need helps to explain C++ codes

[rizalafande]

codes in c++

hi,
due to i have no knowledge about c++ at all, can anyone help me to translate below code into c languages?
======================

for (inter=0; inter<6; inter++) {
start = ldtogfxp ( (long double) (inter ? -(1 << (inter - 1)) : 0) );
end = ldtogfxp ( (long double) ( - (1 << inter)) ) + 1.0;
aInterval[inter].intWidth = (end - start) / LUTsize;
delta = gfxptold (aInterval[inter].intWidth);
}

=======================

attached is the header files that related with this code.

 

[GSM Man]

c++ cpdes

That's not C++ - it looks like ANSI C to me. As a C programmer what part don't you understand.

 

[rizalafande]

explain c++

actually, i would like to seek the answer for 'delta' when 'inter = 1'. as a c programmer, i know how the system computes the bitwise left shift operation ( 1 << inter ...) in 'start' and 'end' functions. the only thing that make me confuse is what is the purpose of term 'ldtogfxp' which stated in both functions. once i know how it works, then i think i should be able to understand how the delta value being computed. hope you can share with me some lights. thanks.

 

[GSM Man]

explain c++

If you look at the header file you'll see that 'ldtogfxp' is a function that converts a 'long double' to a 'gFXP' type. gFXP is typedefed as a 'long double'. So what the function is doing is converting a 'long double' to a 'long double'. Presumably 'gFXP' is encoded in some way- the header file indicates it's a 'guarded LNS'. From the name I'd guess that maybe it's a fixed point value. So you really have no way of knowing unless you have the source code to the 'ldtogfxp' function or some documentatin that explains the data types.

 

[rizalafande]

thanks. i had now got the result of 'delta'.