Convert Numeric Values to Text
This example shows how to convert numeric values to text and append them to larger pieces of text.
For example, you might want to add a label or title to a plot, where the label includes a number that
describes a characteristic of the plot.
Convert to Strings
Before R2016b, convert to character vectors using num2str.
To convert a number to a string that represents it, use the string function.
str = string(pi)
str =
"3.1416"
The string function converts a numeric array to a string array having the same size.
A = [256 pi 8.9e-3];
str = string(A)
str = 1x3 string
"256"
"3.141593"
"0.0089"
You can specify the format of the output text using the compose function, which accepts format
specifiers for precision, field width, and exponential notation.
str = compose("%9.7f",pi)
str =
"3.1415927"
If the input is a numeric array, then compose returns a string array. Return a string array that
represents numbers using exponential notation.
A = [256 pi 8.9e-3];
str = compose("%5.2e",A)
str = 1x3 string
"2.56e+02"
"3.14e+00"
"8.90e-03"
Add Numbers to Strings
Before R2016b, convert numbers to character vectors and concatenate characters in brackets, [].
The simplest way to combine text and numbers is to use the plus operator (+). This operator
automatically converts numeric values to strings when the other operands are strings.
For example, plot a sine wave. Calculate the frequency of the wave and add a string representing that
value in the title of the plot.
X = linspace(0,2*pi);
Y = sin(X);
plot(X,Y)
Convert Numeric Values to Text
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