Difference between revisions of "Datatype functions"

Revision as of 08:32, 16 November 2015

Analytica User GuideUsing ExpressionsDatatype functions

A value can be a number, text, Null, or a reference. Integers, reals, Boolean, and date values, are all represented as numbers. You can use these functions from the Special library of Definition menu to determine the type.

'IsNumber(x)': Returns True if x is a number, including a boolean, date, INF, NAN, or complex.

IsNumber(0) → True

IsNumber(False) → True

IsNumber(INF) → True

IsNumber('hi') → False

IsNumber(5) → True

IsNumber('5') → False

IsNumber(NAN) → True

IsText(x): Returns True if x is a text value.

IsText('hello') → True

IsText(7) → False

IsText('7') → True

IsNaN(x): Returns True if x is “not a number,” i.e., NAN. INF or regular numbers do not qualify, nor does a text or Null.

0/0 → NAN

IsNaN(0/0) → True

IsNaN(5) → False

IsNaN(INF) → False

IsNaN('Hello') → False

IsNull(x): To test if x is exactly Null. Returns false if x is an array.

x = NULL: To test if an atomic x is Null. When x is an array, returns True or False for each element of the array.

IsUndef(x): Returns True if atomic x is Nullor the internal value Undefined (usually indicating uncomputed). When x is an array, returns True or False for each element of the array.

IsRealNumber(x): Returns True when x is a real number, including a boolean, date or INF. Returns False when x is a complex number or NAN.

IsReference(x): Returns True if x is a reference to a value.

IsHandle(x): Returns True if x is a handle to an Analytica object.

TypeOf(x): Returns the type of expression x as a text value, usually one of Number, Text, Reference, or Null. INF and NAN are both of type "Number":

TypeOf(2008) → "Number"

TypeOf('2008') → "Text"

TypeOf(INF) → "Number"

TypeOf(0/0) → "Number"

@@ Line 5: / Line 5: @@
 A value can be a number, text, <code>Null</code>, or a reference. Integers, reals, Boolean, and date values, are all represented as numbers. You can use these functions from the '''Special '''library of '''Definition '''menu to determine the type.
-'''IsNumber(x)''': Returns <code>True</code> if <code>x</code> is a number, including a boolean, date, <code>INF</code>, <code>NAN</code>, or complex.
+''[['IsNumber]](x)''': Returns <code>True</code> if <code>x</code> is a number, including a boolean, date, <code>INF</code>, <code>NAN</code>, or complex.
 :<code>IsNumber(0) &rarr; True </code>
 :<code>IsNumber(False) &rarr; True </code>
@@ Line 14: / Line 14: @@
 :<code>IsNumber(NAN) &rarr; True</code>
-'''IsText(x)''': Returns <code>True</code> if <code>x</code> is a text value.
+'''[[IsText]](x)''': Returns <code>True</code> if <code>x</code> is a text value.
 :<code>IsText('hello') &rarr; True </code>
 :<code>IsText(7) &rarr; False</code>
 :<code>IsText('7') &rarr; True</code>
-'''IsNaN(x)''': Returns <code>True</code> if <code>x</code> is “not a number,” i.e., <code>NAN</code>. <code>INF</code> or regular numbers do not qualify, nor does a text or <code>Null</code>.
+'''[[IsNaN]](x)''': Returns <code>True</code> if <code>x</code> is “not a number,” i.e., <code>NAN</code>. <code>INF</code> or regular numbers do not qualify, nor does a text or <code>Null</code>.
 :<code>0/0 &rarr; NAN</code>
 :<code>IsNaN(0/0) &rarr; True </code>
@@ Line 26: / Line 26: @@
 :<code>IsNaN('Hello') &rarr; False</code>
-'''IsNull(x)''': To test if <code>x</code> is exactly <code>Null</code>. Returns false if <code>x</code> is an array.
+'''[[IsNull]](x)''': To test if <code>x</code> is exactly <code>Null</code>. Returns false if <code>x</code> is an array.
 '''x <nowiki>=</nowiki> NULL''': To test if an atomic <code>x</code> is <code>Null</code>. When <code>x</code> is an array, returns <code>True</code> or <code>False</code> for each element of the array.
-'''IsUndef(x)''': Returns <code>True</code> if atomic <code>x</code> is <code>Null</code>or the internal value '''Undefined '''(usually indicating uncomputed). When <code>x</code> is an array, returns <code>True</code> or <code>False</code> for each element of the array.
+'''[[IsUndef]](x)''': Returns <code>True</code> if atomic <code>x</code> is <code>Null</code>or the internal value '''Undefined '''(usually indicating uncomputed). When <code>x</code> is an array, returns <code>True</code> or <code>False</code> for each element of the array.
-'''IsRealNumber(x)''': Returns <code>True</code> when <code>x</code> is a real number, including a boolean, date or <code>INF</code>. Returns <code>False</code> when <code>x</code> is a complex number or <code>NAN</code>.
+'''[[IsRealNumber]](x)''': Returns <code>True</code> when <code>x</code> is a real number, including a boolean, date or <code>INF</code>. Returns <code>False</code> when <code>x</code> is a complex number or <code>NAN</code>.
-'''IsReference(x)''': Returns <code>True</code> if <code>x</code> is a reference to a value.
+'''[[IsReference]](x)''': Returns <code>True</code> if <code>x</code> is a reference to a value.
-'''IsHandle(x)''': Returns <code>True</code> if <code>x</code> is a handle to an Analytica object.
+'''[[IsHandle]](x)''': Returns <code>True</code> if <code>x</code> is a handle to an Analytica object.
-'''TypeOf(x)''': Returns the type of expression <code>x</code> as a text value, usually one of <code>Number, Text, Reference, or Null</code>. <code>INF</code> and <code>NAN</code> are both of type <code>"Number"</code>:
+'''[[TypeOf]](x)''': Returns the type of expression <code>x</code> as a text value, usually one of <code>Number, Text, Reference, or Null</code>. <code>INF</code> and <code>NAN</code> are both of type <code>"Number"</code>:
 :<code>TypeOf(2008) &rarr; "Number" </code>
 :<code>TypeOf('2008') &rarr; "Text" </code>

Difference between revisions of "Datatype functions"

Revision as of 08:32, 16 November 2015

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