MongoDB $trunc

In MongoDB, the $trunc aggregation pipeline operator truncates a number to a whole integer or to a specified decimal place.

You have the option of specifying how many decimal places for which to truncate the number. To do this, pass a second argument. The first argument is the number to truncate, and the second (optional) argument is the number of decimal places to truncate it to.

Omitting the second argument truncates all digits to the right of the decimal and returns the whole integer value.

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MongoDB $mod

In MongoDB, the $mod aggregation pipeline operator divides one number by another and returns the remainder.

To use $mod, pass the two numbers in an array. The $mod operator will divide the first number by the second number and return the remainder. In other words, the first number is the dividend, and the second number is the divisor.

The arguments can be any valid expression as long as they resolve to numbers.

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