1. We have added a Gift Upgrades feature that allows you to gift an account upgrade to another member, just in time for the holiday season. You can see the gift option when going to the Account Upgrades screen, or on any user profile screen.
    Dismiss Notice

The Number Crunching Thread

Discussion in 'Civ5 - Strategy & Tips' started by alpaca, Oct 8, 2010.

  1. vexing

    vexing knows

    Joined:
    Dec 24, 2010
    Messages:
    2,668
    cool, nice find... finally a solid explanation of why you can go from 2 turns left to done on techs.

    this sort of makes early exploration more important, especially on higher levels where the AI is gifted some early techs
     
  2. snarzberry

    snarzberry Emperor

    Joined:
    May 28, 2010
    Messages:
    1,240
    Location:
    New Zealand
    yep, I'm glad that there is at least an explanation for it. That does my head in no end sometimes! I have this really intricate sequence of RA's signed to get me astronomy and steel after currency, chivalry and education and it's been buggered up a number of times because the UI indicates there are 2 or 3 (I've even seen 4) turns remaining to be researched on a specific tech only for it to be finished next turn. Many thanks for the reason, don't see why the discount can't be taken into account for the displayed info.
     
  3. MouseyPounds

    MouseyPounds Prince

    Joined:
    Nov 8, 2010
    Messages:
    417
    Location:
    Maryland, USA
    Now that the UI properly displays the adjusted tech cost, the research formula is easier to test. Civ5 does indeed divide by the total # of civs like DaveMcW suggested, but it also uses a 1/(1+x) relationship.

    Given the following:
    • B is the base cost of a tech; i.e. the XML cost with map size, handicap, and gamespeed modifiers already applied
    • K is the number of known, living civs who have the tech.
    • T is the total number of living civs in the game.
    • M is the TECH_COST_TOTAL_KNOWN_TEAM_MODIFIER global define (30 in unmodded game)
    The adjusted tech cost, C is:
    C = ceiling( B / ( 1 + floor( M * K / T ) / 100 ) )

    or, prettier:


    Some further examples are spoiled below.
    Spoiler :

    Prince, Huge, Standard speed game (1.3 modifier) with 12 civs.
    Researching Gunpowder (B = 840 * 1.3 = 1092)
    All civs still alive so T = 12.
    Unmodded, so M = 30.

    Here are the different costs for various numbers of known civs who have the tech:
    Code:
    K    C
    --  ----
    0   1092
    1   1071
    2   1040
    3   1021
    4    993
    5    975
    6    950
    7    934
    8    910
    9    896
    10   874
    11   860
    12   840
    
    Note that the last entry doesn't really matter since at 
    this point everyone in the game knows the tech.
    Now for a similar game but with a total of 22 civs instead of 12:
    Code:
    K    C
    --  ----
    0  1092
    1  1082
    2  1071
    3  1050
    4  1040
    5  1031
    6  1012
    7  1002
    8   993
    9   975
    10  967
    11  950
    12  942
    13  934
    14  918
    15  910
    16  903
    17  888
    18  881
    19  874
    20  860
    21  854
    22  840
    Finally, in that same 22 Civ game researching Chemistry (B = 1404)
    C is 1338 if everyone's alive and 4 known civs have it (K = 4 and T = 22)
    C drops to 1325 if 3 of the civs that don't have it are killed (K=4 and T=19)
    C increases back to 1338 if one of the civs that did have it is killed (K=3 and T=18)
     
  4. vexing

    vexing knows

    Joined:
    Dec 24, 2010
    Messages:
    2,668
    i wonder if that was intended only for teams, given that it is called team modifier.


    simplified an approximation is the tech cost multiplied by 1 / (1 + .3 * percent of known civs with tech)
    if all civs are known and have it, it costs 23% less, if half know it costs 13% less... with standard's 8 civs, if 7 know, it's about 21% less
     
  5. Bungle

    Bungle Chieftain

    Joined:
    May 14, 2011
    Messages:
    99
    Location:
    Norway
    I have something for you math buffs to look at :)

    Continued from this thread: Can anyone figure out what determines a City State's beakers per turn?
     
