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POProblem with iostream,first write file in Binary mode then convert to and save ASCII
 

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  1. POProblem with iostream,first write file in Binary mode then convert to and save ASCII
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    <p>I am using iostream to collect data from a device.First I Write file in ASCII mode,it works well,but taking quite alot of time.Then I switsch to write in Binary mode and it is faster.</p> <pre><code>float dist[41616]; ofstream d_ofs( "numbers.dat",ios::out |ios::app|ios::binary); // this is from the device API getting distance datas res = GetDistances (hnd, dist, sizeof dist); d_ofs.write((char*)&amp;dist,sizeof dist); d_ofs.close(); </code></pre> <p>After the data collection,I have to convert the data inside "numbers.txt" to be readable by my tutor, in a txt file.I assume it is to change binary raw data to ASCII. so I read the file first and then write in ASCII format.</p> <p>I get numbers,but unfortunately they are not the right numbers.I guess there should be special format for this convert process.But so far I have not found the solution due to my poor coding knowledge.So can anyone give me a hand? Many thanks in advance.</p> <p>Here is my code:</p> <pre><code>double fnum[41616]; // here is the mistake,it should be float[] ifstream in("numbers.dat", ios::in | ios::binary); in.read((char *) &amp;fnum, sizeof fnum); MessageBox("Read File done"); ofstream fout("output.txt"); for(int k=0; k&lt;41616; k++) // show values read from file fout &lt;&lt;dec&lt;&lt;"\t" &lt;&lt; fnum[k] ; in.close(); fout.close(); </code></pre> <p>Conclude:</p> <p>The stupid mistake by me is in the data type.I wrote double[] instead of float[] in the second part.It is really embarrasing.Hopefully this post can help beginners like me.</p>
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    1. COHow are you writing those numbers to numbers.txt, exactly?
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    2. COJust edit my post and provide more information.
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