How can I display high precision number in engineering format?

I need to display my results in engineering format with large exponential values( for eg. 3.14159e-070). 'format longE' doesn't helps in this case. I used vpa function but it displays the result in expanded format (for eg. 0.000000000000000000000000000000000000000000000000000000000000000000000000003141592653589793299). How can I display my results in exponential form with high negative powers? Thanks in advance.

Answer 1

[Star Strider]

I wrote a utility function for my own use that you may find useful:

engstr = @(x) [x*10.^(-3*floor(log10(abs(x))/3))  3*floor(log10(abs(x))/3)];
Q1 = Your_Number_Here;
Result2 = sprintf('%.4fe%+04d', engstr(Q1))

The ‘engstr’ function calculates the mantissa and exponent as a (1x2) vector. The ‘Result2’ assignment demonstrates a way to print them.

[Star Strider]

Sree Ranjini’s ‘Answer’ moved here:

Thanks for your advice. When I tried to apply this code on vpa output it shows the error "Error using sprintf Function is not defined for 'sym' inputs"

[Star Strider]

My pleasure.

Use double instead of vpa, or change the ‘Result2’ assignment to:

Result2 = sprintf('%.4fe%+04d', engstr(double(Q1)))

That should work.

[Walter Roberson]

It won't display the results in high precision with accuracy. The question is about reformatting a high precision symbolic number to still have high precision but engineering format. (I think. The text and the tags are not entirely clear about it.)