10.3: Integer Format Specifier

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The integer format specifier rIw or rIw.m is used tell the system exactly how many positions should be used to either read or write an integer variable. The w is the width or how many total places are used. If the number is negative, the sign uses a place. The m is optional and can be used to set a minimum number of digits to display, which will display leading zeros if needed in order to display the minimum number of digits. The r is the number of times the format specifier should be repeated.

A format of '(i6)' would look like:

x	x	x	x	x	x
\(\leftarrow \quad \) w \(\quad \rightarrow\)

For example, given the declarations,

integer :: num1=42, num2=123, num3=4567

the following write statement can be used to display the value in variable num1 with no leading or trailing spaces.

write (*,'(i2)') num1

Which will display “42”.

Multiple variables can be displayed. For example, to display the values in variables num1 and num2, with no leading or trailing spaces.

write (*,'(i2,i3)') num1, num2

Which will display “42123” with no spaces between the two different values. However,

write (*,'(i2,i4)') num1, num2

will display “42 123” with one space between the values. Further,

write (*,'(i5,i5,i5)') num1, num2, num3

will display “ 42 123 4567” where each variable uses 5 spaces. And, finally,

write (*,'(i6.4)') num1

will display “ 0042”.