BcMath\Number
PHP Manual

BcMath\Number::sqrt

Gets the square root of an arbitrary precision number

Description

public BcMath\Number BcMath\Number::sqrt(intnull $scale = null)

Return the square root of $this.

Parameters

scale
BcMath\Number::scale explicitly specified for calculation results. If null, the BcMath\Number::scale of the calculation result will be set automatically.

Return Values

Returns the square root as a new BcMath\Number object.

When the BcMath\Number::scale of the result object is automatically set, the BcMath\Number::scale of $this is used. However, in cases such as indivisible division, the BcMath\Number::scale of the result is expanded. Expansion is done only as needed, up to a maximum of +10. This behavior is the same as BcMath\Number::div, so please see that for details.

That is, if the BcMath\Number::scale of $this is 5, the BcMath\Number::scale of the result is between 5 and 15.

Errors/Exceptions

This method throws a ValueError in the following cases:

  • $this is a negative value
  • scale is outside the valid range
  • BcMath\Number::scale of the result object is outside the valid range

Examples

Example #1 BcMath\Number::sqrt example

<?php
var_dump(
    new BcMath\Number('2')->sqrt(),
    new BcMath\Number('2')->sqrt(3),
    new BcMath\Number('4')->sqrt(),
    new BcMath\Number('4')->sqrt(3),
);
?>

The above example will output:

object(BcMath\Number)#2 (2) {
  ["value"]=>
  string(12) "1.4142135623"
  ["scale"]=>
  int(10)
}
object(BcMath\Number)#3 (2) {
  ["value"]=>
  string(5) "1.414"
  ["scale"]=>
  int(3)
}
object(BcMath\Number)#4 (2) {
  ["value"]=>
  string(1) "2"
  ["scale"]=>
  int(0)
}
object(BcMath\Number)#5 (2) {
  ["value"]=>
  string(5) "2.000"
  ["scale"]=>
  int(3)
}

See Also

  • bcsqrt
  • BcMath\Number::div
  • BcMath\Number::pow