layout: default title: calcCost parent: Grid Tools nav_order: 9 —

calcCost

Description

calcCost is a command-line utility for performing a detailed cost-benefit analysis and logistical planning for bathymetric surveys. It takes a Digital Terrain Model (DTM) as input and evaluates the optimal sonar system (from a predefined list or user-defined specifications) for mapping different depth zones. For each pixel in the DTM, it calculates the most cost-effective sonar, the associated survey area, estimated survey days, data volume, and total cost, including transit to/from home ports. It supports various currency conversions and outputs detailed reports on survey parameters and costs.

Usage 

calcCost [OPTIONS] -dtm <dtm_file.r4> -out <params_file>

Arguments

Option Description Default / Example
-dtm <dtm_file.r4> Required. Specifies the path to the input JHC-format 32-bit floating-point DTM (.r4) file. bathymetry.r4
-out <params_file> Required. Specifies the path for the output file containing the calculated survey parameters and costs. survey_report.txt
-system <index> <descriptor_file> Defines a sonar system. <index> is a zero-based integer (0-9) to identify the sonar. <descriptor_file> is an ASCII file specifying the sonar’s characteristics (draft, min/max depth, angular sector, max width, speed, efficiency, day rate, mission endurance, transit speed/dayrate). This option can be used multiple times to define different sonar systems. -system 0 sonar_a.txt
-ports <portsfile> Specifies an ASCII file containing a list of home port locations (name, latitude, longitude) from which transit costs will be calculated. home_ports.txt
-mindepth <value> Sets a minimum depth threshold (meters). Pixels shallower than this will not be surveyed. 0.0
-maxdepth <value> Sets a maximum depth threshold (meters). Pixels deeper than this will not be surveyed. 20000.0
-IRP Set output currency to Irish Pound.  
-NZD Set output currency to New Zealand Dollar.  
-CAN Set output currency to Canadian Dollar.  
-USD Set output currency to US Dollar.  
-UKP Set output currency to UK Pound.  
-v Enable verbose output during processing.  

How It Works

  1. Input Loading: Reads the input DTM (-dtm) and optionally a portsfile (-ports). It also reads descriptor_files for each sonar system defined by -system.
  2. DTM Iteration: For each pixel in the DTM that falls within the mindepth and maxdepth thresholds:
    • It determines the water depth at that pixel.
    • For each defined sonar system, it checks if that system is capable of surveying at the current water depth and calculates the effective swath width and survey efficiency.
    • It then calculates the survey area, estimated survey days, and data volume.
    • If portsfile is provided, it calculates transit costs to/from the nearest port.
    • It identifies the most cost-effective sonar system for that pixel.
  3. Cost Aggregation: The tool aggregates survey parameters and costs for each sonar system and for the overall survey area.
  4. Currency Conversion: Converts costs to the specified output currency (IRP, NZD, CAN, USD, UKP).
  5. Output Report: Generates a detailed ASCII report (-out) containing:
    • Summary of the survey area and total cost.
    • Breakdown of costs by sonar system.
    • Estimated survey days and data volume.
    • Maps (if implemented) showing optimal sonar choice per pixel.

Output Files

  • <params_file>: An ASCII file detailing the calculated survey parameters and costs.

Dependencies

  • array.h: For JHC_header structure and DTM data handling.
  • support.h: For general utility functions and error handling.
  • j_proj.h: For coordinate projection, used in distance calculations.

Notes

This tool is highly configurable and can be used for detailed pre-survey planning and resource allocation. The accuracy of the cost estimates depends heavily on the quality of the sonar descriptor_files and portsfile data. The various currency conversion options make it suitable for international use.