sum

问题 I want to return the sum of "amount" from my payments table. There can be many payments for one invoice. The below "->sum('amount') does not work, it returns: Call to a member function addEagerConstraints() on a non-object. How to return the sum of all payments for each invoice in my relation? Invoices Model: class Invoices extends Eloquent { public function payments() { return $this->hasMany('Payments')->sum('amount'); } } Expenses Model: class Payments extends Eloquent { public function

问题 I want to return the sum of "amount" from my payments table. There can be many payments for one invoice. The below "->sum('amount') does not work, it returns: Call to a member function addEagerConstraints() on a non-object. How to return the sum of all payments for each invoice in my relation? Invoices Model: class Invoices extends Eloquent { public function payments() { return $this->hasMany('Payments')->sum('amount'); } } Expenses Model: class Payments extends Eloquent { public function

问题 I want to return the sum of "amount" from my payments table. There can be many payments for one invoice. The below "->sum('amount') does not work, it returns: Call to a member function addEagerConstraints() on a non-object. How to return the sum of all payments for each invoice in my relation? Invoices Model: class Invoices extends Eloquent { public function payments() { return $this->hasMany('Payments')->sum('amount'); } } Expenses Model: class Payments extends Eloquent { public function

问题 I want to return the sum of "amount" from my payments table. There can be many payments for one invoice. The below "->sum('amount') does not work, it returns: Call to a member function addEagerConstraints() on a non-object. How to return the sum of all payments for each invoice in my relation? Invoices Model: class Invoices extends Eloquent { public function payments() { return $this->hasMany('Payments')->sum('amount'); } } Expenses Model: class Payments extends Eloquent { public function

问题 I have a vector with zeros and positives numbers. I would simply like to sum the numbers that are between the zeros. A simple example: x <- c(0,0,0,0,0,1,23,24,54,12,1,23,0,0,0,0,1,23,56,76,0,1,13) That is, I want to sum the elements 1,23,24,54,12,1,23 , 1,23,56,76 and 1,13 . My desired output would therefore be: 138 , 156 and 14 . I found this really similar question but it is on Python: Sum elements of a list between zeros in Python Thanks. 回答1: We can use tapply , creating groups with

来源： https://stackoverflow.com/questions/56194189/is-omn-the-same-as-omaxm-n

来源： https://stackoverflow.com/questions/56194189/is-omn-the-same-as-omaxm-n

来源： https://stackoverflow.com/questions/64358157/sum-of-digits-of-an-integer

来源： https://stackoverflow.com/questions/64794361/creating-rolling-periods

来源： https://stackoverflow.com/questions/51186922/moving-sum-of-a-certain-window-in-r