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Convex polygon

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20: 424: 166:: Any two convex polygons with no points in common have a separator line. If the polygons are closed and at least one of them is compact, then there are even two parallel separator lines (with a gap between them). 476:
Every line segment between two points in the interior, or between two points on the boundary but not on the same edge, is strictly interior to the polygon (except at its endpoints if they are on the edges).
150:: For every collection of at least three convex polygons: if all intersections of all but one polygon are nonempty, then the intersection of all the polygons is nonempty. 358: 451: 219: 353: 333: 313: 289: 269: 249: 196: 160:
of its vertices. Thus it is fully defined by the set of its vertices, and one only needs the corners of the polygon to recover the entire polygon shape.
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property: Of all triangles contained in a convex polygon, there exists a triangle with a maximal area whose vertices are all polygon vertices.
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For each edge, the interior points and the boundary points not contained in the edge are on the same side of the line that the edge defines.
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between two points of the polygon is contained in the union of the interior and the boundary of the polygon. In particular, it is a
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are less than or equal to 180 degrees, while in a strictly convex polygon all interior angles are strictly less than 180 degrees.
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The angle at each vertex contains all other vertices in its interior (except the given vertex and the two adjacent vertices).
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Chandran, Sharat; Mount, David M. (1992). "A parallel algorithm for enclosed and enclosing triangles".
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Every polygon inscribed in a circle (such that all vertices of the polygon touch the circle), if not
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For each edge, the interior points are all on the same side of the line that the edge defines.
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between two points inside or on the boundary of the polygon remains inside or on the boundary.
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is a convex polygon such that no line contains two of its edges. In a convex polygon, all
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The polygon is entirely contained in a closed half-plane defined by each of its edges.
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The following properties of a simple polygon are all equivalent to strict convexity:
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The angle at each vertex contains all other vertices in its edges and interior.
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The following properties of a simple polygon are all equivalent to convexity:
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that does not contain any edge intersects the polygon in at most two points.
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Definition and properties of convex polygons with interactive animation.
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Lassak, M. (1993). "Approximation of convex bodies by rectangles".
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International Journal of Computational Geometry & Applications
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Implicit curve § Smooth approximation of convex polygons
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The intersection of two convex polygons is a convex polygon.
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of a convex polygon is equal to its perimeter divided by
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can be inscribed in a triangle of area at most equal to
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Pages displaying short descriptions of redirect targets
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Every internal angle is strictly less than 180 degrees.
