# Symplify symbolic expression instead of outputting very large denominator values

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monkey_matlab on 3 Jun 2017
Commented: Walter Roberson on 3 Jun 2017
Hello,
In this code:
z = 1;
Q = z^2 -1.368*z + 0.368 + 0.368*k*z + 0.264*k
I get the answer as:
Q =
(79*k)/125 - 1/9007199254740992
Is it possible to leave the final equation like this form:
Q = 0.632*k
Thanks.

Star Strider on 3 Jun 2017
Use the vpa function:
Q = vpa(Q,4)
Q =
0.632*k
##### 3 CommentsShow 1 older commentHide 1 older comment
Star Strider on 3 Jun 2017
The imaginary part is essentially 0.
The only option that works is to use the children function:
syms k
Q = (79*k)/125 - 1/9007199254740992;
Q = children(Q);
Q = vpa(Q(1),4)
Q =
0.632*k
Walter Roberson on 3 Jun 2017
That is not imaginary part, that is due to round-off and representation issues.
Take each of your numbers and wrap them with sym() with 'd' option. Like instead 0.368 code sym(0.368,'d')

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