10.7: Character Format Specifier

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The character format specifier rAw is used tell the system exactly how many positions should be used to either read or write a character variable. The w is the width or how many total places are used. If the width is not specified, the existing length of the string is used. The r is the number of times the format specifier should be repeated.

A format of '(a6)' would look like:

c	c	c	c	c	c
\(\leftarrow \quad\) w \(\quad \rightarrow\)

For example, given the declarations,

character(len=11) :: msg = "Hello World"

the following write statement can be used to display the string in variable msg with no leading or trailing spaces. The following write statement,

write (*,'(a11)') msg

will display “Hello World”. The count is not required when using the character format specifier. For example, the statement,

write (*,'(a)') msg

will display the same “Hello World” string. Multiple variables or strings can be displayed. Also, the count can be used to display a portion of the string. For example, to display the string in variable msg and the string “Goodbye cruel world”.

write (*,'(a9,2x,a)') msg, "Goodbye cruel world"

Which will display “Hello Wor Goodbye cruel world” to the screen. Note that for the first string variable, msg, only the first 9 characters of the 11 total characters are displayed since the A9 format was used.