I want to plot time series with pyqtgraph, and display the date and/or time on the x axis scale, but I couldn't find how to do it.
Edit 1 :
It seems like I should subclass AxisItem and reimplement tickStrings(). I'll look into this.
Edit 2 :
Here is how I subclassed AxisItem. The documentation shows how to use the class.
from __future__ import print_function
from PySide.QtCore import *
from PySide.QtUiTools import *
from PySide.QtGui import *
import pyqtgraph as pg
import time
## Reimplements c pyqtgraph.AxisItem to display time series.
# code
# from caxistime import CAxisTime
# # class definition here...
# self.__axisTime=CAxisTime(orientation='bottom')
# self.__plot=self.__glyPlot.addPlot(axisItems={'bottom': self.__axisTime}) # __plot : PlotItem
# endcode
class CAxisTime(pg.AxisItem):
## Formats axis label to human readable time.
# @param[in] values List of c time_t.
# @param[in] scale Not used.
# @param[in] spacing Not used.
def tickStrings(self, values, scale, spacing):
strns = []
for x in values:
try:
strns.append(time.strftime("%H:%M:%S", time.gmtime(x))) # time_t --> time.struct_time
except ValueError: # Windows can't handle dates before 1970
strns.append('')
return strns
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