Timetable Writing - 'Validate' reorders location list

All I know it the locations that get shifted aren't 'way-points' / are intermediate stops & aren't mandatory for routing trains

So, I'm working on a timetable for Oxted & when I click on the validate button, the location list gets reordered, meaning that trains don't stop where they're meant to, unless I notice and order them back again.
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All I know it the locations that get shifted aren't 'way-points' / are intermediate stops & aren't mandatory for routing trains

Put times in for ALL locations if you leave any as --/-- it confuses the sim

I have never found it to fix an error I've made, but multiple times I've had to completely re-order a train's timetable because I made a single typo, and Simsig decided that randomly reordering would help.

Somewhat apart from the issue of bad timetable data, is there any real advantage to keeping the reordering function? I have never found it to fix an error I've made, but multiple times I've had to completely re-order a train's timetable because I made a single typo, and Simsig decided that randomly reordering would help.

I think any case where the timetable is reordered brings up an error anyway - usually that the passing time at X is earlier than the passing time at Y.

The validation involves looking at just the key locations (usually major stations and junctions) and verifying that it's valid to get from A to B with the specified platform/line/path codes, if appropriate. Once that's done, the non-key locations get re-inserted. This is where the problem occurs: you have a set of locations in one order, and a set of times in a different order. So how do you re-insert when the two contradict each other?

GeoffM in post 105046 said:

The validation involves looking at just the key locations (usually major stations and junctions) and verifying that it's valid to get from A to B with the specified platform/line/path codes, if appropriate. Once that's done, the non-key locations get re-inserted. This is where the problem occurs: you have a set of locations in one order, and a set of times in a different order. So how do you re-insert when the two contradict each other?

Is the simplest answer not just to leave the timetable order and timings as-is, and to warn the user that validation has failed, asking them to go and fix the issue? That's what occurs for just about every other validation issue (e.g. trying to depart before you arrive), with invalid platform/line/path codes being the only exception I can think of currently - and even that often prompts the user if it has an issue, asking them to select a valid option.

Somewhat apart from the issue of bad timetable data, is there any real advantage to keeping the reordering function?

GeoffM in post 105046 said:

The validation involves looking at just the key locations (usually major stations and junctions) and verifying that it's valid to get from A to B with the specified platform/line/path codes, if appropriate. Once that's done, the non-key locations get re-inserted. This is where the problem occurs: you have a set of locations in one order, and a set of times in a different order. So how do you re-insert when the two contradict each other?

Is the simplest answer not just to leave the timetable order and timings as-is, and to warn the user that validation has failed, asking them to go and fix the issue?

Danny252 in post 105053 said:

GeoffM in post 105046 said:

The validation involves looking at just the key locations (usually major stations and junctions) and verifying that it's valid to get from A to B with the specified platform/line/path codes, if appropriate. Once that's done, the non-key locations get re-inserted. This is where the problem occurs: you have a set of locations in one order, and a set of times in a different order. So how do you re-insert when the two contradict each other?

Is the simplest answer not just to leave the timetable order and timings as-is, and to warn the user that validation has failed, asking them to go and fix the issue?

I'm afraid Geoff has slightly misled us in his description. It's not just timetable validation; the difficult situation is when a key location is auto-inserted. The code has to split the non-key locations either side of the insertion and that's the code that has the "interesting" behaviour. This logic gets called as part of validation and, because you don't know ahead of time whether an auto-insert will happen, it gets called for all validation.

I was wrong to refer to the sequence information in the sim data; that doesn't seem to be used. Rather, it tries to maintain time order or, if non-key locations don't have a departure or pass time, tries to maintain the original order. However, I can see that could go wrong in some cases.