max — GTM Variable Template for Number

max CORE Number

Direct (.tpl) Apply (.tpl)

Returns the maximum (largest) value from an array of numbers.

When to Use This

Number Operations

Arithmetic, rounding, clamping, and mathematical transformations on numeric values.

Filtering

Select or exclude items from collections based on criteria or predicates.

Examples

Maximum of positive numbers

INPUT

add: []

OUTPUT

Maximum with negatives

INPUT

add: [{arg: -1}]
Numbers to Compare: [{arg: -5}, {arg: -2}, {arg: -10}, {arg: -1}]

OUTPUT

-1

GTM Configuration

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max

Numbers to Compare

⊖

Input Setup

Input Function (optional)

⚙️ Optional pre-processing function applied to the extracted numbers array before finding the maximum (e.g., filter values, transform array). Note: Values are extracted from the table's argument property before this function is applied.

Result Handling

Output Function (optional)

⚙️ Optional function to apply to the maximum value before returning it (e.g., val => val * 2, val => Math.round(val)). Useful for chaining transformations on the output.

Numbers to Compare list

🔗 Result Handling — Chain Variables

max()

Related Variables

Same category: Number

Under the Hood

📜 View Implementation Code

/**
 * Returns the maximum value from an array of numbers.
 * 
 * @param {Array} data.src - Array of objects with 'arg' property (Direct mode) or array of numbers (Apply mode).
 * @param {Array} data.add - Additional numbers to include in the comparison (Apply mode only).
 * @param {Function|string} [data.out] - Optional output handler: function to transform result or string with format.
 *
 * Direct-mode specific parameters:
 * @param {Function} [data.pre] - Optional pre-processor function to transform src before processing.
 * 
 * @returns {number} The maximum value found, or NaN if the array is empty or contains no valid numbers.
 *
 * @framework ggLowCodeGTMKit
 */
const max = function(numberArray, additionalNumbers) {
    const additional = additionalNumbers || [];
    const combined = additional.length > 0 
        ? numberArray.concat(additional)
        : numberArray;
    const validNumbers = combined.filter(arg => typeof arg === 'number' && arg === arg);
    
    if (validNumbers.length === 0) return 0/0; // NaN
    
    let result = validNumbers[0];
    for (let i = 1; i < validNumbers.length; i++) {
        if (validNumbers[i] > result) {
            result = validNumbers[i];
        }
    }
    return result;
};
const safeFunction = fn => typeof fn === 'function' ? fn : x => x;
const out = safeFunction(data.out);
// ===============================================================================
// max - Direct mode
// ===============================================================================
const extractArgumentValues = (items) => items.map(item => item ? item.arg : null);
const applyCast = (castFn, value) => safeFunction(castFn)(value);
const extractedValues = extractArgumentValues(data.src);
const value = applyCast(data.pre, extractedValues);
return out(max(value));
// ===============================================================================
// max(...) – Apply Mode
// ===============================================================================
/*
return function(numberArray) {
   const extractAdditionalValues = (items) => items ? items.map(item => item ? item.arg : null) : [];
   const additionalNumbers = extractAdditionalValues(data.add);
   return out(max(numberArray, additionalNumbers));
};
*/

🧪 View Test Scenarios (5 tests)

✅ '[example] Maximum of positive numbers'
✅ Test finding maximum with additional numbers (Apply Mode only feature)
✅ Test with ceiling value
✅ '[example] Maximum with negatives'
✅ Test with single number