Derivative for row vector
$begingroup$
Confused in the example 2.1 in the cs231n tutorial.
Let y be a row vector with C components computed by taking the product of another row
vector x with D components and a matrix W that is D rows by C columns, which is $y = x W$
According to the doc, $frac{dy_3}{dx_7}
= W_{7,3}$
In my understanding, $frac{dy}{dx} = W^T$, as the size of $frac{dy}{dx}$ should be C Rows by D columns, while the doc says $frac{dy}{dx} = W$
Is my understanding wrong or the doc is wrong?
matrices matrix-calculus
asked Dec 17 '18 at 3:35
KamelKamel
1013
$endgroup$
migrated from stats.stackexchange.com Dec 18 '18 at 11:10
This question came from our site for people interested in statistics, machine learning, data analysis, data mining, and data visualization.
add a comment |
$begingroup$
Confused in the example 2.1 in the cs231n tutorial.
Let y be a row vector with C components computed by taking the product of another row
vector x with D components and a matrix W that is D rows by C columns, which is $y = x W$
According to the doc, $frac{dy_3}{dx_7}
= W_{7,3}$
In my understanding, $frac{dy}{dx} = W^T$, as the size of $frac{dy}{dx}$ should be C Rows by D columns, while the doc says $frac{dy}{dx} = W$
Is my understanding wrong or the doc is wrong?
matrices matrix-calculus
asked Dec 17 '18 at 3:35
KamelKamel
1013
$endgroup$
migrated from stats.stackexchange.com Dec 18 '18 at 11:10
This question came from our site for people interested in statistics, machine learning, data analysis, data mining, and data visualization.
add a comment |
$begingroup$
Confused in the example 2.1 in the cs231n tutorial.
Let y be a row vector with C components computed by taking the product of another row
vector x with D components and a matrix W that is D rows by C columns, which is $y = x W$
According to the doc, $frac{dy_3}{dx_7}
= W_{7,3}$
In my understanding, $frac{dy}{dx} = W^T$, as the size of $frac{dy}{dx}$ should be C Rows by D columns, while the doc says $frac{dy}{dx} = W$
Is my understanding wrong or the doc is wrong?
matrices matrix-calculus
asked Dec 17 '18 at 3:35
KamelKamel
1013
$endgroup$
Confused in the example 2.1 in the cs231n tutorial.
Let y be a row vector with C components computed by taking the product of another row
vector x with D components and a matrix W that is D rows by C columns, which is $y = x W$
According to the doc, $frac{dy_3}{dx_7}
= W_{7,3}$
In my understanding, $frac{dy}{dx} = W^T$, as the size of $frac{dy}{dx}$ should be C Rows by D columns, while the doc says $frac{dy}{dx} = W$
Is my understanding wrong or the doc is wrong?
matrices matrix-calculus
matrices matrix-calculus
asked Dec 17 '18 at 3:35
KamelKamel
1013
asked Dec 17 '18 at 3:35
KamelKamel
1013
asked Dec 17 '18 at 3:35
KamelKamel
1013
asked Dec 17 '18 at 3:35
KamelKamel
1013
asked Dec 17 '18 at 3:35
KamelKamel
1013
1013
migrated from stats.stackexchange.com Dec 18 '18 at 11:10
This question came from our site for people interested in statistics, machine learning, data analysis, data mining, and data visualization.
migrated from stats.stackexchange.com Dec 18 '18 at 11:10
This question came from our site for people interested in statistics, machine learning, data analysis, data mining, and data visualization.
add a comment |
add a comment |
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