Formatting of result values.

For example, x=0.0012345678.

How can I get x to be in the format 0.123457*10^(-2). There are six significant digits and if more than six decimal places, which are converted to standard format by rounding.

Thank you！

Answer 1

[Star Strider]

That is not a format MATLAB will do automatically.

I wrote a utility function for my own use for such requirements —

x=0.0012345678;
lod = 1;
rfd = @(x,lod) [x*(10.^(-fix(log10(x)-lod+1))), fix(log10(x)-lod+1)];   % Anonymous Function Creating Reformatted Number
Out = sprintf('%.6fE%+d',  rfd(x,lod))                                  % Character Vector With Formatted Output

Out = '0.123457E-2'

Experiment with it if necessary. MATLAB maintains full precision internally regardless of the way the numbers are formatted.

.

Answer 2

[John D'Errico]

You cannot write it in that form, at least not easily. Yes, you could write a formatting code. But you would need to write it, separating out the exponent, then building it as a string.

You CAN use an exponential format, like this:

format short e
x=0.0012345678

x = 
   1.2346e-03

But if you want that specific 10^-2 form, that will take more work.