title: Expanding a matrix according to elements in lists
body: <p>I have currently created a function which takes in two arguments.</p>
  <pre><code>function p = matr(x, phi)
       x_dir = linspace(0, x, 1);
       r = linspace(0, phi, 1);
       p = zeros(800, 2);
       p(1:400, 1) = p(1:400, 1) + x_dir.';
       p(401:800, 2) = p(401:800, 2) + r.';
  end
  </code></pre>
  <p>Which returns this matrix for the given input:</p>
  <pre><code>path = trajectory(10, pi/2)
  
  
  path =
  
       0         0
  0.0251         0
  0.0501         0
  0.0752         0
  0.1003         0
  0.1253         0
  0.1504         0
  0.1754         0
  0.2005         0
  0.2256         0
  0.2506         0
  0.2757         0
  0.3008         0
  0.3258         0
  0.3509         0
  0.3759         0
  0.4010         0
  0.4261         0
  0.4511         0
  0.4762         0
  0.5013         0
  0.5263         0
  0.5514         0
  0.5764         0
  0.6015         0
  0.6266         0
  0.6516         0
  0.6767         0
  0.7018         0
  0.7268         0
  0.7519         0
  0.7769         0
  0.8020         0
  0.8271         0
  0.8521         0
  0.8772         0
  0.9023         0
  0.9273         0
  0.9524         0
  0.9774         0
  1.0025         0
  1.0276         0
  1.0526         0
  1.0777         0
  1.1028         0
  1.1278         0
  1.1529         0
  1.1779         0
  1.2030         0
  1.2281         0
  1.2531         0
  1.2782         0
  1.3033         0
  1.3283         0
  1.3534         0
  1.3784         0
  1.4035         0
  1.4286         0
  1.4536         0
  1.4787         0
  1.5038         0
  1.5288         0
  1.5539         0
  1.5789         0
  1.6040         0
  1.6291         0
  1.6541         0
  1.6792         0
  1.7043         0
  1.7293         0
  1.7544         0
  1.7794         0
  1.8045         0
  1.8296         0
  1.8546         0
  1.8797         0
  1.9048         0
  1.9298         0
  1.9549         0
  1.9799         0
  2.0050         0
  2.0301         0
  2.0551         0
  2.0802         0
  2.1053         0
  2.1303         0
  2.1554         0
  2.1805         0
  2.2055         0
  2.2306         0
  2.2556         0
  2.2807         0
  2.3058         0
  2.3308         0
  2.3559         0
  2.3810         0
  2.4060         0
  2.4311         0
  2.4561         0
  2.4812         0
  2.5063         0
  2.5313         0
  2.5564         0
  2.5815         0
  2.6065         0
  2.6316         0
  2.6566         0
  2.6817         0
  2.7068         0
  2.7318         0
  2.7569         0
  2.7820         0
  2.8070         0
  2.8321         0
  2.8571         0
  2.8822         0
  2.9073         0
  2.9323         0
  2.9574         0
  2.9825         0
  3.0075         0
  3.0326         0
  3.0576         0
  3.0827         0
  3.1078         0
  3.1328         0
  3.1579         0
  3.1830         0
  3.2080         0
  3.2331         0
  3.2581         0
  3.2832         0
  3.3083         0
  3.3333         0
  3.3584         0
  3.3835         0
  3.4085         0
  3.4336         0
  3.4586         0
  3.4837         0
  3.5088         0
  3.5338         0
  3.5589         0
  3.5840         0
  3.6090         0
  3.6341         0
  3.6591         0
  3.6842         0
  3.7093         0
  3.7343         0
  3.7594         0
  3.7845         0
  3.8095         0
  3.8346         0
  3.8596         0
  3.8847         0
  3.9098         0
  3.9348         0
  3.9599         0
  3.9850         0
  4.0100         0
  4.0351         0
  4.0602         0
  4.0852         0
  4.1103         0
  4.1353         0
  4.1604         0
  4.1855         0
  4.2105         0
  4.2356         0
  4.2607         0
  4.2857         0
  4.3108         0
  4.3358         0
  4.3609         0
  4.3860         0
  4.4110         0
  4.4361         0
  4.4612         0
  4.4862         0
  4.5113         0
  4.5363         0
  4.5614         0
  4.5865         0
  4.6115         0
  4.6366         0
  4.6617         0
  4.6867         0
  4.7118         0
  4.7368         0
