Sign switching in a sequence
3 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
I have a column vector for example,
A=[10; 30; 30; 40; 60; 70; 50; 50; 60; 20; 20]
What I want to do is count each time a number makes a transition from a smaller number to a large number, to count the numbers of times a number makes a transition from a larger number to a smaller number and the number of times the is no change in numbers.
Any help would be great thanks!
0 Kommentare
Akzeptierte Antwort
Doug Hull
am 7 Jun. 2013
Look at the diff command. It will subtract each element from the next. Look at the sign of that calculation and you will be all set.
>> A=[10; 30; 30; 40; 60; 70; 50; 50; 60; 20; 20]
A =
10
30
30
40
60
70
50
50
60
20
20
>> d = diff(A)
d =
20
0
10
20
10
-20
0
10
-40
0
>> nnz(d > 0)
ans =
5
>> nnz(d < 0)
ans =
2
>> nnz(d == 0)
ans =
3
0 Kommentare
Weitere Antworten (1)
Azzi Abdelmalek
am 7 Jun. 2013
Bearbeitet: Azzi Abdelmalek
am 7 Jun. 2013
ii=histc(sign(diff(A)),[-1;0;1])
%ii(1) correspond to switch high-low
%ii(2) no switch
%ii(3) switch low-high
doc diff
doc sign
doc histc
Siehe auch
Kategorien
Mehr zu Polynomials finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!