f(x)Expressions

You can plot an expression or common futures spread by clicking on the "f(x)" button.

Open

The Expressions dialog allows you to choose from a number of popular commodity spreads. When you select a popular spread from the drop-down list, the expression is built automatically for you. You may also create your own custom spread chart by entering the mathematical calculation.

Open

The calculated results are displayed as a line chart. Additionally, an expression can be added to the main chart window, or as a new pane on the chart (you'll choose the placement when you create the expression).

If you want to create your own custom expression, you can enter the calculation directly into the expression field. Expressions consist of:

• symbols - must be enclosed in "curly brackets". Examples: {ZC*1} {ESU17} {IBM} {^EURUSD}

• constants: any floating point number like 2.35; note that we don't support "scientific" notation (for example 1.72E5)

• operators:

  • unary operator - (negation) so you may enter -2 + 1 and are not forced to type 1 - 2

  • binary operators:
    + (addition)

    • (subtraction) 

    • (multiplication)

     / (division)
     ^(power)
    These are listed in order from lowest to highest precedence (multiplication and division will always happen before addition and subtraction, unless grouped by parentheses).

  • to make sure precedence is correct, parentheses ( and ) can be used; for example 2 ^ 2 + 3 = 7 but 2 ^ (2 + 3) = 32