This is a graph of the equation y = cot x = 1/tan x. There are discontinuities at the points x = 0, x=-π, and x = π for which y is undefined.
+-------------------------------------------------------------------------------------------------+
|      #                                         |     #                                          | 2.5000
|      #                                         |     #                                          | 2.3333
|       #                                        |      #                                         | 2.1666
|       #                                        |      #                                         | 2.0000
|        #                                       |       #                                        | 1.8333
|        #                                       |       #                                        | 1.6666
|         #                                      |        #                                       | 1.5000
|          #                                     |         #                                      | 1.3333
|           #                                    |          #                                     | 1.1666
|            #                                   |           #                                    | 1.0000
|             ##                                 |            ##                                  | .83333
|               #                                |              #                                 | .66666
|                ##                              |               ##                               | .50000
|                  ###                           |                 ###                            | .33333
|                     ##                         |                    ##                          | .16666
|-----------------------###----------------------|----------------------###-----------------------| .00000
|                          ##                    |                         ##                     | -.1666
|                            ###                 |                           ###                  | -.3333
|                               ##               |                              ##                | -.5000
|                                 #              |                                #               | -.6666
|                                  ##            |                                 ##             | -.8333
|                                    #           |                                   #            | -1.000
|                                     #          |                                    #           | -1.166
|                                      #         |                                     #          | -1.333
|                                       #        |                                      #         | -1.500
|                                        #       |                                       #        | -1.666
|                                         #      |                                        #       | -1.833
|                                         #      |                                        #       | -2.000
|                                          #     |                                         #      | -2.166
|                                          #     |                                         #      | -2.333
|                                           #    |                                          #     | -2.500
+-------------------------------------------------------------------------------------------------+
 A                       A                       A                       A                       A
-π                     -π/2                      0                      π/2                      π