Referencing Data and Constants in Expressions

This guide explains how to reference data variables, results variables, fuel variables, and constants within expressions in the LEAP software to create models with both exogenous and endogenous variables.

• LEAP allows users to create expressions that reference two types of variables: data variables, which are specified directly in the Analysis View, and results variables, which are calculated internally by the software (e.g., total emissions or total costs).
• The general syntax for referencing a branch or variable is 'Path\Branch:Variable[Scale Unit]'. References are not case-sensitive, and LEAP automatically standardizes capitalization upon submission. Users can use shorthand for immediate siblings or parents, but must use the full path for distant branches.
• LEAP automatically appends the scale and units of a referenced variable in square brackets, which users can edit to convert values. Conversions must remain within the same unit class (e.g., mass to mass) to avoid errors. Supported scaling factors include %, Hundred, Thousand, Million, Billion, Trillion, and specifically for users in India, Lakh and Crore.
• References to data variables can be limited using a 'Tag=' filter to sum only specific branches. Additionally, users can reference fuel variables (chemical/physical characteristics like carbon content), user-defined or default molecular weight constants, and TED database variables using the TED() function.

APA

Stockholm Environment Institute (n.d.). Referencing Data and Constants in Expressions. https://leap.sei.org/Help24/Expressions/Referencing_Other_Data_Variables_in_Expressions.htm

Chicago

Stockholm Environment Institute. Referencing Data and Constants in Expressions. n.d. https://leap.sei.org/Help24/Expressions/Referencing_Other_Data_Variables_in_Expressions.htm.

Wikipedia

{{cite report |author=Stockholm Environment Institute |title=Referencing Data and Constants in Expressions |url=https://leap.sei.org/Help24/Expressions/Referencing_Other_Data_Variables_in_Expressions.htm |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stockholmenvironmentinstitutendreferencing, author = {{Stockholm Environment Institute}}, title = {{Referencing Data and Constants in Expressions}}, institution = {Stockholm Environment Institute}, url = {https://leap.sei.org/Help24/Expressions/Referencing_Other_Data_Variables_in_Expressions.htm}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }