Expressions - pwdlugosz/Rye GitHub Wiki

#Scalar Expressions

    • : traditional addition for doubles and integers, concatenates strings and blobs, adds ticks to dates, and returns null for bool.
    • : traditional subtraction for doubles and integers, calculates the difference in ticks for dates, returns null otherwise.
    • : traditional multiplication for doubles and integers, returns null otherwise.
  • / : traditional division for doubles and integers, returns null otherwise.
  • /? : traditional division, but returns 0 if the denominator is 0 rather than null.
  • % : traditional modular arithmetic for integers and doubles, returns null otherwise.
  • ^ : raises a number to a power.

  • , <, >=, <= : traditional comparisons.

  • == , != : equals and not equals
  • AND, OR, XOR : traditional Boolean operations.
  • !, -, + : unary operators, where '!' is the 'not' operator.
  • X IS NULL : true if X is null, false otherwise.
  • X ?? Y : returns X if X is not null, returns Y otherwise.
  • X ? Y : Z : C/C++/C# style 'if', returns Y if Z is true and Y otherwise.
  • X -> type : casts the variable X to a new type.
  • CASE WHEN ... THEN ... WHEN ... THEN ... ELSE : traditional SQL style case statement; optimized better than nested ifs.
  • X[a] and X[a,b] : returns either the (a,0) or (a,b) element in a cell matrix.
  • Standard function library (coming soon ...)

Note about 'IF': the action 'IF', which is a control statement, uses the syntax 'IF-THEN-ELSE'. The expression 'IF' uses the '?' and ':' operators. You cannot interchange them, meaning 'IF-THEN-ELSE' tells the compiler you want to do something, where '?-:' tells the compiler you want to return something.

#Matrix Operations

    • : Adds two matrices.
    • : Subtracts two matrices.
    • : Akin to adding, multiplies each element in A with the corresponding element in B. Not true matrix multiplication.
  • / : Divides each element in a matrix with the corresponding element in another matrix.
  • /? : Performs the check divide (described above) for each element in both matrices.
  • ** : True matrix multiplication.
  • ! : Inverts a matrix (unary operation)
  • ~ : Transposes a matrix (unary operation)
    • : Negates each element in a matrix (unary operation)
  • For +, -, *, /, and /?, the user can operate on scalar x matrix or matrix x scalar, and the operation will be performed on each matrix element.
  • The function IDENTITY(type, X) returns an identity matrix with diagonal equal to X.