# drafting6_alonosnat_project

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## Comments and Questions

globals [ tick-delta ;; how much we advance the tick counter this time through max-tick-delta ;; the largest tick-delta is allowed to be init-avg-speed init-avg-energy ;; initial averages avg-speed avg-energy ;; current averages fast medium slow ;; current counts percent-fast percent-medium ;; percentage of the counts percent-slow ;; percentage of the counts ] breed [riders rider] ;; breed [particles particle ] riders-own [energy speed flockmates ;; agentset of nearby turtles nearest-neighbor ;; closest one of our flockmates ] particles-own [ speed mass energy ;; particle info last-collision ] to setup ca ask patches [ setup-road ] setup-riders setup-particels ; do-plots end to setup-road ;; patch procedure ifelse ( pycor < 18) and ( pycor > -18 ) [ set pcolor red - 3 ] [set pcolor black] end to setup-riders create-riders number-cyclists [ set color yellow set size 4 ;; easier to see setxy random-xcor random-ycor ] end to setup-particels set-default-shape particles "circle" set max-tick-delta 0.1073 make-particles update-variables set init-avg-speed avg-speed set init-avg-energy avg-energy ; setup-plots ; setup-histograms ; do-plotting end ;to do-plots ; set-current-plot "cyclist-energy" ; plot count ;end to go go-riders go-particels end to go-riders ask riders [ flock ] ;; the following line is used to make the turtles ;; animate more smoothly. repeat 20 [ ask turtles [ fd 0.2 ] display ] ;; for greater efficiency, at the expense of smooth ;; animation, substitute the following line instead: ;; ask turtles [ fd 1 ] tick end to flock ;; turtle procedure find-flockmates if any? flockmates [ find-nearest-neighbor ifelse distance nearest-neighbor < minimum-separation [ separate ] [ align cohere ] ] end to find-flockmates ;; turtle procedure set flockmates other turtles in-radius vision end to find-nearest-neighbor ;; turtle procedure set nearest-neighbor min-one-of flockmates [distance myself] end ;;; SEPARATE to separate ;; turtle procedure turn-away ([heading] of nearest-neighbor) max-separate-turn end to align ;; turtle procedure turn-towards average-flockmate-heading max-align-turn set heading 90 end ;;; GOAL ;to goal ; set heading 90 ;end to-report average-flockmate-heading ;; turtle procedure ;; We can't just average the heading variables here. ;; For example, the average of 1 and 359 should be 0, ;; not 180. So we have to use trigonometry. let x-component sum [sin heading] of flockmates let y-component sum [cos heading] of flockmates ifelse x-component = 0 and y-component = 0 [ report heading ] [ report atan x-component y-component ] end ;;; COHERE to cohere ;; turtle procedure turn-towards average-heading-towards-flockmates max-cohere-turn end to-report average-heading-towards-flockmates ;; turtle procedure ;; "towards myself" gives us the heading from the other turtle ;; to me, but we want the heading from me to the other turtle, ;; so we add 180 let x-component mean [sin (towards myself + 180)] of flockmates let y-component mean [cos (towards myself + 180)] of flockmates ifelse x-component = 0 and y-component = 0 [ report heading ] [ report atan x-component y-component ] end ;;; HELPER PROCEDURES to turn-towards [new-heading max-turn] ;; turtle procedure turn-at-most (subtract-headings new-heading heading) max-turn end to turn-away [new-heading max-turn] ;; turtle procedure turn-at-most (subtract-headings heading new-heading) max-turn end ;; turn right by "turn" degrees (or left if "turn" is negative), ;; but never turn more than "max-turn" degrees to turn-at-most [turn max-turn] ;; turtle procedure ifelse abs turn > max-turn [ ifelse turn > 0 [ rt max-turn ] [ lt max-turn ] ] [ rt turn ] end to go-particels ask particles [ move-particels ] ask particles [ if collide? [check-for-collision] ] ; ifelse (trace?) ; [ ask particle 0 [ pen-down ] ] ; [ ask particle 0 [ pen-up ] ] tick-advance tick-delta if floor ticks > floor (ticks - tick-delta) [ update-variables ; do-plotting ] calculate-tick-delta display end to update-variables ; set medium count particles with [color = green] ; set slow count particles with [color = blue] ; set fast count particles with [color = red] set percent-medium (medium / count particles) * 100 set percent-slow (slow / count particles) * 100 set percent-fast (fast / count particles) * 100 set avg-speed mean [speed] of particles set avg-energy mean [energy] of particles end to calculate-tick-delta ;; tick-delta is calculated in such way that even the fastest ;; particle will jump at most 1 patch length in a tick. As ;; particles jump (speed * tick-delta) at every tick, making ;; tick length the inverse of the speed of the fastest particle ;; (1/max speed) assures that. Having each particle advance at most ;; one patch-length is necessary for them not to jump over each other ;; without colliding. ifelse any? particles with [speed > 