439: 361: 341: 321: 301: 277: 257: 237: 204: 184: 445: 418: 355:and the positive homothety ratio is at most 2 and 347: 327: 307: 283: 263: 243: 213: 190: 125:Additional properties of convex polygons include: 1272: 653:"What's the average width of a convex polygon?" 63:). Equivalently, a polygon is convex if every 692:http://www.rustycode.com/tutorials/convex.html 744: 561: 696: 16:Polygon that is the boundary of a convex set 751: 737: 508: – Simple polygon which is not convex 251:in the plane, we can inscribe a rectangle 697:Schorn, Peter; Fisher, Frederick (1994), 178:property: every convex polygon with area 699:"I.2 Testing the convexity of a polygon" 18: 1273: 615: 732: 673: 596: 221:. Equality holds (exclusively) for a 758: 464: 13: 23:An example of a convex polygon: a 14: 1297: 666: 520: – Points on a common circle 650: 231:property: For every convex body 229:Inscribed/inscribing rectangles 701:, in Heckbert, Paul S. (ed.), 644: 609: 590: 555: 544: 413: 407: 393: 387: 376: 370: 1: 538: 164:Hyperplane separation theorem 94:is less than or equal to 180 81: 7: 711:(Academic Press), pp.  502: – Type of plane curve 493: 10: 1302: 156:: A convex polygon is the 1167: 1113: 1053: 997: 936: 927: 819: 771: 599:"Triangle Circumscribing" 576:10.1142/S0218195992000123 132:A convex polygon may be 335:is circumscribed about 72:strictly convex polygon 447: 420: 349: 329: 309: 285: 265: 245: 215: 192: 51:. This means that the 28: 486:Every non-degenerate 448: 421: 350: 330: 310: 286: 266: 246: 216: 193: 101:Every point on every 22: 984:Nonagon/Enneagon (9) 914:Tangential trapezoid 490:is strictly convex. 446:{\displaystyle \pi } 437: 359: 339: 319: 299: 275: 255: 235: 202: 182: 154:Krein–Milman theorem 1096:Megagon (1,000,000) 864:Isosceles trapezoid 657:Math Stack Exchange 618:Geometriae Dedicata 597:Weisstein, Eric W. 176:Inscribing triangle 117:The polygon is the 1066:Icositetragon (24) 675:Weisstein, Eric W. 630:10.1007/BF01263495 603:Wolfram Math World 532:Tangential polygon 443: 416: 345: 325: 305: 281: 261: 241: 214:{\displaystyle 2A} 211: 188: 170:Inscribed triangle 29: 1286:Types of polygons 1268: 1267: 1109: 1108: 1086:Myriagon (10,000) 1071:Triacontagon (30) 1035:Heptadecagon (17) 1025:Pentadecagon (15) 1020:Tetradecagon (14) 959:Quadrilateral (4) 829:Antiparallelogram 459:self-intersecting 405: 404: × Area 385: 368: 367: × Area 348:{\displaystyle C} 328:{\displaystyle r} 308:{\displaystyle R} 284:{\displaystyle C} 264:{\displaystyle r} 244:{\displaystyle C} 191:{\displaystyle A} 142:fan triangulation 61:self-intersecting 1293: 1081:Chiliagon (1000) 1061:Icositrigon (23) 1040:Octadecagon (18) 1030:Hexadecagon (16) 934: 933: 753: 746: 739: 730: 729: 725: 704:Graphics Gems IV 688: 687: 678:"Convex polygon" 661: 660: 648: 642: 641: 613: 607: 606: 594: 588: 587: 559: 553: 548: 523: 465:Strict convexity 452: 450: 449: 444: 425: 423: 422: 417: 406: 403: 386: 383: 369: 366: 354: 352: 351: 346: 334: 332: 331: 326: 314: 312: 311: 306: 290: 288: 287: 282: 270: 268: 267: 262: 250: 248: 247: 242: 220: 218: 217: 212: 197: 195: 194: 189: 1301: 1300: 1296: 1295: 1294: 1292: 1291: 1290: 1281:Convex geometry 1271: 1270: 1269: 1264: 1163: 1117: 1105: 1049: 1015:Tridecagon (13) 1005:Hendecagon (11) 993: 929: 923: 894:Right trapezoid 815: 767: 757: 723: 709:Morgan Kaufmann 669: 664: 649: 645: 614: 610: 595: 591: 560: 556: 549: 545: 541: 521: 512:Convex polytope 506:Concave polygon 496: 467: 438: 435: 434: 402: 382: 365: 360: 357: 356: 340: 337: 336: 320: 317: 316: 300: 297: 296: 276: 273: 272: 256: 253: 252: 236: 233: 232: 203: 200: 199: 183: 180: 179: 148:Helly's theorem 84: 76:interior angles 17: 12: 11: 5: 1299: 1289: 1288: 1283: 1266: 1265: 1263: 1262: 1257: 1252: 1247: 1242: 1237: 1232: 1227: 1222: 1220:Pseudotriangle 1217: 1212: 1207: 1202: 1197: 1192: 1187: 1182: 1177: 1171: 1169: 1165: 1164: 1162: 1161: 1156: 1151: 1146: 1141: 1136: 1131: 1126: 1120: 1118: 1111: 1110: 1107: 1106: 1104: 1103: 1098: 1093: 1088: 1083: 1078: 1073: 1068: 1063: 1057: 1055: 1051: 1050: 1048: 1047: 1042: 1037: 1032: 1027: 1022: 1017: 1012: 1010:Dodecagon (12) 1007: 1001: 999: 995: 994: 992: 991: 986: 981: 976: 971: 966: 961: 956: 951: 946: 940: 938: 931: 925: 924: 922: 921: 916: 911: 906: 901: 896: 891: 886: 881: 876: 871: 866: 861: 856: 851: 846: 841: 836: 831: 825: 823: 821:Quadrilaterals 817: 816: 814: 813: 808: 803: 798: 793: 788: 783: 777: 775: 769: 768: 756: 755: 748: 741: 733: 727: 726: 721: 694: 689: 668: 667:External links 665: 663: 662: 643: 608: 589: 570:(2): 191–214. 