how to print E formated numbers.

I have numbers such as 0.1032E-02 (say) If I read this as x = 0.1032E-02 and save it to a text file using fopen, and fprintf fid = fopen('Testing.txt','wt'); fprintf(fid, '%15.5E\n',x) it always prints x as 1.032E-03 but I would like the 0 in front just as the way I assigned the value to x. How do i do it?

[Stephen23]

@Pappu Murthy: Numeric data classes do not store any formatting, so printing a number "just as the way I assigned the value to x" is not possible in general: a value will simply be displayed according to the fprintf specification. With that in mind: if you need to convert to numeric, do you always want a leading zero in the printed output?

[Pappu Murthy]

Yes. I want the numbers printed as 0.0000E-nn format with leading zero. But fprintf does not let the leading zero.

Answer 1

[Star Strider]

Try this little utility anonymous function I wrote a while back to solve this exact problem:

a = 0.1032E-02
expstr = @(x) [x*10.^floor(-log10(abs(x)))  floor(log10(abs(x))+1)];
Result = sprintf('%.7fE%+03d', expstr(a))

Result =
    '0.1032000E-02'

[Pappu Murthy]

This seemed to have worked fine. However, I still have a problem. In order to make the question easy to understand, I over simplified it. I am actually calculating internally the numbers (not reading it like I showed here). Once calculated I need to print them to a file where I need that leading zero.. Not sure your little script can do that. Otherwise you have answered my question for sure..

[Jan]

@Pappu: It does not matter where the numbers are coming from. You can replace the sprintf by fprintf also to write the output to a file.

[Star Strider]

@Jan — Thank you!

[Pappu Murthy]

It worked like charm. I am going to use this now. Thanks for all the help.

[Star Strider]

As always, my (our) pleasure!