How can i multiply every row to row values?
2 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
I am looking for a way to multiply one row values with every row values.
Let's assume we have:
A=[1 2 3;
4 5 6;
7 8 9]
B=[a b c]
I am looking for a way to have:
C=[1*a 2*b 3*c;
4*a 5*b 6*c;
7*a 8*b 9*c]
Thanks in advance for your comments.
0 commentaires
Réponse acceptée
dpb
le 3 Jan 2021
>> A=reshape(1:9,3,[])
A =
1.00 4.00 7.00
2.00 5.00 8.00
3.00 6.00 9.00
>> B=1:3;
>> A.*B
ans =
1.00 8.00 21.00
2.00 10.00 24.00
3.00 12.00 27.00
>>
Works after TMW implemented automagic vector expansion -- I don't recall which release but has been a few cycles now.
If the above doesn't work on your version, use bsxfun
12 commentaires
dpb
le 5 Jan 2021
That's what I just did above except for the full array -- the row of logical True shows every element matches to machine precision.
>> load y_send.mat
>> c1=ones(1,4);
>> demultiplex_data_y1=bsxfun(@times,c1,y_send);
>> all(y_send(:)==demultiplex_data_y1(:))
ans =
logical
1
>>
Explicitly using the variables instead...same result.
>> demultiplex_data_y1([1:5 end-5:end],:)
ans =
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
1.00 1.00 -1.00 3.00
-1.00 -1.00 -3.00 1.00
-1.00 -1.00 -3.00 1.00
-1.00 -1.00 -3.00 1.00
1.00 -3.00 -1.00 -1.00
1.00 -3.00 -1.00 -1.00
>> y_send([1:5 end-5:end],:)
ans =
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
-3.00 1.00 -1.00 -1.00
1.00 1.00 -1.00 3.00
-1.00 -1.00 -3.00 1.00
-1.00 -1.00 -3.00 1.00
-1.00 -1.00 -3.00 1.00
1.00 -3.00 -1.00 -1.00
1.00 -3.00 -1.00 -1.00
>>
First and last rows of both arrays -- identical as all() already told us.
Whatever you're looking at, bsxfun isn't the problem.
Or, if you can run the above test and show that
all(y_send(:)==demultiplex_data_y1(:))
returns anything other than a logical TRUE (1), then you have uncovered a bug in your release of MATLAB and should upgrade (which really should do, anyways).
dpb
le 5 Jan 2021
Modifié(e) : dpb
le 5 Jan 2021
Try the following modification to your program and see what happens there...
load('y_send.mat');
y_send;
bit = 4;
levels = 16;
Fs = 44100;
len = length(y_send);
t = 0:1/Fs:(len-1)/Fs;
max_x = 1;
min_x = -1;
step=(max_x-min_x)/levels;
c1 = [ 1 1 1 1 ];
%row to row and bit to bit multiplication of y_send and c1.
demultiplex_data_y1 = bsxfun(@times, c1, y_send);
demultiplex_data_y1;
if any(demultiplex_data_y1(:)~=y_send(:))
disp('ERROR! bsxfun() times failure with unity multiplier')
else
disp('SUCCESS! bsxfun() times with unity multiplier returns original')
end
...
Running it here resulted in
>> receive_cdm
SUCCESS! bsxfun() times with unity multiplier returns original
>>
Plus de réponses (0)
Voir également
Catégories
En savoir plus sur Creating and Concatenating Matrices dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!