Why is some integer in denominator kept in bracket?

[zhaoli-IHEP]

In some cases two integer denominators are not combined, so the result rational number looks strange. For example

symbol x;
Local expression = 22400/27/(2 + x)/(4 + x);
.sort
Local expr = expression*replace_(x,134);
.sort
print;
.end

This gives expr = 2800/459/(138);

[jodavies]

This is because they are still inside the internal denominator function. If you rename this, as in

CFunction den;
Denominators den;

You can see what is happening.

You can then use something like

Identify den(x?number_) = 1/x;

to get rid of them.

[tueda]

Indeed, to me, this seems to be a "normalization" bug related to the denom_ function. (Note that 22400/27/(2 + x)/(4 + x) is internally 22400/27*denom_(2 + x)*denom_(4 + x), as Josh mentioned.)

As a workaround, you can insert

argument;
endargument;

after the replacement, which should turn remaining denom_(integer) to be 1/integer.

[zhaoli-IHEP]

Thank you so much!