0] [ set tick-delta min list (1 / (ceiling max [speed] of particles)) max-tick-delta ] [ set tick-delta max-tick-delta ] end to move-particels ;; particle procedure if patch-ahead (speed * tick-delta) != patch-here [ set last-collision nobody ] jump (speed * tick-delta) end to check-for-collision ;; particle procedure ;; Here we impose a rule that collisions only take place when there ;; are exactly two particles per patch. if count other particles-here = 1 [ ;; the following conditions are imposed on collision candidates: ;; 1. they must have a lower who number than my own, because collision ;; code is asymmetrical: it must always happen from the point of view ;; of just one particle. ;; 2. they must not be the same particle that we last collided with on ;; this patch, so that we have a chance to leave the patch after we've ;; collided with someone. let candidate one-of other particles-here with [who < [who] of myself and myself != last-collision] ;; we also only collide if one of us has non-zero speed. It's useless ;; (and incorrect, actually) for two particles with zero speed to collide. if (candidate != nobody) and (speed > 0 or [speed] of candidate > 0) [ collide-with candidate set last-collision candidate ask candidate [ set last-collision myself ] ] ] end to collide-with [ other-particle ] ;; particle procedure ;;; PHASE 1: initial setup ;; for convenience, grab some quantities from other-particle let mass2 [mass] of other-particle let speed2 [speed] of other-particle let heading2 [heading] of other-particle ;; since particles are modeled as zero-size points, theta isn't meaningfully ;; defined. we can assign it randomly without affecting the model's outcome. let theta (random-float 360) ;;; PHASE 2: convert velocities to theta-based vector representation ;; now convert my velocity from speed/heading representation to components ;; along theta and perpendicular to theta let v1t (speed * cos (theta - heading)) let v1l (speed * sin (theta - heading)) ;; do the same for other-particle let v2t (speed2 * cos (theta - heading2)) let v2l (speed2 * sin (theta - heading2)) ;;; PHASE 3: manipulate vectors to implement collision ;; compute the velocity of the system's center of mass along theta let vcm (((mass * v1t) + (mass2 * v2t)) / (mass + mass2) ) ;; now compute the new velocity for each particle along direction theta. ;; velocity perpendicular to theta is unaffected by a collision along theta, ;; so the next two lines actually implement the collision itself, in the ;; sense that the effects of the collision are exactly the following changes ;; in particle velocity. set v1t (2 * vcm - v1t) set v2t (2 * vcm - v2t) ;;; PHASE 4: convert back to normal speed/heading ;; now convert my velocity vector into my new speed and heading set speed sqrt ((v1t ^ 2) + (v1l ^ 2)) set energy (0.5 * mass * (speed ^ 2)) ;; if the magnitude of the velocity vector is 0, atan is undefined. but ;; speed will be 0, so heading is irrelevant anyway. therefore, in that ;; case we'll just leave it unmodified. if v1l != 0 or v1t != 0 [ set heading (theta - (atan v1l v1t)) ] ;; and do the same for other-particle ask other-particle [ set speed sqrt ((v2t ^ 2) + (v2l ^ 2)) set energy (0.5 * mass * (speed ^ 2)) if v2l != 0 or v2t != 0 [ set heading (theta - (atan v2l v2t)) ] ] ;; PHASE 5: final updates ;; now recolor, since color is based on quantities that may have changed ; recolor ; ask other-particle ; [ recolor ] end ;to recolor ;; particle procedure ; ifelse speed < (0.5 * 10) ; [ ; set color blue ; ] ; [ ; ifelse speed > (1.5 * 10) ; [ set color red ] ; [ set color green ] ; ] ;end ;;; ;;; drawing procedures ;;; ;; creates initial particles to make-particles create-particles number-of-particles [ setup-particle random-position set color 9 ask particles [ set size 0.5 ] ; recolor ] calculate-tick-delta end to setup-particle ;; particle procedure set speed init-particle-speed set mass particle-mass set energy (0.5 * mass * (speed ^ 2)) set last-collision nobody end ;; place particle at random location inside the box. to random-position ;; particle procedure setxy ((1 + min-pxcor) + random-float ((2 * max-pxcor) - 2)) ((1 + min-pycor) + random-float ((2 * max-pycor) - 2)) end to-report last-n [n the-list] ifelse n >= length the-list [ report the-list ] [ report last-n n butfirst the-list ] end

There is only one version of this model, created over 13 years ago by osnat gal.

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osnat gal

## הרוכבים עולים אחד על השני (Question)

למרות הנסיונות להגדיל את הטלאים או להקטין את הרוכבים, עדיין הרוכבים עולים אחד על השני. יש לך רעיון איך להתמודד עם זה? תודה

## Posted over 13 years ago

osnat gal

## הרוכבים עולים אחד על השני (Question)

למרות הנסיונות להגדיל את הטלאים או להקטין את הרוכבים, עדיין הרוכבים עולים אחד על השני. יש לך רעיון איך להתמודד עם זה? תודה

## Posted over 13 years ago

Sharona T Levy

## אני מקווה ששוחחנו על זה

1

## Posted over 13 years ago