  6. KrikkitTwo

    KrikkitTwo Immortal

    Joined:
    Apr 3, 2004
    Messages:
    12,316
  7. DaveMcW

    DaveMcW Deity

    Joined:
    Oct 8, 2002
    Messages:
    6,489
    (x-1)^2 * 9 + 25
     
  8. vexing

    vexing knows

    Joined:
    Dec 24, 2010
    Messages:
    2,668
    it's the same as before, the multiplier changed to 3, the exponent 2.01

    floor( 25 + ( 3 * ( policy number - 1 ) ) ^ 2.01 * (1 + number of cities policy cost mod * ( number of cities - 1 ) / 100 ) * policy percent handicap modifier * game speed culture percent * (100 - cristo redentor + piety finisher reductions) / 100 / 5 ) * 5

    number of cities policy cost mod is 15 base, 10 with representation, lower with larger than standard map sizes
    policy percent handicap modifier is .5 on settler, .67 on chieftain, .85 on warlord
    game speed is .67 on quick, 2 on epic, 3 on marathon
    cristo + piety finisher are 10 each if you have them

    the floor( x / 5) * 5 is just to round down to the nearest 5
     
  9. TyfoonTurk

    TyfoonTurk Warlord

    Joined:
    Feb 7, 2011
    Messages:
    250
    So is the mulitplier 9 (DaveMcW) or 3 (vexing)?

    EDIT: Oh i see now 9=3^2
     
  10. KrikkitTwo

    KrikkitTwo Immortal

    Joined:
    Apr 3, 2004
    Messages:
    12,316
    Is that still current?
     
  11. vexing

    vexing knows

    Joined:
    Dec 24, 2010
    Messages:
    2,668
    it's based on some numbers in the defines.xml file which have changed
    the base city growth is still 15,
    city growth multiplier is 8,
    city growth exponent is 1.5
     
  12. cryptc

    cryptc Chieftain

    Joined:
    Oct 29, 2010
    Messages:
    82
  13. vexing

    vexing knows

    Joined:
    Dec 24, 2010
    Messages:
    2,668
    this isn't really appropriate for number crunching thread, and there is a post on it in bug reports. it's 2^31 / 10000 = 214748 beakers, standard integer overflow.
    if you're making a mod i'd just lower all research costs and gains considerably, since fractional parts are kept
     
  14. cryptc

    cryptc Chieftain

    Joined:
    Oct 29, 2010
    Messages:
    82
    Sorry :blush: *is such a newb on this forum*

    Thank you though :)
     
  15. ShahJahanII

    ShahJahanII Homesick Alien

    Joined:
    Jul 19, 2011
    Messages:
    1,863
    Location:
    Austin, Texas
    Here is a mathematical question.

    In real life, if you flipped a coin 5 times and the first 4 flips got you a heads what would be the chance of getting tails on the next flip?
    Commonly Accepted Answer: 1/2,50%

    But, Rene Descartes mentioned in one of his books that you are more likely to get a tails on the next flip.
    Cartesian Answer: +1/2,>50

    How does this relate to civ?

    If you get super lucky with your capital and have 4 different luxuries, are you less likely to find resources further away from your capital?
    This was mentioned in one of wainy's Bab2lon LPs.
     
  16. KrikkitTwo

    KrikkitTwo Immortal

    Joined:
    Apr 3, 2004
    Messages:
    12,316
    Well Decartes was wrong about coins... BUT he would be right about civ, because AFAIK the game doesn't treat each tile individually (like coin flips)
     
  17. KiffeLesBiffles

    KiffeLesBiffles Do you like dogs?

    Joined:
    Apr 18, 2011
    Messages:
    385
    Location:
    Paris
    When you flip coin, you suppose the indepandance of the 5th times compare to the 4 previous flip, which is correct.

    With Civ, I bet "Find resources further away from your capital" is not independant from "have 4 different luxuries in your cap". I don't know how they distribute lux in space, but it cant be totaly random.

    BTW, i never had 4 lux in my cap in random map.
     
  18. MadDjinn

    MadDjinn Deity

    Joined:
    Jan 28, 2011
    Messages:
    4,554
    it depends on your inference point.

    If you're saying that you'd flip a coin 5 times and get heads the first four times, THEN flip the coin and get tails - of course it's less than 50%. H*H*H*H*T

    If however, you took it at the point of "What will the next flip give?" there's only 2 answers, and every flip before it didn't count, so it's 50%.

    As per the actual question:

    Yes it's more like to see 'more of the same' lux's, if you had a 4 unique lux start, than many new ones. Especially if they were calendar or trapping resources, which tend to come in clusters spread over a wide area.

    You can find more 'unique' luxs, but they'd be few and far between. (the game seems to 'spray' an area with a lux type)
     
  19. KrikkitTwo

    KrikkitTwo Immortal

    Joined:
    Apr 3, 2004
    Messages:
    12,316
    Well chance of H*H*H*H*T is Exactly equal to the chance of H*H*H*H*H

    but Both of those are less than 50% [/tangent]
     
  20. robal1991

    robal1991 Chieftain

    Joined:
    May 2, 2011
    Messages:
    74
    Location:
    Poland
    Do you know the formula for the city strenght?
    Or at least what and in what way affects the city strenght?
    I've read in manual that
    Do you know how exactly the location affects the value of city's strenght?

    Thx :)
     

Share This Page