Help with string manipulation

[jkub]

Im making a compact speedometer script for experimentational purposes. I know there are is already a selection of speedometers uploaded but I want to learn a basic one myself. I calculated the speed and other things correctly but my main problem here is that I am almost clueless when it comes to manipulating strings. I have did something quite similar to this before and now instead of a "minute.second" format im gonna need a mph format for example "248" Right now I just get "2.48"

Ive tried looking at string.sub and string.format in the lua website but I cant get much out of it. However the only thing I am or seem to be understanding is the number that I put in will change the amount of visible charecters. For example

"speedStr = string.format ( "%.2f", speedSub )" that two allows me to get somthing like this 2.48 where if I changed it to 3 I would get something like 2.485(some other number)

It says there I can use different letters and only two charecters are for strings. I have no clue what each of them does all though Ive tried all of them to see if I could get lucky... No luck

Here is some of the code

function calculateSpeedAndHealth()
local clientVeh = getPedOccupiedVehicle ( getLocalPlayer() )
local velX, velY, velZ = getElementVelocity ( clientVeh )
local realSpeed = ( velX^2 + velY^2 + velZ^2 )^( 0.5 )
--
local vehHealth = getElementHealth ( clientVeh )
--
speedSub = string.sub ( realSpeed, 1, 4 )
speedStr = string.format ( "%.2f", speedSub )
healthString = string.sub ( vehHealth, 1, 3 )
guiSetText ( speedNumber, "Mph: " ..speedStr )
if ( vehHealth >= 1000 ) then
guiSetText ( healthNumber, "Health: 1000" )
else
guiSetText ( healthNumber, "Health: " ..healthString )
end
if isPedInVehicle ( getLocalPlayer() ) then
--
else
guiSetVisible ( speedometer, false )
removeEventHandler ( "onClientRender", getRootElement(), calculateSpeedAndHealth )
end
end

You can also see I used string.sub which from what I understands does ALMOST the same thing as that number I mentioned that changed the ammount of numbers

Please help me with this

[eAi]

String formatting syntax is well documented all over the place.

http://en.wikipedia.org/wiki/Printf#pri ... aceholders would be a reasonable place to start.

%.3f means a floating point number (a number with a decimal point) with 3 numbers after the decimal point. %d would be an integer (no decimal places). So maybe you want "%d Miles Per Hour" or something?

[50p]

248
2.48

Don't you see any similarities? How about moving decimal point to the right by 2 places? Do you remember basic multiplications by 10, 100, 1000, etc.?

Look in there https://community.multitheftauto.com/index.html?p ... tails&id=5 You will find out what I did to display speed.

[jkub]

I used 50p's method of multiplying by 100 and eAi's "%d" suggestion. It worked Perfectly!

This is exactly what I was wanting I have been wondering this for so long. Ill take a look at that page and try to interpret:)

Thanks so Much Guys!