Find and report the distance between two points along a route

Procedure

Code:

/*----------------------------- Author --------------------------------------
/*
/*Original Coding:      ESRI
/*
/*----------------------------- Name ----------------------------------------
/*
/*MEASURE_PT_DISTANCE.AML
/*Copyright, 1994, Environmental Systems Research, Institute, Inc.
/*
/*----------------------------- Purpose -------------------------------------
/*This AML will allow a user to interactively select two points along a 
/*specified route and find the distance in coverage units between those
/*two points.  In order for this to work properly, the route system must be
/*built already, and measures assigned.
/*
/*---------------------------- Usage ----------------------------------------
/*
/* MEASURE_PT_DISTANCE < COVERAGE >  
/*
/*-------------------------- Disclaimer -------------------------------------
/*You may use, copy, modify, merge, distribute, alter, reproduce and/or 
/*create derivative works of this AML for your own internal use.  All rights 
/*not specifically granted herein are reserved to ESRI.
/*
/*THIS AML IS PROVIDED "AS-IS" WITHOUT WARRANTY OF ANY KIND, EITHER  
/*EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED  
/*WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
/*PURPOSE, WITH RESPECT TO THE AML.
/*
/*ESRI shall not be liable for any damages under any theory of law related 
/*to your use of this AML, even if ESRI is advised of the possibilites of 
/*such damage.  This AML is not supported by ESRI.
/*---------------------------- Arguments ------------------------------------
/*
/*       .cov           input coverage
/*       .rsys          name of route system
/*
/*------------------------ Global Variables ---------------------------------
/*
/*       .cov           input coverage
/*       .rsys          name of route system
/*
/*------------------------ Local Variables ----------------------------------
/*
/*       distA          distance measured to first point along route
/*       distB          distance measured to second point along route
/*       length         distance between two points
/*
/*---------------- Input/Output Files, Coverages, etc. ----------------------
/*----------------- Detailed Remarks, Assumptions, etc. ---------------------
/*
/* [show measure route] returns key,route_number, measure_value
/*
/*----------- Other AMLs, Menus, or Programs Run from this AML --------------
/*----------- Other AMLs, Menus, or Programs which Run this AML -------------
/*-------------------- Operating System Dependencies ------------------------
&args .cov .rsys
measure route %.cov% %.rsys%
&s distA [extract 3 [show measure route]]
measure route %.cov% %.rsys%
&s distB [extract 3 [show measure route]]
&s length [calc %distB% - %distA%]
&type The distance between those points is, %length%...
&return
/*--------------------------------------------------------------------------
/*
&severity &error &routine bailout 
&call exit
&return 
/*
/* ---------------------------- Routine Usage --------------------------------
/*
&routine usage
&type Usage: &run MEASURE_PT_DISTANCE.AML
&return
/*
/* ---------------------------- Routine Exit ---------------------------------
/*
&routine exit
&return
/*
/* --------------------------- Routine Bailout -------------------------------
/*
&routine bailout
&severity &error &ignore
&call exit
&return; &return &error Bailing out of MEASURE_PT_DISTANCE.AML...
/* End of AML.