Input/Output

FORTRAN-SO

'E' Descriptor Editing

An I/O list item matched with an 'Ew.d' or 'Ew.dEe' descriptor must be a real variable. The exponent 'e' has no effect on input data.

On output, the format of the output field for a scale factor (section 6.4.3.1.2) of zero is:

[±][0].x1 x2··· x d exP

where

 

 

 

 

±

signifies a plus or minus

 

 

 

 

 

are the 'd' most significant digits of the data's value

 

 

after rounding

 

 

 

 

exp

is a decimal exponent having one of the following forms

 

 

('y' is a digit):

 

 

 

 

 

 

 

 

 

Edit Descriptor

Absolute value of 'exp'

Form of 'exp'

 

 

 

 

 

 

 

 

Ew.d

lexpl:$ 99

±

OY1 Y2

 

 

99< lexpl:$ 999

 

 

 

 

 

±

Y1 Y2 Y3

 

 

Ew.dEe

lexpl:$(10**e)-1

E ± Y1 Y2···Ye

 

 

 

 

 

 

 

The sign in the exponent is always present. If the exponent is zero, it is prefixed by a plus. The 'Ew.d' descriptor should not be used if exp exceeds 999.

Decimal normalization is controlled by the scale factor 'k' (section 6.4.3.1.2). If -d<k:$O,the number output will have exactly Iklleading zeros and 'd - Ikl' significant digits following the decimal point. If 0< k< d + 2, the number will have exactly k significant digits to the left of the decimal point and 'd - k + 1, signifi- cant digits to the right of the decimal point. Other values of k are not legal.

Examples:

READ (2,30) RLNUMB

30 FORMAT (E4.2)

WRITE (6,110) RLOUT

110 FORMAT (E6.5E6)

Logical Editing

An I/O item matched with an 'Lw' descriptor must be of type logical.

The input field includes an optional period followed by a 'T' (for TRUE) or 'F' (for FALSE). These characters may be followed by additional characters. For example, the logical constants' .TRUE.' and' .FALSE.' are acceptable inputs.

The output field consists of the letters 'T' or 'F,' based on the TRUE or FALSE value of the internal data.

Examples:

DIMENSION TRUTH(4)

READ (3,50) TRUTH(1), TRUTH(4)

50 FORMAT (2L6)

WRITE (6,80) TRUTH(1)

80 FORMAT (L1)

6-18

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Image 78
Intel fortran-80 manual OY1 Y2, Y1 Y2 Y3, ± Y1 Y2···Ye