| Description |
The Sqrt function returns the square root of a Number.
The number must be a floating point type.
Special values are treated as follows:
| Infinity | : Infinity |
| -0 | : -0 |
| NaN (Not a Number) | : NaN |
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| Notes |
Warning : the square root of a negative number is an imaginary number. In Delphi, use the Math routines to handle these.
Sqrt should raise an EInvalidOp exception when the Number is negative. In practice, the author's PC crashed (running Windows ME) when attempted.
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| Related commands |
| Sqr |
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Gives the square of a number |
| Sum |
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Return the sum of an array of floating point values |
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| Example code : Find the square root of various values |
// Full Unit code.
// -----------------------------------------------------------
// You must store this code in a unit called Unit1 with a form
// called Form1 that has an OnCreate event called FormCreate.
unit Unit1;
interface
uses
// The System unit does not need to be defined
Math,
Forms, Dialogs;
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm} // Include form definitions
procedure TForm1.FormCreate(Sender: TObject);
var
number, squareRoot : Extended;
begin
// The square root of 225 = 15
number := 225;
squareRoot := Sqrt(number);
ShowMessageFmt('Square root of %f = %f',[number, squareRoot]);
// The square root of 3.456 = 1.859...
number := 3.456;
squareRoot := Sqrt(number);
ShowMessageFmt('Square root of %7.3f = %12.12f',[number, squareRoot]);
// The square root of infinity is still infinity
number := Infinity;
number := Sqrt(number);
ShowMessageFmt('Square root of Infinity = %f',[number]);
end;
end.
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| Hide full unit code |
Square root of 225.0 = 15.0
Square root of 3.456 = 1.859032006180
Square root of Infinity = INF
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