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