  4.7619         0
  4.7870         0
  4.8120         0
  4.8371         0
  4.8622         0
  4.8872         0
  4.9123         0
  4.9373         0
  4.9624         0
  4.9875         0
  5.0125         0
  5.0376         0
  5.0627         0
  5.0877         0
  5.1128         0
  5.1378         0
  5.1629         0
  5.1880         0
  5.2130         0
  5.2381         0
  5.2632         0
  5.2882         0
  5.3133         0
  5.3383         0
  5.3634         0
  5.3885         0
  5.4135         0
  5.4386         0
  5.4637         0
  5.4887         0
  5.5138         0
  5.5388         0
  5.5639         0
  5.5890         0
  5.6140         0
  5.6391         0
  5.6642         0
  5.6892         0
  5.7143         0
  5.7393         0
  5.7644         0
  5.7895         0
  5.8145         0
  5.8396         0
  5.8647         0
  5.8897         0
  5.9148         0
  5.9398         0
  5.9649         0
  5.9900         0
  6.0150         0
  6.0401         0
  6.0652         0
  6.0902         0
  6.1153         0
  6.1404         0
  6.1654         0
  6.1905         0
  6.2155         0
  6.2406         0
  6.2657         0
  6.2907         0
  6.3158         0
  6.3409         0
  6.3659         0
  6.3910         0
  6.4160         0
  6.4411         0
  6.4662         0
  6.4912         0
  6.5163         0
  6.5414         0
  6.5664         0
  6.5915         0
  6.6165         0
  6.6416         0
  6.6667         0
  6.6917         0
  6.7168         0
  6.7419         0
  6.7669         0
  6.7920         0
  6.8170         0
  6.8421         0
  6.8672         0
  6.8922         0
  6.9173         0
  6.9424         0
  6.9674         0
  6.9925         0
  7.0175         0
  7.0426         0
  7.0677         0
  7.0927         0
  7.1178         0
  7.1429         0
  7.1679         0
  7.1930         0
  7.2180         0
  7.2431         0
  7.2682         0
  7.2932         0
  7.3183         0
  7.3434         0
  7.3684         0
  7.3935         0
  7.4185         0
  7.4436         0
  7.4687         0
  7.4937         0
  7.5188         0
  7.5439         0
  7.5689         0
  7.5940         0
  7.6190         0
  7.6441         0
  7.6692         0
  7.6942         0
  7.7193         0
  7.7444         0
  7.7694         0
  7.7945         0
  7.8195         0
  7.8446         0
  7.8697         0
  7.8947         0
  7.9198         0
  7.9449         0
  7.9699         0
  7.9950         0
  8.0201         0
  8.0451         0
  8.0702         0
  8.0952         0
  8.1203         0
  8.1454         0
  8.1704         0
  8.1955         0
  8.2206         0
  8.2456         0
  8.2707         0
  8.2957         0
  8.3208         0
  8.3459         0
  8.3709         0
  8.3960         0
  8.4211         0
  8.4461         0
  8.4712         0
  8.4962         0
  8.5213         0
  8.5464         0
  8.5714         0
  8.5965         0
  8.6216         0
  8.6466         0
  8.6717         0
  8.6967         0
  8.7218         0
  8.7469         0
  8.7719         0
  8.7970         0
  8.8221         0
  8.8471         0
  8.8722         0
  8.8972         0
  8.9223         0
  8.9474         0
  8.9724         0
  8.9975         0
  9.0226         0
  9.0476         0
  9.0727         0
  9.0977         0
  9.1228         0
  9.1479         0
  9.1729         0
  9.1980         0
  9.2231         0
  9.2481         0
  9.2732         0
  9.2982         0
  9.3233         0
  9.3484         0
  9.3734         0
  9.3985         0
  9.4236         0
  9.4486         0
  9.4737         0
  9.4987         0
  9.5238         0
  9.5489         0
  9.5739         0
  9.5990         0
  9.6241         0
  9.6491         0
  9.6742         0
  9.6992         0
  9.7243         0
  9.7494         0
  9.7744         0
  9.7995         0
  9.8246         0
  9.8496         0
  9.8747         0
  9.8997         0
  9.9248         0
  9.9499         0
  9.9749         0
  10.000         0
       0         0
       0    0.0039
       0    0.0079
       0    0.0118
       0    0.0157
       0    0.0197
       0    0.0236
