sec2-2.htm

Fortran,骨灰级的语言

<p class=MsoNormal align=center style='margin-top:15.6pt;margin-right:0cm;
margin-bottom:15.6pt;margin-left:0cm;mso-para-margin-top:1.0gd;mso-para-margin-right:
0cm;mso-para-margin-bottom:1.0gd;mso-para-margin-left:0cm;text-align:center;
tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt'><a
name="第2_2_2"><span lang=EN-US style='font-size:16.0pt;mso-bidi-font-size:12.0pt;
mso-fareast-font-family:楷体_GB2312'>2.2.2</span></a><span style='mso-bookmark:
第2_2_2'></span><span lang=ZH-CN style='font-size:16.0pt;mso-bidi-font-size:
12.0pt;font-family:楷体_GB2312;mso-ascii-font-family:"Times New Roman";
color:red'>逻辑表达式</span><b><span lang=EN-US style='font-size:16.0pt;mso-bidi-font-size:
12.0pt;mso-fareast-font-family:楷体_GB2312'><o:p></o:p></span></b></p>

<p style='tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:10.5pt'><a name="第2_2_2a"><span lang=EN-US
style='font-family:宋体;color:red'>a)</span></a><span lang=EN-US
style='font-family:宋体;color:red'> </span><span lang=ZH-CN style='font-family:
宋体;color:red'>逻辑量</span><span lang=EN-US style='font-family:宋体;color:red'><o:p></o:p></span></p>

<p class=MsoNormal style='text-indent:24.0pt;mso-char-indent-count:2.0;
line-height:17.0pt;mso-line-height-rule:exactly;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:12pt'><span lang=EN-US style='font-size:12.0pt;font-family:
宋体'>Fortran</span><span lang=ZH-CN style='font-size:12.0pt;font-family:宋体'>的<span
style='color:fuchsia'>逻辑常量</span>只有两个：</span><span lang=EN-US style='font-size:
12.0pt;font-family:宋体'>.TRUE. (</span><span lang=ZH-CN style='font-size:12.0pt;
font-family:宋体'>表示“真”，即满足逻辑条件</span><span lang=EN-US style='font-size:12.0pt;
font-family:宋体'>)</span><span lang=ZH-CN style='font-size:12.0pt;font-family:
宋体'>；</span><span lang=EN-US style='font-size:12.0pt;font-family:宋体'> .FALSE. (</span><span
lang=ZH-CN style='font-size:12.0pt;font-family:宋体'>表示“假”，即不满足逻辑条件</span><span
lang=EN-US style='font-size:12.0pt;font-family:宋体'>)</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>。</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>

<p class=MsoNormal style='text-indent:24.0pt;mso-char-indent-count:2.0;
line-height:17.0pt;mso-line-height-rule:exactly;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:12pt'><span lang=ZH-CN style='font-size:12.0pt;font-family:
宋体'>例：当</span><span lang=EN-US style='font-size:12.0pt;font-family:宋体'>X=3</span><span
lang=ZH-CN style='font-size:12.0pt;font-family:宋体'>时，“</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'>X&lt;5</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>”的值为</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'>.TRUE.(</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>真</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'>)</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>，而“</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'>X&lt;=0.</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>”的值为</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'>.FALSE.(</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>假</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'>)</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>。</span><span lang=EN-US
style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>

<p class=MsoNormal style='text-indent:24.0pt;mso-char-indent-count:2.0;
line-height:17.0pt;mso-line-height-rule:exactly;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:12pt'><span lang=ZH-CN style='font-size:12.0pt;font-family:
宋体;color:fuchsia'>逻辑型变量</span><span lang=ZH-CN style='font-size:12.0pt;
font-family:宋体'>用来存放逻辑常量。它的值也只能是</span><span lang=EN-US style='font-size:12.0pt;
font-family:宋体'>.TRUE.</span><span lang=ZH-CN style='font-size:12.0pt;
font-family:宋体'>或</span><span lang=EN-US style='font-size:12.0pt;font-family:
宋体'>.FALSE.</span><span lang=ZH-CN style='font-size:12.0pt;font-family:宋体'>之一。可以将一逻辑常量赋予一个逻辑变量。如将</span><span
lang=EN-US style='font-size:12.0pt;font-family:宋体'>A</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>定义为逻辑型变量，用赋值语句对其赋值：</span><span
lang=EN-US style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>

<p class=MsoNormal style='margin-left:1.0cm;mso-para-margin-left:2.7gd;
text-indent:24.0pt;mso-char-indent-count:2.0;line-height:15.0pt;mso-line-height-rule:
exactly;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:12pt'><span lang=EN-US style='font-size:12.0pt;font-family:
宋体'>LOGICAL A<o:p></o:p></span></p>

<p class=MsoNormal style='margin-left:1.0cm;mso-para-margin-left:2.7gd;
text-indent:24.0pt;mso-char-indent-count:2.0;line-height:15.0pt;mso-line-height-rule:
exactly;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:12pt'><span lang=EN-US style='font-size:12.0pt;font-family:
宋体'>A=.TRUE.<o:p></o:p></span></p>

<p class=MsoNormal style='text-indent:24.0pt;mso-char-indent-count:2.0;
line-height:17.0pt;mso-line-height-rule:exactly;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:12pt'><span lang=ZH-CN style='font-size:12.0pt;font-family:
宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"'>逻辑赋值语句的一般形式为：<span
style='color:#FF9900'>逻辑变量＝逻辑表达式</span>。</span><span lang=EN-US
style='font-size:12.0pt'><o:p></o:p></span></p>

