Filter löschen
Filter löschen

How to calculate moving average

307 Ansichten (letzte 30 Tage)
Mekala balaji
Mekala balaji am 16 Nov. 2017
Bearbeitet: dpb am 25 Nov. 2020
Hi,
I have following data:
0.10
0.24
0.30
0.25
0.33
0.35
0.46
0.47
0.48
0.51
0.52
0.53
0.53
0.57
0.58
0.58
0.58
0.59
0.63
0.64
0.66
0.72
I want to take 3-points moving average,
Please help some one
  2 Kommentare
Quin Silk
Quin Silk am 11 Dez. 2019
Can someone write code to do it without using movmean?
Star Strider
Star Strider am 11 Dez. 2019
@Quin Silk — See the Moving Average Filter link in my Answer.

Melden Sie sich an, um zu kommentieren.

Antworten (6)

Bandar
Bandar am 11 Dez. 2019
Take a look this data
file=[1 2 3 4];
movmean(file,3)
which returns
1.5000 2.0000 3.0000 3.5000
The filter works as follows:
1 2 (1+2)/2 = 1.5 when k points at 1
1 2 3 (1+2+3)/3 = 2.0 when k points at 2
2 3 4 (2+3+4)/3 = 3.0 when k points at 3
3 4 (3+4)/2 = 3.5 when k points at 4
Now it is easy to convert it to a logical code or merely use movmean().
  3 Kommentare
Bandar
Bandar am 11 Dez. 2019
A=[1 2 3 4 5 6];
m=ones(1,length(A));
for i=1:length(A)
if i == 1
m(i) = (A(i)+A(i+1))/2;
elseif i == length(A)
m(i) = (A(i-1)+A(i))/2;
else
m(i) = (A(i-1)+A(i)+A(i+1))/3;
end
end
movmean(A,3)
m
Micheal Omojola
Micheal Omojola am 8 Sep. 2020
@Bandar Aldhafeeri: Thank you! Your answer was helpful.

Melden Sie sich an, um zu kommentieren.


KL
KL am 16 Nov. 2017
If you have 2016b or later, use movmean,
mean_arr = movmean(your_array,3)

Star Strider
Star Strider am 16 Nov. 2017
Use the movmean (link) function (introduced in R2016a).
You can also use the filter function. See the section on Moving-Average Filter (link).
  1 Kommentar
Pallavi Bharati
Pallavi Bharati am 25 Nov. 2020
How to do centered moving average ...three point centred moving average in matlab without the movmean command as i have matlab 2015

Melden Sie sich an, um zu kommentieren.


dpb
dpb am 16 Nov. 2017

Sudhakar Rayabarapu
Sudhakar Rayabarapu am 8 Sep. 2018
Bearbeitet: Sudhakar Rayabarapu am 8 Sep. 2018
Name your data array A; and keep as a column; then use this command
OutPut = tsmovavg(A, 's', 3, 1)
this will give you the simple moving average

Pallavi Bharati
Pallavi Bharati am 24 Nov. 2020
Can anyone help me to compute three point moving average of a 5 year data.I used the filter command but the result are erroneous .I am using MATLAB 2015.And I have a huge data 5 year day wise data and i have to compute three point moving average for each month .
  2 Kommentare
Pallavi Bharati
Pallavi Bharati am 24 Nov. 2020
Using looping can be erroneous for so large data please suggest something else
dpb
dpb am 24 Nov. 2020
Bearbeitet: dpb am 25 Nov. 2020
The results aren't "erroneous" (presuming you defined the coefficients correctly), they just depend on how one treats the end conditions...examine the following:
>> x=1:10;
>> movmean(x,3)
ans =
1.5000 2.0000 3.0000 4.0000 5.0000 6.0000 7.0000 8.0000 9.0000 9.5000
>> filter(ones(1,3)/3,1,x)
ans =
0.3333 1.0000 2.0000 3.0000 4.0000 5.0000 6.0000 7.0000 8.0000 9.0000
>> conv(x,ones(1,3)/3,'same')
ans =
1.0000 2.0000 3.0000 4.0000 5.0000 6.0000 7.0000 8.0000 9.0000 6.3333
>> conv(x,ones(1,3)/3,'valid')
ans =
2.0000 3.0000 4.0000 5.0000 6.0000 7.0000 8.0000 9.0000
>>
movmean special-cases the end positions to change the divisor to match the number of elements from 2:N on each end; filter and conv do not.
It's up to you to determine the solution you wish to use; none is theoretically any more or less correct than any other; just different assumptions are made.

Melden Sie sich an, um zu kommentieren.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by