554: 542: 540: 537: 536: 535: 529: 524: 518:Cyclic polygon 515: 509: 503: 495: 492: 484: 483: 480: 477: 474: 466: 463: 455: 454: 442: 427: 415: 412: 409: 401: 398: 395: 392: 389: 381: 378: 375: 372: 364: 344: 324: 304: 280: 260: 240: 226: 210: 207: 187: 173: 167: 161: 151: 145: 130: 123: 122: 115: 112: 109: 106: 99: 92:internal angle 83: 80: 57:simple polygon 37:convex polygon 15: 9: 6: 4: 3: 2: 1298: 1287: 1284: 1282: 1279: 1278: 1276: 1261: 1260:Weakly simple 1258: 1256: 1253: 1251: 1248: 1246: 1243: 1241: 1238: 1236: 1233: 1231: 1228: 1226: 1223: 1221: 1218: 1216: 1213: 1211: 1208: 1206: 1203: 1201: 1200:Infinite skew 1198: 1196: 1193: 1191: 1188: 1186: 1183: 1181: 1178: 1176: 1173: 1172: 1170: 1166: 1160: 1157: 1155: 1152: 1150: 1147: 1145: 1142: 1140: 1137: 1135: 1132: 1130: 1127: 1125: 1122: 1121: 1119: 1116: 1115:Star polygons 1112: 1102: 1101:Apeirogon (∞) 1099: 1097: 1094: 1092: 1089: 1087: 1084: 1082: 1079: 1077: 1074: 1072: 1069: 1067: 1064: 1062: 1059: 1058: 1056: 1052: 1046: 1045:Icosagon (20) 1043: 1041: 1038: 1036: 1033: 1031: 1028: 1026: 1023: 1021: 1018: 1016: 1013: 1011: 1008: 1006: 1003: 1002: 1000: 996: 990: 987: 985: 982: 980: 977: 975: 972: 970: 967: 965: 962: 960: 957: 955: 952: 950: 947: 945: 942: 941: 939: 935: 932: 926: 920: 917: 915: 912: 910: 907: 905: 902: 900: 897: 895: 892: 890: 887: 885: 882: 880: 879:Parallelogram 877: 875: 874:Orthodiagonal 872: 870: 867: 865: 862: 860: 857: 855: 854:Ex-tangential 852: 850: 847: 845: 842: 840: 837: 835: 832: 830: 827: 826: 824: 822: 818: 812: 809: 807: 804: 802: 799: 797: 794: 792: 789: 787: 784: 782: 779: 778: 776: 774: 770: 765: 761: 754: 749: 747: 742: 740: 735: 734: 731: 724: 722:9780123361554 718: 714: 710: 706: 705: 700: 695: 693: 690: 685: 684: 679: 676: 671: 670: 658: 654: 647: 639: 635: 631: 627: 623: 619: 612: 604: 600: 593: 585: 581: 577: 573: 569: 565: 558: 552: 547: 543: 533: 530: 528: 525: 519: 516: 513: 510: 507: 504: 501: 498: 497: 491: 489: 481: 478: 475: 472: 471: 470: 462: 460: 440: 432: 428: 410: 399: 396: 390: 379: 373: 362: 342: 322: 302: 294: 278: 258: 238: 230: 227: 224: 223:parallelogram 208: 205: 185: 177: 174: 171: 168: 165: 162: 159: 155: 152: 149: 146: 143: 139: 135: 131: 128: 127: 126: 121:of its edges. 120: 116: 113: 110: 107: 104: 100: 97: 93: 89: 88: 87: 79: 77: 73: 68: 66: 62: 58: 54: 50: 46: 42: 38: 34: 26: 21: 1179: 1054:>20 sides 989:Decagon (10) 974:Heptagon (7) 964:Pentagon (5) 954:Triangle (3) 849:Equidiagonal 703: 681: 656: 646: 621: 617: 611: 602: 592: 567: 563: 557: 546: 500:Convex curve 485: 468: 456: 291:such that a 228: 175: 169: 134:triangulated 124: 103:line segment 85: 71: 69: 53:line segment 43:that is the 36: 30: 1250:Star-shaped 1225:Rectilinear 1195:Equilateral 1190:Equiangular 1154:Hendecagram 998:11–20 sides 979:Octagon (8) 969:Hexagon (6) 944:Monogon (1) 786:Equilateral 651:Belk, Jim. 624:: 111–117. 158:convex hull 138:linear time 119:convex hull 1275:Categories 1255:Tangential 1159:Dodecagram 937:1–10 sides 928:By number 909:Tangential 889:Right kite 539:References 431:mean width 293:homothetic 140:through a 82:Properties 49:convex set 1235:Reinhardt 1144:Enneagram 1134:Heptagram 1124:Pentagram 1091:65537-gon 949:Digon (2) 919:Trapezoid 884:Rectangle 834:Bicentric 796:Isosceles 773:Triangles 683:MathWorld 638:119508642 441:π 397:≤ 380:≤ 27:pentagon. 1210:Isotoxal 1205:Isogonal 1149:Decagram 1139:Octagram 1129:Hexagram 930:of sides 859:Harmonic 760:Polygons 494:See also 488:triangle 45:boundary 33:geometry 1230:Regular 1175:Concave 1168:Classes 1076:257-gon 899:Rhombus 839:Crossed 584:1168956 96:degrees 41:polygon 25:regular 1240:Simple 1185:Cyclic 1180:Convex 904:Square 844:Cyclic 806:Obtuse 801:Kepler 719:  636:  582:  90:Every 1215:Magic 811:Right 791:Ideal 781:Acute 634:S2CID 295:copy 59:(not 47:of a 39:is a 1245:Skew 869:Kite 764:List 717:ISBN 713:7–15 429:The 384:Area 65:line 35:, a 626:doi 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Index


regular
geometry
polygon
boundary
convex set
line segment
simple polygon
self-intersecting
line
interior angles
internal angle
degrees
line segment
convex hull
triangulated
linear time
fan triangulation
Helly's theorem
Krein–Milman theorem
convex hull
Hyperplane separation theorem
parallelogram
homothetic
mean width
self-intersecting
triangle
Convex curve
Concave polygon
Convex polytope

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