<p style='tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt'><a
name="第2_2_2b"><span lang=EN-US style='font-family:宋体;color:red'>b)</span></a><span
lang=EN-US style='font-family:宋体;color:red'> </span><span lang=ZH-CN
style='font-family:宋体;color:red'>逻辑运算符</span><span lang=EN-US style='font-family:
宋体;color:red'><o:p></o:p></span></p>

<p class=MsoNormal style='margin-bottom:6.0pt;text-indent:24.0pt;mso-char-indent-count:
2.0;line-height:17.0pt;mso-line-height-rule:exactly;tab-stops:45.8pt 91.6pt 137.4pt 183.2pt 229.0pt 274.8pt 320.6pt 366.4pt 412.2pt 458.0pt 503.8pt 549.6pt 595.4pt 641.2pt 687.0pt 732.8pt;
mso-char-indent-size:12pt'><span lang=EN-US style='font-size:12.0pt;font-family:
宋体'>Fortran</span><span lang=ZH-CN style='font-size:12.0pt;font-family:宋体'>有</span><span
lang=EN-US style='font-size:12.0pt;font-family:宋体'>5</span><span lang=ZH-CN
style='font-size:12.0pt;font-family:宋体'>个逻辑运算符，每个操作符两边都有一点，不可省略：</span><span
lang=EN-US style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>

<table class=MsoNormalTable border=1 cellspacing=0 cellpadding=0
 style='margin-left:20.9pt;border-collapse:collapse;mso-table-layout-alt:fixed;
 border:none;mso-border-alt:solid windowtext .75pt;mso-padding-alt:0cm 1.4pt 0cm 1.4pt'>
 <tr style='mso-yfti-irow:0'>
  <td width=94 valign=top style='width:70.85pt;border:solid windowtext 1.0pt;
  mso-border-alt:solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=center style='text-align:center;line-height:17.0pt;
  mso-line-height-rule:exactly'><span lang=ZH-CN style='font-size:12.0pt;
  font-family:宋体'>逻辑运算符</span><span lang=EN-US style='font-size:12.0pt;
  font-family:宋体'><o:p></o:p></span></p>
  </td>
  <td width=104 valign=top style='width:77.95pt;border:solid windowtext 1.0pt;
  border-left:none;mso-border-left-alt:solid windowtext .75pt;mso-border-alt:
  solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=center style='text-align:center;line-height:17.0pt;
  mso-line-height-rule:exactly'><span lang=ZH-CN style='font-size:12.0pt;
  font-family:宋体'>含义</span><span lang=EN-US style='font-size:12.0pt;font-family:
  宋体'><o:p></o:p></span></p>
  </td>
  <td width=104 valign=top style='width:78.0pt;border:solid windowtext 1.0pt;
  border-left:none;mso-border-left-alt:solid windowtext .75pt;mso-border-alt:
  solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=center style='text-align:center;line-height:17.0pt;
  mso-line-height-rule:exactly'><span lang=ZH-CN style='font-size:12.0pt;
  font-family:宋体'>逻辑运算例</span><span lang=EN-US style='font-size:12.0pt;
  font-family:宋体'><o:p></o:p></span></p>
  </td>
  <td width=359 valign=top style='width:269.3pt;border:solid windowtext 1.0pt;
  border-left:none;mso-border-left-alt:solid windowtext .75pt;mso-border-alt:
  solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=center style='text-align:center;line-height:17.0pt;
  mso-line-height-rule:exactly'><span lang=ZH-CN style='font-size:12.0pt;
  font-family:宋体'>例子含义</span><span lang=EN-US style='font-size:12.0pt;
  font-family:宋体'><o:p></o:p></span></p>
  </td>
 </tr>
 <tr style='mso-yfti-irow:1;mso-yfti-lastrow:yes'>
  <td width=94 valign=top style='width:70.85pt;border:solid windowtext 1.0pt;
  border-top:none;mso-border-top-alt:solid windowtext .75pt;mso-border-alt:
  solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=left style='margin-left:18.15pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>.AND.<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:18.15pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>.OR.<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:18.15pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>.NOT.<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:18.15pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>.EQV.<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:18.15pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>.NEQV.<o:p></o:p></span></p>
  </td>
  <td width=104 valign=top style='width:77.95pt;border-top:none;border-left:
  none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
  mso-border-top-alt:solid windowtext .75pt;mso-border-left-alt:solid windowtext .75pt;
  mso-border-alt:solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>逻辑与</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>逻辑或</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>逻辑非</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>逻辑等价</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>逻辑不等价</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>
  </td>
  <td width=104 valign=top style='width:78.0pt;border-top:none;border-left:
  none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
  mso-border-top-alt:solid windowtext .75pt;mso-border-left-alt:solid windowtext .75pt;
  mso-border-alt:solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>A.AND.B<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>A.OR.B<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>.NOT.A<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>A.EQV.B<o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:12.85pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>A.NEQV.B<o:p></o:p></span></p>
  </td>
  <td width=359 valign=top style='width:269.3pt;border-top:none;border-left:
  none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
  mso-border-top-alt:solid windowtext .75pt;mso-border-left-alt:solid windowtext .75pt;
  mso-border-alt:solid windowtext .75pt;padding:0cm 1.4pt 0cm 1.4pt'>
  <p class=MsoNormal align=left style='margin-left:5.65pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>A</span><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>，</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>B</span><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>为真时，则</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>A.AND.B</span><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>为真</span><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'><o:p></o:p></span></p>
  <p class=MsoNormal align=left style='margin-left:5.65pt;text-align:left;
  line-height:17.0pt;mso-line-height-rule:exactly'><span lang=EN-US
  style='font-size:12.0pt;font-family:宋体'>A</span><span lang=ZH-CN
  style='font-size:12.0pt;font-family:宋体'>，</span><span lang=EN-US