## Scorpio News |
## January–March 1987 – Volume 1. Issue 1. |

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100 FORMAT(9HDATA FROM,/,10HEXPERIMENT,I3)

which would print out

DATA FROM EXPERIMENT 1 (assuming that L had a value of 1)

F80 and ProFortran recognise ten different types of I/O field descriptor:

A | Alphanumeric [A – Z, 0 – 9 etc.] |

D | Double precision numeric |

E | Exponent form [e.g. 1.1E04 = 11,000] |

F | Floating point [e.g. 12.34) |

G | (can be used for floating point or exponent) |

H | Hollerith (string) |

(or) ' | alternative to Hollerith |

I | Integer data [e.g. 12, 560) |

L | Logical [T(rue) c F(alse)] – not often used. |

P | optional scaling descriptor used with D,E,F and G conversions either as a multiple or a fraction |

X | blank space |

These are fairly standard for most FORTRANs but NFortran does not have Double Precision or the scaling descriptor P. It does have T (tabulation), K (hexadecimal) and Z (inhibit <cr,lf> on output) which might be useful.

Most users will only be concerned with A,E,F,H,I and X descriptors; apart from the H and X descriptors, which have the general forms nH or nX where n is the number of columns each descriptor covers, the rest have the operational form rZy where r is the number of repetitions of the field descriptor if this it grater than 1, Z is the descriptor type and y giver information about the total width of field required for each repetition.

Some examples would not come amiss here –

10A4 | indicates 10 alphanumeric fields each 4 columns wide |

E8.2 | indicates 1 exponent field 8 columns wide, where there are two figures after the decimal point. Thus 12345.67 is represented as 0.12E¯05 (where the ‘¯’ represents a blank column in which nothing is printed) |

E12.5 | is a single exponent field of 12 columns in which 5 figures follow the decimal point and a figure such as −12.345678 would be represented as −0.12345E¯02. This implies that the number is truncated (shortened) and loses some accuracy. |

F3.0 | shows that a floating point number occupying 3 columns is involved which has no significant numbers to the right of the decinal point, 7.0 er 2.0 would be shown in this way |

F8.4 | shows that the floating point (real) number occupies 6 columns and has 4 digits to the right of the decimal point. 123.4567 is a suitable example: a real number such as −34.89088 would be shown as 34.8909, since the field only permits a maximum of 4 digits after the decimal point. Overflow can occur if the number of digits to the left of the decimal point cannot be fitted into the space available – thus 1234.56 would be printed as *.56 – the asterisk shows that the field width was too small. |

4I3 | indicates that there are four 3 digit integer fields involved; thus 123, 245, 778 and 200 are represented as: 123245778200 while −30, 2, 45 and 559 are represented by −30¯¯2¯45559. In the latter case, the ‘–’ sign occupies 1 of the columns in its field and the numbers with less than 3 digits are right justified |

4X | this shows that 4 columns are to be skipped (not read or printed) |

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