fix t0, tf variable

[ocots]

No description provided.

[ocots]

@jbcaillau Please review and merge.

[jbcaillau]

👍🏽 @ocots looks like the two points below from #15 (comment) are addressed:

• the standard behaviour is (i) to forbid (= throw an exception) passing a variable to a Fixed problem, (ii) to force passing a variable to a NonFixed = Variable problem
• two exceptions to (ii): for a dim $1$ variable equal either to t0 or tf, allow not to give t0 or tf when calling a flow

[jbcaillau]

@ocots final thoughts: do we agree that calling a flow is the only case when default arguments (here t0 and tf) may also be variable, hence creating a (functional but bizarre) duplication?

If yes, please merge 🤞🏾

[ocots]

@ocots final thoughts: do we agree that calling a flow is the only case when default arguments (here t0 and tf) may also be variable, hence creating a (functional but bizarre) duplication?

If yes, please merge 🤞🏾

I think yes. Note that when calling the flow, we could integrate until a time smaller than tf.

[jbcaillau]

@ocots final thoughts: do we agree that calling a flow is the only case when default arguments (here t0 and tf) may also be variable, hence creating a (functional but bizarre) duplication?
If yes, please merge 🤞🏾

I think yes. Note that when calling the flow, we could integrate until a time smaller than tf.

@ocots Ouh, very good point 👍🏽. Do we agree that the current behaviour is that f(t0, x0, p0, t1) with the final time being the only variable (similar case for initial time or both times variable) sets the variable to t1?

On top of that, need to document this (-> new issue).

[ocots]

@ocots final thoughts: do we agree that calling a flow is the only case when default arguments (here t0 and tf) may also be variable, hence creating a (functional but bizarre) duplication?
If yes, please merge 🤞🏾

I think yes. Note that when calling the flow, we could integrate until a time smaller than tf.

@ocots Ouh, very good point 👍🏽. Do we agree that the current behaviour is that f(t0, x0, p0, t1) with the final time being the only variable (similar case for initial time or both times variable) sets the variable to t1?

We agree. Note that if there are both variables. It is intended that the variable is in order the initial time and then the final. Not the converse.

On top of that, need to document this (-> new issue).