Create an attribute expression on a chart axis

An attribute expression is a mathematical combination of attributes in the database, representing a performance index or a user-defined attribute. Examples include the specific strength σ_y / ρ (σ_y is the yield strength and ρ is the density), and the performance index for a light stiff beam E^1/2 / ρ (E is the Young's Modulus).

You can plot an attribute expression on a chart axis, and compare two complex requirements on one selection chart.

To create an attribute expression, in the Chart Settings dialog, click Advanced. The expression is displayed in the top pane. To add an operator (plus, minus, multiply etc.) to the expression, click the operator buttons below the expression pane. Click to see an example expression in the dialog.

Only numerical attributes, constants, and parameters can be combined in an expression.

Add a logarithm to the expression

• For a logarithm with base 10, type log() into the top pane, and insert the attribute inside the parentheses e.g. log([Density])
• For a logarithm with base e, type ln() into the top pane, and insert the attribute inside the parentheses e.g. ln([Density])

Add an attribute to the expression

1. Click the Attributes tab.
2. Select an attribute category from the list, if desired.
3. Select one or more attributes and click Insert.

   The attribute will appear in the top pane at. For example: [Young's modulus]

Add a constant or a parameter to the expression

1. Click the Constants/Parameters tab.
2. Select Constants or Parameters from the list.
3. Select an item and click Insert.

   The constant or parameter will appear in the top pane. For example: [Constant:Rest Mass of Electron]

Add record branches to the expression

1. Click the Trees tab.
2. Select the tree to be plotted from the list.
3. Locate and select the branch of interest and click Insert.

   The branch will appear in the top pane. For example: [MaterialUniverse:\Metals and alloys\Precious metal alloys]