       0    0.0276
       0    0.0315
       0    0.0354
       0    0.0394
       0    0.0433
       0    0.0472
       0    0.0512
       0    0.0551
       0    0.0591
       0    0.0630
       0    0.0669
       0    0.0709
       0    0.0748
       0    0.0787
       0    0.0827
       0    0.0866
       0    0.0905
       0    0.0945
       0    0.0984
       0    0.1024
       0    0.1063
       0    0.1102
       0    0.1142
       0    0.1181
       0    0.1220
       0    0.1260
       0    0.1299
       0    0.1339
       0    0.1378
       0    0.1417
       0    0.1457
       0    0.1496
       0    0.1535
       0    0.1575
       0    0.1614
       0    0.1653
       0    0.1693
       0    0.1732
       0    0.1772
       0    0.1811
       0    0.1850
       0    0.1890
       0    0.1929
       0    0.1968
       0    0.2008
       0    0.2047
       0    0.2087
       0    0.2126
       0    0.2165
       0    0.2205
       0    0.2244
       0    0.2283
       0    0.2323
       0    0.2362
       0    0.2401
       0    0.2441
       0    0.2480
       0    0.2520
       0    0.2559
       0    0.2598
       0    0.2638
       0    0.2677
       0    0.2716
       0    0.2756
       0    0.2795
       0    0.2835
       0    0.2874
       0    0.2913
       0    0.2953
       0    0.2992
       0    0.3031
       0    0.3071
       0    0.3110
       0    0.3149
       0    0.3189
       0    0.3228
       0    0.3268
       0    0.3307
       0    0.3346
       0    0.3386
       0    0.3425
       0    0.3464
       0    0.3504
       0    0.3543
       0    0.3583
       0    0.3622
       0    0.3661
       0    0.3701
       0    0.3740
       0    0.3779
       0    0.3819
       0    0.3858
       0    0.3897
       0    0.3937
       0    0.3976
       0    0.4016
       0    0.4055
       0    0.4094
       0    0.4134
       0    0.4173
       0    0.4212
       0    0.4252
       0    0.4291
       0    0.4331
       0    0.4370
       0    0.4409
       0    0.4449
       0    0.4488
       0    0.4527
       0    0.4567
       0    0.4606
       0    0.4645
       0    0.4685
       0    0.4724
       0    0.4764
       0    0.4803
       0    0.4842
       0    0.4882
       0    0.4921
       0    0.4960
       0    0.5000
       0    0.5039
       0    0.5079
       0    0.5118
       0    0.5157
       0    0.5197
       0    0.5236
       0    0.5275
       0    0.5315
       0    0.5354
       0    0.5393
       0    0.5433
       0    0.5472
       0    0.5512
       0    0.5551
       0    0.5590
       0    0.5630
       0    0.5669
       0    0.5708
       0    0.5748
       0    0.5787
       0    0.5827
       0    0.5866
       0    0.5905
       0    0.5945
       0    0.5984
       0    0.6023
       0    0.6063
       0    0.6102
       0    0.6141
       0    0.6181
       0    0.6220
       0    0.6260
       0    0.6299
       0    0.6338
       0    0.6378
       0    0.6417
       0    0.6456
       0    0.6496
       0    0.6535
       0    0.6575
       0    0.6614
       0    0.6653
       0    0.6693
       0    0.6732
       0    0.6771
       0    0.6811
       0    0.6850
       0    0.6889
       0    0.6929
       0    0.6968
       0    0.7008
       0    0.7047
       0    0.7086
       0    0.7126
       0    0.7165
       0    0.7204
       0    0.7244
       0    0.7283
       0    0.7323
       0    0.7362
       0    0.7401
       0    0.7441
       0    0.7480
       0    0.7519
       0    0.7559
       0    0.7598
       0    0.7637
       0    0.7677
       0    0.7716
       0    0.7756
       0    0.7795
       0    0.7834
       0    0.7874
       0    0.7913
       0    0.7952
       0    0.7992
       0    0.8031
       0    0.8071
       0    0.8110
       0    0.8149
       0    0.8189
       0    0.8228
       0    0.8267
       0    0.8307
       0    0.8346
       0    0.8385
       0    0.8425
       0    0.8464
       0    0.8504
       0    0.8543
       0    0.8582
       0    0.8622
       0    0.8661
       0    0.8700
       0    0.8740
