 7169 7460 7587 7647 8944
Columns 43 through 44
12754 13693
How can I use those columns numbers with the original matrix and replace the values of this 'bad' column with the value 0 (for example).
Hoping I'm clear enough.
For row vector Ioc simply use indexing:
yourmatrix(:,Ioc) = 0;
In MATLAB (R2015a), I have two large matrices that can be simplified as:
A = [ 24 10 830; 24 15 830; 150 17 945; 231 40 1130; 231 45 1130]
(note that in A, column 3 is the time for the event cataloged in column 1) and
B = [24 13; 150 29; 231 43]
How can I match and copy the time-data from column 3 in matrix A, to a matching and filtered event column in matrix B?
For example, I want the value 24 from first column in B to be matched with value 24 from first column in A, and then copy the corresponding time-data in A's third column (for 24 it's 830, for 150 it's 945 etc.) into B. This should result into our new B with the time-data from A:
B = [24 13 830; 150 29 945; 231 43 1130]
I relatively new to MATLAB so any help is much appreciated!
First find the location of the elements in the first row of B in the first row of A using the ismember function. And then use those locations to construct the new matrix.
[~,Locb] = ismember(B(:,1),A(:,1));
Bnew = [B A(Locb,3)]
Bnew =
24 13 830
150 29 945
231 43 1130
This is a fast way that comes to my mind. There might be some singularities that needed to be checked more thoroughly.
date time machine power energy heat
? ? ? MW kJ kJ
2/15/2016 20:50:46 kuka 45 22 22
2/15/2016 20:50:47 kuka 50 24 22
2/15/2016 20:50:48 kuka 56 26 22
2/15/2016 20:50:49 kuka 58 28 22
2/15/2016 20:50:50 kuka 62 30 22
2/15/2016 20:50:51 kuka 60 32 22
2/15/2016 20:50:52 kuka 64 34 20
I have a textfile and I imported data using importdata() command in matlab
I have tried Delimiter with space ' ' and '\t'
All data is saved in a struct as fine I as need but the problem is in the first line all of it is saved in one cell like date time machine power energy heat
All of the other data like ? , MW , KJ and 45 are save in separate cells which are fine.
I want data from the first row as separate entities like data time machine etc
If I save that cell in a variable name X then output is like 'date time machine power energy heat'
When I check class of this its char
What I want know is to convert this char to a string so that I can continue writing code for my GUI
Answering after your comment
d = X{1}
Take any variable like Z use textscan to get your desired result
Z = textscan(d , '%s');
This will make Z a cell of order (1 X 1)
Z{1}(1) will be date
Z{1}(2) will be time
Z{1}(3) will be machine
......
suppose i have a .csv file And it has the values as follows:
A 23 45
B 69 84
C 48 78
D 12 34
so it has two columns. Now what i need to do is to add values staring from the 3rd column with out deleting the values in the 1st and 2nd columns..
i tried z code
fileID = fopen('exp.csv','A');
fprintf(fileID,' %12.4f\n',D);
fclose(fileID);
But the issue is that this is added all in one column like:
23
69
48
12
......
45
84
75
38
How can i do this...??
Use the csvread / csvwrite functions to load in the existing file, append a column, and write the new data.
data = csvread('exp.csv');
toadd = (1:4)';
newdata = [data toadd];
csvwrite('out.csv', newdata);