Custom Metrics

metrics provide a quantitative summary of how options interact with key constraints, offering insights such as material cost, technical challenges, and impacts to protected environmental areas standard metrics are automatically calculated by optioneer, while custom metrics are user configured to better reflect a project's specific screening criteria examples include a sum of major crossings total distance through designated environmental areas embedded carbon estimates percentage of route passing through a specific layer or elevation band creating a custom metric you can create and manage custom metrics from the results library, where they are listed under metrics on the right hand side open custom metrics to view a table of all existing custom metrics in your project, including their names, descriptions, and expressions click define custom metric to create a new one there is no limit to the number of custom metrics you can create give your metric a name, description, and expression use @\[metricname] to reference an existing metric, or search for one using the search bar accepted operations within an expression are + / () for a full list of accepted operators and functions, see the following section to edit or delete an existing custom metric, click the icon to the right of the metric once saved, your custom metric can be viewed from the edit columns dropdown in the results library, or from the metrics dropdown in analysis > option comparison note custom metrics only return valid results if all referenced metrics have values a null result may occur if there are no relevant features within the selected option, or if the metric layer was not included in the configuration for that option top tip to quickly access your custom metrics, add them to a docid\ ytdx6cjdqjdee057ak6i8 view see saved metrics for more information operators and functions when defining a custom metric, you can use the following arithmetic operators and built in functions operator / function syntax description addition + subtraction multiplication division / grouping () groups operations to control order of evaluation average avg(metric a, metric b, …) returns the mean value of the selected metrics maximum max(metric a, metric b, …) returns the highest value among the selected metrics minimum min(metric a, metric b, …) returns the lowest value among the selected metrics any any(metric a, metric b, …) returns 1 if at least one metric is fulfilled, otherwise returns 0 all all(metric a, metric b, …) returns 1 if all metrics are fulfilled, otherwise returns 0 troubleshooting errors if an expression is invalid, optioneer will display the following error invalid expression syntax when parsing to resolve this, check the following is the expression complete? ensure all parentheses are closed and all functions are used correctly are all metric names typed correctly? names are case sensitive are there any duplicate or misplaced symbols? check for extra commas, missing operators, or unclosed parentheses best practices for custom metrics use 3d metrics when relevant — optioneer provides both 2d and 3d versions of certain metrics where topography is a factor, prefer the 3d version for example, use total length 3d \[m] instead of total length 2d \[m] follow consistent naming conventions — include units in square brackets for clarity and align with optioneer's naming style to avoid confusion support data driven decision making — custom metrics provide quantifiable screening criteria that reduce subjectivity consider whether any manual or qualitative steps in your methodology could be streamlined with a custom metric common custom metrics custom metrics vary project by project, but some common use cases include least cost path calculates the length cost ratio for an option (total length 3d \[m] / cost \[currency]) environmental impact score combines environmental metrics to express the proportion of an option passing through protected areas as a percentage (overall distance through layer special area of conservation (sac) \[m] + overall distance through layer special protection areas (spa) (100m buffer) \[m] + overall distance through layer national nature reserve (nnr) \[m]) / total length 3d \[m]) 100 number of features within a given distance an aggregate score counting how many gis features fall within a specified buffer distance of an option's centerline useful for identifying options that pass on or near high sensitivity features such as scheduled monuments number of scheduled monuments within 250 0m of centreline \[count] + number of gardens and designed landscapes within 250 0m of centreline \[count] major crossings an aggregate score combining metrics for gis layers considered high risk crossings overall number of crossings a road \[count] + overall number of crossings gas pipeline \[count] + overall number of crossings railways \[count] modify these as needed to suit your project's specific screening criteria