And, for the first element in our cell array I'm going to create a vector. I'm going to call it, my cell and instead of creating it with parentheses or square brackets, we're going to create this with curly brackets. So, let's just go ahead and create one to see how it works. But, each element in that matrix can be a different data type. So you can think of a cell array like a matrix. Let's go ahead and clear the screen and I'm going to clear the workspace while we're at it. I found these really, really useful in my work so I wanted to show them to you here. And, MATLAB allows us to do that with cell arrays. Much of what was said about indexing matrices also applies to cells with one or two important differences.- Often, if we're working with complicated data sets, we want to be able to associate different data types, like say, vectors and strings together in a single construct. char arrays of different sizes), which is why we discuss them here. Cell arrays are frequently used to store strings, (i.e. In fact, the same cell array can hold elements of different types. Cell arrays can hold any type of Matlab object or structure including numeric matrices of different sizes, character arrays, other cells, as well as structs and objects, which we will see later. In addition to matrices, Matlab supports another very general and powerful data structure, the cell array. Kosuke Kitajima won the gold medal in the 100m breaststroke Str = sprintf( '%x',999) % display number in hexadecimal Str = sprintf( '%07.4f',pi) % display pi to 4 decimals, 7 chars in total, padded with zeros.
Creating a cell array matlab code#
'Kosuke Kitajima', 'gold', '100m breaststroke',60.08) Code a cell array by listing a series of numbers, vectors, or characters in the same format as a matrix while characters are in quotation marks and vectors are. fprintf( '\n %s won the %s medal in the %s \n for his time of %05.2f seconds.\n'. We can use escape characters like \n for a new line and \t for a tab.
Creating a cell array matlab full#
There are many formatting options Type doc sprintf for the full list. We use %s for a string, %d for a decimal digit, and %05.2f to indicate that we want a floating point number with 5 characters in total, two digits after the decimal point, and padded with zeros if necessary. These place holders define how these values will be formatted. We pass these functions a string that includes place holders, (denoted by % signs) which will be replaced by corresponding values listed after the string. The sprintf() and fprintf() functions can be used to format strings for output: sprintf() returns a string, while fprintf() directly displays the string, or writes it to a file, depending on the mode. C = strvcat( 'hello', 'this', 'is', 'a', 'test') %concatenate verticallyĭ = sortrows(C) % sort the rows alphabetically D =Į = strjust(C) % justify the char array E = If not, we can either use the blanks() function to pad with blanks or the strcat() and strvcat() functions to concatenate, adding blanks for us. If the size of the strings match, we can concatenate vertically and horizontally just like numeric matrices. Or, parse a number from a string with str2num() A = num2str() %Takes an optional formatting string - see Formatting Strings section We can also use the num2str() and mat2str() functions to generate string representations of numeric matrices. The num2xxx and xxx2num functions operate on signed numbers. We can convert from string representations of hexadecimal or binary numbers to decimal numbers and back using the dec2hex(), hex2dec(), dec2bin(), and bin2dec() functions. The char() and abs() functions convert from integers to the ascii equivalents and vice versa. str = ' a1!'Ī = isstrprop(str, 'punct') % punctuationī = isstrprop(str, 'alphanum') % alpha or numeric charactersĬ = isstrprop(str, 'digit') % decimal digitsĭ = isstrprop( '3A', 'xdigit') % valid hexadecimal digits str = The isstrprop() function can be used much like the isletter() or isspace() functions, allowing you to test which characters in a matrix belong to one of several different categories. K = deblank(A) % trim trailing blank spaces only. J = strtrim(A) % trim leading and trailing blank spaces.
G = isspace(A(1:6)) % which characters are spaces? - returns a logical array
A = ' This is Test String #1! 'ī = A(1:5) % extract the first 5 charactersĭ = repmat( % replicate char arrays, just like numeric onesĮ = 'z':-1: 'a' % create the matrices just like numeric ones.į = isletter(A(1:6)) % which characters are letters? - returns a logical array Strings in Matlab are actually character matrices, which can be manipulated in very similar ways to numeric matrices.
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