gcalccmd

gcalccmd [OPTION...] [EXPRESSION]

-e, --expression=EXPRESSION
    Evaluates the given mathematical EXPRESSION and prints the result to standard output. This is the primary way to specify the calculation.

-s, --set-mode=MODE
    Sets the calculator's operational MODE. Common modes include basic, scientific, financial, and programming. This influences how expressions are interpreted and what functions are available.

-u, --show-units
    Displays a list of all supported unit conversions and their corresponding symbols.

-p, --show-plugins
    Lists all available calculator plugins, which extend functionality, such as currency conversion or specific financial tools.

-v, --version
    Prints the version information for gcalccmd and exits.

--help
    Displays a help message with available options and command usage, then exits.

gcalccmd is a command-line utility that provides direct access to the powerful calculation engine of the GNOME Calculator.

It enables users to perform a wide range of mathematical, scientific, financial, and programming calculations directly from the terminal, bypassing the need to launch the full graphical application. This makes it ideal for quick evaluations, shell scripting, and integration into automated workflows. Users simply input a mathematical expression as an argument, and gcalccmd processes it, returning the calculated result to standard output. It supports a vast array of functions, constants, and unit conversions, adapting its capabilities based on the selected mode. Its efficiency and versatility make it a valuable tool for diverse computational needs on a Linux system.

gcalccmd relies on the underlying gnome-calculator libraries. If gnome-calculator is not installed or its libraries are not accessible, gcalccmd may not function correctly or might not be available on the system. The exact set of supported functions, units, and calculation modes is dependent on the version of gnome-calculator and its loaded plugins. Error messages for invalid expressions can sometimes be generic, requiring familiarity with GNOME Calculator's expression syntax.

Here are some common ways to use gcalccmd:

Basic arithmetic:
gcalccmd "2 + 2"
gcalccmd "(5 * 8) / 4"

Scientific calculations:
gcalccmd --set-mode=scientific "sqrt(16)"
gcalccmd --set-mode=scientific "sin(pi/2)"

Programming mode (base conversions, bitwise ops):
gcalccmd --set-mode=programming "0xFF + 0o77"
gcalccmd --set-mode=programming "10 << 2"

Unit conversions:
gcalccmd "10 USD to EUR"
gcalccmd "100 km to miles"

gcalccmd supports various operational modes, similar to its graphical counterpart, configurable via the --set-mode option:
basic: For simple arithmetic operations.
scientific: Enables advanced mathematical functions like trigonometry, logarithms, exponentials, and constants like pi.
financial: Provides functions for financial calculations such as loan payments, compound interest, and depreciation.
programming: Allows calculations in different number bases (binary, octal, decimal, hexadecimal) and supports bitwise operations.
The availability of modes and functions depends on the installed plugins and version of gnome-calculator.

gcalccmd is an integral component of the GNOME desktop environment, specifically designed to offer a non-graphical, command-line interface to the robust gnome-calculator backend. Its development has evolved alongside GNOME Calculator itself, providing a consistent and programmatic way to access its extensive features for shell scripting, quick calculations, and integration into larger automation tasks without the overhead of launching a graphical window. It serves as a bridge for command-line users to leverage the powerful capabilities of the GNOME Calculator.

gnome-calculator(1), bc(1), dc(1), expr(1)