Branching about cppadcodegen HOT 6 CLOSED

take a look at things like CppAD::CondExpLt

from cppadcodegen.

I would suggest looking at
https://coin-or.github.io/CppAD/doc/condexp.htm

from cppadcodegen.

Hi,
You can write conditions which will generate if and else in the generated source code.
Since it is not possible to overload the keywords if/else, you need to write your model using special functions for this purpose.
Information about these functions is available at (as suggested by Brad):
https://coin-or.github.io/CppAD/doc/condexp.htm
You just need to use the active data type AD<CG<scalar>> (scalar can be a double for instance) and register the branches as you would normally with CppAD (using AD<scalar>).

Please also take a look at:
https://github.com/joaoleal/CppADCodeGen/blob/master/test/cppad/cg/operations/cond_exp.hpp

from cppadcodegen.

Thank you very much for your help.

I have another similar question, I did not find a way to do "if...elseif....else".
I basically need to do something similar to what this guy is doing here(beginif/BeginElseIf) with his own AD lib =>here and here.

Is there a way to do something equivalent with CppAD ?

from cppadcodegen.

It is possible to do this sort of thing by making the output of one conditional expression the input to another. For example; see
https://github.com/coin-or/CppAD/blob/master/include/cppad/core/atan2.hpp

from cppadcodegen.

CppAD(Codegen) conditional expressions (if/else) can be implemented using;:

• out = CondExpLt(a,b,c,d) --> if(a < b) {out = c} else {out = d},
• out = CondExpLe(a,b,c,d) --> if(a <= b) {out = c} else {out = d},
• out = CondExpEq(a,b,c,d) --> if(a == b) {out = c} else {out = d},
• out = CondExpGe(a,b,c,d) --> if(a >= b) {out = c} else {out = d}, and
• out = CondExpGt(a,b,c,d) --> if(a > b) {out = c} else {out = d}.

See:
https://github.com/joaoleal/CppADCodeGen/blob/6a4f6609365cb25a15e691d7357c84d293491472/include/cppad/cg/cond_exp_op.hpp

from cppadcodegen.