Welcome to MapForums!

When you are signed in, this message, the ads in this row, and the red-underlined link ads all go away.

## MapPoint drive speed legitimacy

This is a discussion on MapPoint drive speed legitimacy within the Development forums, part of the MapPoint Desktop Discussion category; I'm automating MapPoint through Excel VBA and I've run into a peculiarity. I'm doing a route analysis and setting my ...

1. Junior Member White Belt
Join Date
Nov 2009
Posts
2

## MapPoint drive speed legitimacy

I'm automating MapPoint through Excel VBA and I've run into a peculiarity. I'm doing a route analysis and setting my driver profile speeds on all roads to 45 mph. Every route I'm analyzing has a start point and an end point with no stops in between. I'm having the program spit back both the drive time and drive distance. My segment preferences are set to 0 (fastest route). Now, for a given route, MapPoint will spit back a drive time of, say, 116 minutes and a route distance of 105.82 miles. However, 105.82 miles in 116 minutes translates to 54.7 mph. Furthermore, if I'm driving the same speed on every road, my fastest route should be the same as my shortest route and changing my segment preference option from fastest route to shortest route should have no effect on the output. It does. I know MapPoint is reading the speeds I'm entering because when I change the speed of a given road class to some outlandish number like 200 mph while holding all the other speeds constant, my drive time is drastically shortened. Does anyone have any insight into why this sort of thing should happen?

2. Junior Member Yellow Belt
Join Date
Oct 2009
Location
UK
Posts
26

## Re: MapPoint drive speed legitimacy

maybe there is a minimum speed for motorways, irrespective of the speed you enter.

look at the actual route that gets generated, see if that helps.

3. Senior Member Blue Belt
Join Date
Oct 2003
Location
London
Posts
290

## Re: MapPoint drive speed legitimacy

I work in the UK. This is a bit of conjecture but I think the reason that you get the counter-intuitive results you describe may include:

1. I don’t think the smallest roads (B roads and minor roads in the UK) have their default speed changed by objRoute.DriverProfile.Speed (). Presumably the logic being that most routing is focused on the primary road network.
2. There are time penalties for junctions, roundabouts etc that severely decrease average speeds in urban areas, which is a valid assumption although if true it would be nice to know what the penalty is.

An example of the first. If I set the 5 speed options to 45km/h and ask for the quickest route in a rural area then typically I’ll be directed along a maze of tiny roads avoiding A-roads and higher. But I get an average speed significantly over 45km/h.

An example of the second. If, with the 5 options again set to 45km/h, I plan the quickest route from Chingford in North London to Hayes in South London (believe me a very urban journey) the distance is 34.8km, time is 68mins so an average speed of around 31km/h. Setting the speeds to default results in a similar route comprising 35.6km taking 43 mins (av speed of around 50km/h which is really going it!!)

Overall I’m not that surprised you get strange results when you set the road speeds unrealistically. Wouldn't the obvious thing be to play the game and set realistic speeds and differentials between different classes of road!

Also Gemma the Husky’s hypothesis shouldn’t hold if my ideas are right – a journey along a motorway should have an average speed of almost exactly 45km/h because this class of road is definitely included in the classification and there are only 2 junctions.

Anyway these are just some observations and I hope they help. In my work I don’t particularly use MP for routing – a more usual application for me is drawing drive-time catchment areas around locations like shopping centres, airports etc. Based on experience of clients pointing out 'quirks' I now always check and manually amend catchments in light of inconsistencies!

4. ## Re: MapPoint drive speed legitimacy

Another thing to check: Some route parameters are reset when you run the Route.Clear() method. Yes it is a bit annoyong. Off the top of my head, I can't remember which are reset - but I'm pretty certain either Route Preferences or Road Speeds are (or possible both!).

Try setting all parameters after a 'Clear' and before the 'Calculate'.

Richard

5. Junior Member White Belt
Join Date
Nov 2009
Posts
2

## Re: MapPoint drive speed legitimacy

Thanks for all your suggestios, everyone. Still working to find a solution.

6. Junior Member Yellow Belt
Join Date
Oct 2009
Location
UK
Posts
26

## Re: MapPoint drive speed legitimacy

just come back on

when you calculate the route you can get timings of each checkpoin/instruction - can you not use that to see exactly what is going on?

maybe your speed values just arent "taking effect" for some reason.

do your times change, if you change the speed values?

7. Executive Assistant White Belt
Join Date
Aug 2010
Location
Richmond, VA
Posts
1

## Re: MapPoint drive speed legitimacy

Has anyone been able to actually verify the drive times in MapPoint? I've been asked to create drive times in Dallas, TX at 5:00 p.m. (which should be "rush hour") from a central location to several of our company locations. I created the same route earlier in the day and later in the eveing and no matter what time I choose, I get the same travel time which can't be correct. Any suggestions?

8. Senior Member Black Belt
Join Date
Nov 2004
Location
Belgium
Posts
2,433

## Re: MapPoint drive speed legitimacy

Hi,

Mappoint does not calculate different in rush hours. This is also normal because the traffic jam is unpredictable. Presides that it is different in each country, different during holiday periods, different if schools are closed etc..