Differences

This shows you the differences between two versions of the page.

--- parameters [2015/05/17 16:31] – dmitry
+++ parameters [2015/05/19 19:29] – dmitry
@@ Line 2: / Line 2: @@
 (available from version 1.6)
-Parameters can be used to parametrize project calculation (e.g. file names, dates, multipliers and ratios in expressions, etc.).
+Parameters can be used to parametrize transformations and expressions instead of file names in export/import transformations and instead of constants in expressions (e.g. multipliers and ratios). See [[syntax:|expression syntax]] for using parameters in expressions.
+Parameters are global for a project, which means that they are available for all tables. Value of a parameter is the same for all tables. Changing a parameter value doesn't automatically discard transformation results, but all new calculations will use the new value (where applicable).
 === Parameter editor ===
@@ Line 12: / Line 14: @@
   * **File name** - this parameter type is just like a text parameter but for convenience the input box has buttons for opening file browser and triggering absolute/relative paths
   * **Date** - it's a number parameter that supposed to indicate a date that can be chosen using a date picker (calendar)
-  * **Calculated parameter** can be calculated using [[syntax:start|expressions]]. Although some restrictions apply -- expressions used for calculated parameters can't have field names and other calculated parameters.
+  * **Calculated parameter** can be calculated using [[syntax:start|expressions]]. Although some restrictions apply -- expressions used for calculated parameters can't have field names and other calculated parameters. Calculated parameters are evaluated automatically before running a project or calculating a transformation.
-=== Required parameters ===
+=== Full project runs ===
-Any parameter except calculated parameters can be marked as **required** using respective checkbox in parameter editor. All required parameters are prompted on full project runs -- i.e. when running a project with all transformations not calculated (e.g. right after opening a project) or when performing Reload and Run.
+All non-calculated parameters are prompted on full project runs -- i.e. when running a project with all transformations not calculated (e.g. right after opening a project) or when performing Reload and Run.
 === Command line execution ===
-Parameter values can be defined from command line. If a project has required parameters they must be defined if running in command line mode. Defining non-required parameters are optional, if such parameter wasn't defined it's default value will be used instead. Calculated parameters can't be defined from command line. New parameters can't be created from command line. See [[command_line|command line syntax]] for more details.
+Parameter values can be defined from command line. Defining parameters is optional. If a parameter isn't defined then its default value is used. Calculated parameters can't be defined from command line. Also new parameters can't be created from command line. See [[command_line|command line syntax]] for more details.