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# QDoubleValidator Class Reference
[QtGui module]

The QDoubleValidator class provides range checking of floating-point numbers. More...

Inherits QValidator.

### Types

- enum Notation { StandardNotation, ScientificNotation }

### Methods

- __init__ (self, QObject)
- __init__ (self, float, float, int, QObject)
- float bottom (self)
- int decimals (self)
- Notation notation (self)
- setBottom (self, float)
- setDecimals (self, int)
- setNotation (self, Notation)
- setRange (self, float, float, int decimals = 0)
- setTop (self, float)
- float top (self)
- (QValidator.State, QString, int) validate (self, QString, int)
- (QValidator.State, int) validate (self, QString, int)

## Detailed Description

The QDoubleValidator class provides range checking of floating-point numbers.

QDoubleValidator provides an upper bound, a lower bound, and a limit on the number of digits after the decimal point. It does not provide a fixup() function.

You can set the acceptable range in one call with setRange(), or with setBottom() and setTop(). Set the number of decimal places with setDecimals(). The validate() function returns the validation state.

QDoubleValidator uses its locale() to interpret the number. For example, in the German locale, "1,234" will be accepted as the fractional number 1.234. In Arabic locales, QDoubleValidator will accept Arabic digits.

In addition, QDoubleValidator is always guaranteed to accept a number formatted according to the "C" locale. QDoubleValidator will not accept numbers with thousand-seperators.

See also QIntValidator, QRegExpValidator, and Line Edits Example.

## Type Documentation

### QDoubleValidator.Notation

This enum defines the allowed notations for entering a double.

Constant | Value | Description
--- | --- | ---
`QDoubleValidator.StandardNotation` | `0` | The string is written as a standard number (i.e. 0.015).
`QDoubleValidator.ScientificNotation` | `1` | The string is written in scientific form. It may have an exponent part(i.e. 1.5E-2).

This enum was introduced in Qt 4.3.

## Method Documentation

### QDoubleValidator.__init__ (self, QObject)

The QObject argument, if not None, causes self to be owned by Qt instead of PyQt.

Constructs a validator object with a parent object that accepts any double.

### QDoubleValidator.__init__ (self, float, float, int, QObject)

The QObject argument, if not None, causes self to be owned by Qt instead of PyQt.

Constructs a validator object with a parent object. This validator will accept doubles from bottom to top inclusive, with up to decimals digits after the decimal point.

### float QDoubleValidator.bottom (self)

### int QDoubleValidator.decimals (self)

### Notation QDoubleValidator.notation (self)

### QDoubleValidator.setBottom (self, float)

### QDoubleValidator.setDecimals (self, int)

### QDoubleValidator.setNotation (self, Notation)

### QDoubleValidator.setRange (self, float, float, int decimals = 0)

Sets the validator to accept doubles from minimum to maximum inclusive, with at most decimals digits after the decimal point.

### QDoubleValidator.setTop (self, float)

### float QDoubleValidator.top (self)

### (QValidator.State, QString, int) QDoubleValidator.validate (self, QString, int)

Reimplemented from QValidator.validate().

Returns Acceptable if the string input contains a double that is within the valid range and is in the correct format.

Returns Intermediate if input contains a double that is outside the range or is in the wrong format; e.g. with too many digits after the decimal point or is empty.

Returns Invalid if the input is not a double.

Note: If the valid range consists of just positive doubles (e.g. 0.0 to 100.0) and input is a negative double then Invalid is returned. If notation() is set to StandardNotation, and the input contains more digits before the decimal point than a double in the valid range may have, Invalid is returned. If notation() is ScientificNotation, and the input is not in the valid range, Intermediate is returned. The value may yet become valid by changing the exponent.

By default, the pos parameter is not used by this validator.

### (QValidator.State, int) QDoubleValidator.validate (self, QString, int)