In many computer languages (such as FORTRAN or Mathematica), the common residue of b (mod m) is written mod(b, m) (FORTRAN) or Mod[b, m] (Mathematica).
The function is related to the floor function
by
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|
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where

Since usage concerning fractional part/value and integer part/value can be confusing, the following table gives a summary of names and notations used (D. W. Cantrell, pers. comm.). Here, S&O indicates Spanier and Oldham (1987).
notation | name | S&O | Graham et al. | Mathematica |
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ceiling function | -- | ceiling, least integer | Ceiling[ x] |
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congruence | -- | -- | Mod[ m, n] |
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floor function | ![]() |
floor, greatest integer, integer part | Floor[ x] |
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fractional value | ![]() |
fractional part or ![]() |
no name |
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fractional part | ![]() |
no name | FractionalPart[ x] |
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integer part | ![]() |
no name | IntegerPart[ x] |
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nearest integer | -- | -- | Round[ x] |
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quotient | -- | -- | Quotient[ m, n] |
Ceiling Function, Common Residue, Congruence, Fractional Part, Integer Part, Minimal Residue, Nearest Integer, Quotient, Residue