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copied!<p>Using C, I would do something like this (untested):</p> <pre><code>#include <stdio.h> #define MAX 128 char buf[MAX]; while (fgets(buf, sizeof buf, fp) != NULL) { double d1, d2; if (buf[0] == '\n') { /* saw blank line */ } else if (sscanf(buf, "%lf%lf", &d1, &d2) != 2) { /* buf has the next text token, including '\n' */ } else { /* use the two doubles, d1, and d2 */ } } </code></pre> <p>The check for blank line is first because it's relatively inexpensive. Depending upon your needs:</p> <ol> <li>you might need to increase/change <code>MAX</code>,</li> <li>you may need to check if <code>buf</code> ends with a newline, if it doesn't, then the line was too long (go to 1 or 3 in that case),</li> <li>you might need a function that reads full lines from a file, using <code>malloc()</code> and <code>realloc()</code> to dynamically allocate the buffer (see <a href="http://www.cpax.org.uk/prg/writings/fgetdata.php" rel="nofollow noreferrer">this</a> for more),</li> <li>you might want to take care of special cases such as a single floating-point value on a line (which I assume is not going to happen). <code>sscanf()</code> returns the number of input items successfully matched and assigned.</li> </ol> <p>I am also assuming that blank lines are really blank (just the newline character by itself). If not, you will need to skip leading white-space. <code>isspace()</code> in <code>ctype.h</code> is useful in that case.</p> <p><code>fp</code> is a valid <code>FILE *</code> object returned by <code>fopen()</code>.</p>

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