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Conversione del tipo di dati

Convertire tra array numerici, stringhe e array di caratteri, date e orari, array di celle, strutture o tabelle

MATLAB^® dispone di molte funzioni per convertire i valori da un tipo di dati a un altro per utilizzarli in contesti diversi. Ad esempio, è possibile convertire i numeri in testo e quindi aggiungerli alle etichette del grafico o ai nomi dei file. I numeri possono essere rappresentati come valori esadecimali o binari. MATLAB fornisce le funzioni per la conversione tra array numerici, stringhe e array di caratteri e array categorical, datetime e duration. È inoltre possibile effettuare conversioni tra i tipi di dati che raggruppano i dati in contenitori, come gli array di celle, le strutture, le tabelle e gli orari. In questi casi, i valori dei dati rimangono gli stessi, ma vengono memorizzati e consultati in un tipo di contenitore diverso.

Funzioni

espandi tutto

Numeri e testo

Conversione di numeri in testo

`string`	String array
`char`	Character array
`cellstr`	Convert to cell array of character vectors
`int2str`	Convertire i numeri interi in caratteri
`mat2str`	Convert matrix to characters
`num2str`	Convert numbers to character array

Conversione di testo in numeri

`str2double`	Convert strings to double precision values
`str2num`	Convert character array or string to numeric array
`native2unicode`	Convert numeric bytes to Unicode character representation
`unicode2native`	Convert Unicode character representation to numeric bytes

Numeri esadecimali e binari

`base2dec`	Convert text representation of base-`n` integer to double value
`bin2dec`	Convert text representation of binary integer to double value
`dec2base`	Convert decimal integer to its base-`n` representation
`dec2bin`	Convert decimal integer to its binary representation
`dec2hex`	Convert decimal integer to its hexadecimal representation
`hex2dec`	Convert text representation of hexadecimal integer to double value
`hex2num`	Convert IEEE hexadecimal format to double-precision number
`num2hex`	Convert single- and double-precision numbers to IEEE hexadecimal format

Date e orari

Conversione dei valori in date e orari

`datetime`	Arrays that represent points in time
`duration`	Lengths of time in fixed-length units
`matlab.datetime.compatibility.convertDatenum`	Convert inputs to `datetime` values in a backward-compatible way (Da R2022a)

Conversione delle date e degli orari in testo

`string`	String array
`char`	Character array
`cellstr`	Convert to cell array of character vectors

Array categorici, tabelle e orari

Array categorici

categorical Array that contains values assigned to categories

Tabelle

`table2array`	Convertire la tabella in array omogeneo
`table2cell`	Convert table to cell array
`table2struct`	Convert table to structure array
`array2table`	Convert homogeneous array to table
`cell2table`	Convert cell array to table
`struct2table`	Convert structure array to table

Orari

`array2timetable`	Convert homogeneous array to timetable
`table2timetable`	Convert table to timetable
`timetable2table`	Convert timetable to table

Array di celle e strutture

`cell2mat`	Convertire l'array di celle in un array ordinario del tipo di dati sottostante
`cell2struct`	Convert cell array to structure array
`mat2cell`	Convert array to cell array whose cells contain subarrays
`num2cell`	Convert array to cell array with consistently sized cells
`struct2cell`	Convert structure to cell array

Argomenti

Convert Text to Numeric Values
Convert text to arrays of numeric values. Text can represent floating-point values, dates and times, and hexadecimal and binary numbers. If text represents dates and times, then you can convert the text to datetime or duration values.
Convert Numeric Values to Text
Convert numeric values to text. Text can represent floating-point values, either with or without exponential notation, or hexadecimal or binary digits. Use these conversions to add numbers to text such as plot labels or titles.
Unicode and ASCII Values
MATLAB stores all characters as Unicode characters. Both strings and character vectors use the same encoding. You can convert characters to their Unicode code values, and numbers to characters.
Hexadecimal and Binary Values
Specify hexadecimal and binary values either as literals or as text. Hexadecimal and binary literals are stored as integers. You can convert text representing hexadecimal and binary values to numbers, and numbers to text representations.
Convert Between Text and datetime or duration Values
The datetime and duration data types are the recommended data types for working with dates and times. You can convert these data types to text by using the string function, and you can convert text to these data types by using the datetime and duration functions. When you read text representing dates and times from spreadsheets and text files you can automatically convert the text to datetime or duration arrays.
Convert Text in Table Variables to Categorical
This example shows how to convert a variable in a table from a cell array of character vectors to a categorical array.
Valid Combinations of Unlike Classes
If you include elements of unlike classes in a matrix, MATLAB converts some elements so that all elements of the resulting matrix are of the same type. Data type conversion is done with respect to a preset precedence of classes.