What does the notation of $1{a_i=b}$ mean in a summation?
0
$begingroup$
As seen in:
http://stanford.edu/~cpiech/cs221/img/kmeansMath.png
Does it mean sum for all elements that satisfy the condition? What does the 1 mean? Is there a name for this notation?
summation notation
asked Dec 11 '18 at 18:12
johan456789johan456789
11
$endgroup$
add a comment |
0
$begingroup$
As seen in:
http://stanford.edu/~cpiech/cs221/img/kmeansMath.png
Does it mean sum for all elements that satisfy the condition? What does the 1 mean? Is there a name for this notation?
summation notation
asked Dec 11 '18 at 18:12
johan456789johan456789
11
$endgroup$
$begingroup$
Seems like the indicator function. It is 1 if $c^{(i)}=j$, 0 otherwise.
$endgroup$
– Eduardo Elael
Dec 11 '18 at 18:15
$begingroup$
en.wikipedia.org/wiki/Indicator_function
$endgroup$
– pwerth
Dec 11 '18 at 18:15
add a comment |
0
0
0
$begingroup$
As seen in:
http://stanford.edu/~cpiech/cs221/img/kmeansMath.png
Does it mean sum for all elements that satisfy the condition? What does the 1 mean? Is there a name for this notation?
summation notation
asked Dec 11 '18 at 18:12
johan456789johan456789
11
$endgroup$
As seen in:
http://stanford.edu/~cpiech/cs221/img/kmeansMath.png
Does it mean sum for all elements that satisfy the condition? What does the 1 mean? Is there a name for this notation?
summation notation
summation notation
asked Dec 11 '18 at 18:12
johan456789johan456789
11
asked Dec 11 '18 at 18:12
johan456789johan456789
11
asked Dec 11 '18 at 18:12
johan456789johan456789
11
asked Dec 11 '18 at 18:12
johan456789johan456789
11
asked Dec 11 '18 at 18:12
johan456789johan456789
11
11
$begingroup$
Seems like the indicator function. It is 1 if $c^{(i)}=j$, 0 otherwise.
$endgroup$
– Eduardo Elael
Dec 11 '18 at 18:15
$begingroup$
en.wikipedia.org/wiki/Indicator_function
$endgroup$
– pwerth
Dec 11 '18 at 18:15
add a comment |
$begingroup$
Seems like the indicator function. It is 1 if $c^{(i)}=j$, 0 otherwise.
$endgroup$
– Eduardo Elael
Dec 11 '18 at 18:15
$begingroup$
en.wikipedia.org/wiki/Indicator_function
$endgroup$
– pwerth
Dec 11 '18 at 18:15
$begingroup$
Seems like the indicator function. It is 1 if $c^{(i)}=j$, 0 otherwise.
$endgroup$
– Eduardo Elael
Dec 11 '18 at 18:15
$begingroup$
Seems like the indicator function. It is 1 if $c^{(i)}=j$, 0 otherwise.
$endgroup$
– Eduardo Elael
Dec 11 '18 at 18:15
$begingroup$
en.wikipedia.org/wiki/Indicator_function
$endgroup$
– pwerth
Dec 11 '18 at 18:15
$begingroup$
en.wikipedia.org/wiki/Indicator_function
$endgroup$
– pwerth
Dec 11 '18 at 18:15
add a comment |
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$begingroup$
Seems like the indicator function. It is 1 if $c^{(i)}=j$, 0 otherwise.
$endgroup$
– Eduardo Elael
Dec 11 '18 at 18:15
$begingroup$
en.wikipedia.org/wiki/Indicator_function
$endgroup$
– pwerth
Dec 11 '18 at 18:15