# work with numbers in number

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Lev Mihailov on 19 Nov 2019
Answered: Walter Roberson on 19 Nov 2019
Hello! I have the number 40.201109, I need to work with numbers 109, and then with 110 and at the end of 40. Help me how to separate them

Lev Mihailov on 19 Nov 2019
201 will not be used, but they are needed for other purposes.
40.201109 from this I should get 55.201992
Walter Roberson on 19 Nov 2019
You do not understand how you get that number.
If you have a number of the form AB.cdefgh then how should the output be formed?
Lev Mihailov on 19 Nov 2019
Here is an example of some mathematical operations that I can do with a pen, I need to automate it all
40.201109 a=40 b=110 c=109
x1=c+b*10^-5;
x2=x1+a-b;
x3=x2+c-x1^2
x4=......
x124=55.201992
there are many operations, but if I can get a, b, c, I can fully calculate everything

Walter Roberson on 19 Nov 2019
x = 40.201109;
xs = sprintf('%.6f', x);
a = str2double(xs(1:2));
b = str2double(xs(end-3:end-1));
c = str2double(xs(end-2:end));
This presumes there are exactly 6 significant decimal places. It is not generally possible to figure out how many significant decimal places a binary floating point number has -- for example 40.201109 is stored internally as 40.201109000000002424712874926626682281494140625 exactly.