Rounding Figures in X++

X++ provides built-in functions that round numerical values based on specific conditions. These functions allow developers to round numbers to a defined decimal place or to the nearest multiple of a specified value.

Common Rounding Functions in X++

The following rounding functions are available in X++:

• round – Rounds a number to the nearest multiple of a given value.

• decround – Rounds a number to a specified number of decimal places.

• roundzero – Rounds a number toward zero.

• rounddown – It always rounds a number down.

• roundup – It always rounds a number up.

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Using the round Function

The round function rounds a number to the nearest multiple of the second argument.

Example:

round(1.2, 1);    // Output: 1  
round(1.2, 5);    // Output: 0  
round(6.4, 5);    // Output: 5  
round(7.5, 5);    // Output: 10  
round(1.2, 0.5);  // Output: 1  
round(1.12, 0.1); // Output: 1.1

📌 Key takeaway: The round function rounds to the closest multiple of the second argument. If the value is exactly in the middle (For instance., 7.5 rounding to 5), it rounds up to the nearest multiple.

Using the decround Function

The decround function rounds a number to a specified number of decimal places.

Example:

decround(1.2, 0);   // Output: 1  
decround(1.23, 0);  // Output: 1  
decround(1.23, 1);  // Output: 1.2  
decround(1.25, 1);  // Output: 1.3

📌 Key takeaway: The decround function is used when rounding is required at a specific decimal precision. It follows standard rounding rules where values >= 5 round up, and values < 5 round down.

Practical Use Case

A commonly used rounding method which aligns with what we were taught in schools, if the decimal value is 5 or greater, the number is rounded up; else, it is rounded down.

Example:

Amount amountCurDebit = 4056.65;  
Amount amountCurCredit = 768.30;  

// Applying decround  
decround(amountCurDebit, 0);  // Output: 4057.00  
decround(amountCurCredit, 0); // Output: 768.00

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Using the roundup Function

The roundup function always rounds a number up to the nearest multiple of the specified value, even if the number is already close to the next multiple.

Example:

roundup(1.2, 1);   // Output: 2  
roundup(1.2, 5);   // Output: 5  
roundup(6.4, 5);   // Output: 10  
roundup(7.5, 5);   // Output: 10  
roundup(1.2, 0.5); // Output: 1.5  
roundup(1.12, 0.1); // Output: 1.2

📌 Key takeaway: roundup ensures that the value always increases, it never decreases.

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Using the rounddown Function

The rounddown function always rounds a number down to the nearest multiple of the specified value, ensuring that values always decreases after rounding.

Example:

rounddown(1.8, 1);   // Output: 1  
rounddown(1.8, 5);   // Output: 0  
rounddown(6.4, 5);   // Output: 5  
rounddown(7.5, 5);   // Output: 5  
rounddown(1.8, 0.5); // Output: 1.5  
rounddown(1.88, 0.1); // Output: 1.8

📌 Key takeaway: rounddown ensures that the value always decrease and never increases.

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A Practical Use Case

When working with inventory management or financial transactions, there are scenarios where rounding up or rounding down is necessary. For example:

• Rounding up is useful when calculating minimum order quantities.

• Rounding down is useful when dealing with inventory levels to avoid exceeding available stock.

Example:

Amount orderQty = 2.3;  
Amount availableStock = 9.7;  

// Order quantity is always a whole number  
roundup(orderQty, 1);  // Output: 3  
rounddown(availableStock, 1); // Output: 9

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Conclusion

The choice of the rounding method differs based on the requirement. In this article, we’ve reviewed the common rounding methods with multiple scenarios of their application and expected output.

See Also

https://learn.microsoft.com/en-us/previous-versions/dynamics/ax-2012/reference/aa499511(v=ax.60)

https://learn.microsoft.com/en-us/previous-versions/dynamics/ax-2012/reference/aa850656(v=ax.60)?redirectedfrom=MSDN

https://d365ffo.com/2021/07/30/ax-d365fo-round-up-or-round-down-a-number-to-the-next-whole-number/