Fortran 简明教程

Fortran - Programming Style

编程风格涉及的是在开发程序时遵循一些规则。这些良好的做法会给您的程序带来可读性、明确性等价值。

Programming style is all about following some rules while developing programs. These good practices impart values like readability, and unambiguity into your program.

一个好的程序应具备以下特点：

A good program should have the following characteristics −

  1. Readability

  2. Proper logical structure

  3. Self-explanatory notes and comments

例如，如果您做出如下评论，则不会有太大帮助：

For example, if you make a comment like the following, it will not be of much help −

! loop from 1 to 10
do i = 1,10

然而，如果您正在计算二项式系数，并且需要这个循环求 nCr，那么这样的注释会有帮助：

However, if you are calculating binomial coefficient, and need this loop for nCr then a comment like this will be helpful −

! loop to calculate nCr
do i = 1,10

  1. Indented code blocks to make various levels of code clear.

  2. Self-checking codes to ensure there will be no numerical errors like division by zero, square root of a negative real number or logarithm of a negative real number.

  3. Including codes that ensure variables do not take illegal or out of range values, i.e., input validation.

  4. Not putting checks where it would be unnecessary and slows down the execution. For example −

real :: x
x = sin(y) + 1.0

if (x >= 0.0) then
   z = sqrt(x)
end if

  1. Clearly written code using appropriate algorithms.

  2. Splitting the long expressions using the continuation marker ‘&’.

  3. Making meaningful variable names.