Pandas timeseries plot setting x-axis major and minor ticks and labels

Question

I want to be able to set the major and minor xticks and their labels for a time series graph plotted from a Pandas time series object     The Pandas 0 9  what s new  page says        you can either use to pydatetime or register a converter for the   Timestamp type    but I can t work out how to do that so that I can use the matplotlib ax xaxis set major locator and ax xaxis set major formatter  and minor  commands   If I use them without converting the pandas times  the x-axis ticks and labels end up wrong   By using the  xticks  parameter I can pass the major ticks to pandas plot  and then set the major tick labels  I can t work out how to do the minor ticks using this approach   I can set the labels on the default minor ticks set by pandas plot   Here is my test code   import pandas print  pandas   version   is    pandas   version   print  matplotlib   version   is    matplotlib   version        dStart   datetime datetime 2011 5 1    1 May dEnd   datetime datetime 2011 7 1    1 July      dateIndex   pandas date range start dStart  end dEnd  freq  D   print  1 May to 1 July 2011   dateIndex        testSeries   pandas Series data np random randn len dateIndex                               index dateIndex       ax   plt figure figsize  7 4   dpi 300  add subplot 111  testSeries plot ax ax  style  v-   label  first line          using MatPlotLib date time locators and formatters doesn t work with new   pandas datetime index ax xaxis set minor locator matplotlib dates WeekdayLocator byweekday  1                                                              interval 1   ax xaxis set minor formatter matplotlib dates DateFormatter   d n a    ax xaxis grid True  which  minor   ax xaxis grid False  which  major   ax xaxis set major formatter matplotlib dates DateFormatter   n n n b Y    plt show          set the major xticks and labels through pandas ax2   plt figure figsize  7 4   dpi 300  add subplot 111  xticks   pandas date range start dStart  end dEnd  freq  W-Tue   print  xticks     xticks testSeries plot ax ax2  style  -v   label  second line                   xticks xticks to pydatetime    ax2 set xticklabels  x strftime   a n d n h n Y   for x in xticks      set the text of the first few minor ticks created by pandas plot      ax2 set xticklabels   a   b   c   d   e    minor True    remove the minor xtick labels set by pandas plot  ax2 set xticklabels     minor True    turn the minor ticks created by pandas plot off    plt minorticks off   plt show   print testSeries  6 4 2011   6 7 2011     and its output   pandas   version   is  0 9 1 dev-3de54ae matplotlib   version   is  1 1 1 1 May to 1 July 2011  lt class  pandas tseries index DatetimeIndex  gt   2011-05-01 00 00 00       2011-07-01 00 00 00  Length  62  Freq  D  Timezone  None     xticks    lt class  pandas tseries index DatetimeIndex  gt   2011-05-03 00 00 00       2011-06-28 00 00 00  Length  9  Freq  W-TUE  Timezone  None     2011-06-04   -0 199393 2011-06-05   -0 043118 2011-06-06    0 477771 2011-06-07   -0 033207 Freq  D   Update  I ve been able to get closer to the layout I wanted by using a loop to build the major xtick labels     only show month for first label in month month   dStart month - 1 xticklabels      for x in xticks      if  month    x month           xticklabels append x strftime   d n a n h            month   x month     else          xticklabels append x strftime   d n a      However  this is a bit like doing the x-axis using ax annotate  possible but not ideal

User · Accepted Answer

Both pandas and matplotlib dates use matplotlib units for locating the ticks    But while matplotlib dates has convenient ways to set the ticks manually  pandas seems to have the focus on auto formatting so far  you can have a look at the code for date conversion and formatting in pandas    So for the moment it seems more reasonable to use matplotlib dates  as mentioned by  BrenBarn in his comment    import numpy as np import pandas as pd import matplotlib pyplot as plt  import matplotlib dates as dates  idx   pd date range  2011-05-01    2011-07-01   s   pd Series np random randn len idx    index idx   fig  ax   plt subplots   ax plot date idx to pydatetime    s   v-   ax xaxis set minor locator dates WeekdayLocator byweekday  1                                                   interval 1   ax xaxis set minor formatter dates DateFormatter   d n a    ax xaxis grid True  which  minor   ax yaxis grid   ax xaxis set major locator dates MonthLocator    ax xaxis set major formatter dates DateFormatter   n n n b n Y    plt tight layout   plt show        my locale is German  so that Tuesday  Tue  becomes Dienstag  Di

[python] Pandas timeseries plot setting x-axis major and minor ticks and labels

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