       0    0.8779
       0    0.8819
       0    0.8858
       0    0.8897
       0    0.8937
       0    0.8976
       0    0.9015
       0    0.9055
       0    0.9094
       0    0.9133
       0    0.9173
       0    0.9212
       0    0.9252
       0    0.9291
       0    0.9330
       0    0.9370
       0    0.9409
       0    0.9448
       0    0.9488
       0    0.9527
       0    0.9567
       0    0.9606
       0    0.9645
       0    0.9685
       0    0.9724
       0    0.9763
       0    0.9803
       0    0.9842
       0    0.9881
       0    0.9921
       0    0.9960
       0    1.0000
       0    1.0039
       0    1.0078
       0    1.0118
       0    1.0157
       0    1.0196
       0    1.0236
       0    1.0275
       0    1.0315
       0    1.0354
       0    1.0393
       0    1.0433
       0    1.0472
       0    1.0511
       0    1.0551
       0    1.0590
       0    1.0629
       0    1.0669
       0    1.0708
       0    1.0748
       0    1.0787
       0    1.0826
       0    1.0866
       0    1.0905
       0    1.0944
       0    1.0984
       0    1.1023
       0    1.1063
       0    1.1102
       0    1.1141
       0    1.1181
       0    1.1220
       0    1.1259
       0    1.1299
       0    1.1338
       0    1.1377
       0    1.1417
       0    1.1456
       0    1.1496
       0    1.1535
       0    1.1574
       0    1.1614
       0    1.1653
       0    1.1692
       0    1.1732
       0    1.1771
       0    1.1810
       0    1.1850
       0    1.1889
       0    1.1929
       0    1.1968
       0    1.2007
       0    1.2047
       0    1.2086
       0    1.2125
       0    1.2165
       0    1.2204
       0    1.2244
       0    1.2283
       0    1.2322
       0    1.2362
       0    1.2401
       0    1.2440
       0    1.2480
       0    1.2519
       0    1.2558
       0    1.2598
       0    1.2637
       0    1.2677
       0    1.2716
       0    1.2755
       0    1.2795
       0    1.2834
       0    1.2873
       0    1.2913
       0    1.2952
       0    1.2992
       0    1.3031
       0    1.3070
       0    1.3110
       0    1.3149
       0    1.3188
       0    1.3228
       0    1.3267
       0    1.3306
       0    1.3346
       0    1.3385
       0    1.3425
       0    1.3464
       0    1.3503
       0    1.3543
       0    1.3582
       0    1.3621
       0    1.3661
       0    1.3700
       0    1.3740
       0    1.3779
       0    1.3818
       0    1.3858
       0    1.3897
       0    1.3936
       0    1.3976
       0    1.4015
       0    1.4054
       0    1.4094
       0    1.4133
       0    1.4173
       0    1.4212
       0    1.4251
       0    1.4291
       0    1.4330
       0    1.4369
       0    1.4409
       0    1.4448
       0    1.4488
       0    1.4527
       0    1.4566
       0    1.4606
       0    1.4645
       0    1.4684
       0    1.4724
       0    1.4763
       0    1.4802
       0    1.4842
       0    1.4881
       0    1.4921
       0    1.4960
       0    1.4999
       0    1.5039
       0    1.5078
       0    1.5117
       0    1.5157
       0    1.5196
       0    1.5236
       0    1.5275
       0    1.5314
       0    1.5354
       0    1.5393
       0    1.5432
       0    1.5472
       0    1.5511
       0    1.5550
       0    1.5590
       0    1.5629
       0    1.5669
       0    1.5708
  </code></pre>
  <p>But i want to modify this function so that it can two lists like:</p>
  <pre><code>trajectory([x1, x2, x3, ... xn], [phi1, phi2, phi3, ..., phin])
  </code></pre>
  <p>and create a matrix like this:</p>
  <pre><code>trajectory =
     x1   0
     x1+k 0
     .    0
     .    0
     x1_n 0
     0    phi1
     0    phi1+k
     0    .
     0    .
     0    phi1_n
     x2   0
     x2+k 0
     .    0
     .    0
     x2_n 0
     0    phi2
     0    phi2+k
     0    .
     0    .
     0    phi2_n
     
  </code></pre>
  <p>and so on. So I was wandering if there was a more automatic way expanding the matrix, so that two lists can be provided as an input argument and the matrix expanding according to the elements of the list.</p>