# How to delete/cancel trailing zeros in complex and imaginary numbers?

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Joshua Ford on 17 May 2021
Commented: Rik on 17 May 2021
Whenever I use or create imaginary and complex numbers, they are always saved with trailing zeros, for example 1.22000000 + 2.150000000i . I want to mimic the behaviour and structure of fixed-point while still being in floating-point. I want 1.22 + 2.15i. How do I delete or cancel the trailing zeros? I have tried different ways and as soon as the imaginary unit is present, the zeros come back.
Stephen on 17 May 2021
"I want 1.22 + 2.15i."
Why?
What specific operations are you performing that cannot be achieved using normal binary floating point numbers?

Rik on 17 May 2021
The way data is stored and the way it is displayed is not necessarilly connected. You can influence the way data is presented with the format function. If you want more control, you need the fprintf or sprintf functions.
format shortG
1.22 + 2.15i
ans =
1.22 + 2.15i
Rik on 17 May 2021
You already have the values very close to that. You can round to a specific number of decimals, but due to what James wrote you can't get close than this:
round(1.223 + 2.148i,2)
ans = 1.2200 + 2.1500i

Paul Hoffrichter on 17 May 2021
Edited: Paul Hoffrichter on 17 May 2021
a = 1.22000000 + 2.150000000i
a = 1.2200 + 2.1500i
fprintf("%g + %gi\n", real(a), imag(a));
1.22 + 2.15i
fprintf("%.2f + %.2fi\n", real(a), imag(a));
1.22 + 2.15i
Paul Hoffrichter on 17 May 2021
>> Does this store the numbers like this or does it only display the numbers as shown?
The storage has not changed with the choice of display.
Below shows two different variables set to a value with and without trailing zeros. But the two number numbers are represented internally exactly the same way.
a = 1.22 + 2.15i;
b = 1.22000000 + 2.150000000i;
a == b
ans = logical
1