Numerical analysis: least squares method
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Basically I came up with a function where I need to approximate it using the least squares method. I had no trouble computing the constants on MATLAB and got to the following plot:
Now as you see the curves are approximately the same but not exactly. I'm looking for a rather sharp explanation to this? Is it because the function is very oscillatory? Is it because it constantly oscillates between negative and positive values? Can someone give me some insight about this? I really want to understand what I am obtaining. Thanks!
numerical-methods matlab least-squares
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
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add a comment |
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Basically I came up with a function where I need to approximate it using the least squares method. I had no trouble computing the constants on MATLAB and got to the following plot:
Now as you see the curves are approximately the same but not exactly. I'm looking for a rather sharp explanation to this? Is it because the function is very oscillatory? Is it because it constantly oscillates between negative and positive values? Can someone give me some insight about this? I really want to understand what I am obtaining. Thanks!
numerical-methods matlab least-squares
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
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2
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I think it could be good you show the function you want to fit as well as the data points. Otherwise, it could be difficult to help you. Cheers.
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– Claude Leibovici
Dec 18 '18 at 4:08
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I second Claude's suggestion.
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– timur
Dec 18 '18 at 4:10
add a comment |
$begingroup$
Basically I came up with a function where I need to approximate it using the least squares method. I had no trouble computing the constants on MATLAB and got to the following plot:
Now as you see the curves are approximately the same but not exactly. I'm looking for a rather sharp explanation to this? Is it because the function is very oscillatory? Is it because it constantly oscillates between negative and positive values? Can someone give me some insight about this? I really want to understand what I am obtaining. Thanks!
numerical-methods matlab least-squares
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
$endgroup$
Basically I came up with a function where I need to approximate it using the least squares method. I had no trouble computing the constants on MATLAB and got to the following plot:
Now as you see the curves are approximately the same but not exactly. I'm looking for a rather sharp explanation to this? Is it because the function is very oscillatory? Is it because it constantly oscillates between negative and positive values? Can someone give me some insight about this? I really want to understand what I am obtaining. Thanks!
numerical-methods matlab least-squares
numerical-methods matlab least-squares
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
asked Dec 18 '18 at 1:30
Granger ObliviateGranger Obliviate
557415
557415
2
$begingroup$
I think it could be good you show the function you want to fit as well as the data points. Otherwise, it could be difficult to help you. Cheers.
$endgroup$
– Claude Leibovici
Dec 18 '18 at 4:08
$begingroup$
I second Claude's suggestion.
$endgroup$
– timur
Dec 18 '18 at 4:10
add a comment |
2
$begingroup$
I think it could be good you show the function you want to fit as well as the data points. Otherwise, it could be difficult to help you. Cheers.
$endgroup$
– Claude Leibovici
Dec 18 '18 at 4:08
$begingroup$
I second Claude's suggestion.
$endgroup$
– timur
Dec 18 '18 at 4:10
2
2
$begingroup$
I think it could be good you show the function you want to fit as well as the data points. Otherwise, it could be difficult to help you. Cheers.
$endgroup$
– Claude Leibovici
Dec 18 '18 at 4:08
$begingroup$
I think it could be good you show the function you want to fit as well as the data points. Otherwise, it could be difficult to help you. Cheers.
$endgroup$
– Claude Leibovici
Dec 18 '18 at 4:08
$begingroup$
I second Claude's suggestion.
$endgroup$
– timur
Dec 18 '18 at 4:10
$begingroup$
I second Claude's suggestion.
$endgroup$
– timur
Dec 18 '18 at 4:10
add a comment |
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$begingroup$
I think it could be good you show the function you want to fit as well as the data points. Otherwise, it could be difficult to help you. Cheers.
$endgroup$
– Claude Leibovici
Dec 18 '18 at 4:08
$begingroup$
I second Claude's suggestion.
$endgroup$
– timur
Dec 18 '18 at 4:10