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Added dialog to hdf5 example prompting user to generate sample data

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This commit is contained in:
Luke Campagnola 2014-05-22 01:51:17 -04:00
parent 6e9d5c3cfb
commit 374b5a33ed
1 changed files with 33 additions and 16 deletions
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49
examples/hdf5.py
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@ -18,14 +18,10 @@ import pyqtgraph as pg
from pyqtgraph.Qt import QtCore, QtGui
import numpy as np
import h5py
import sys, os
if len(sys.argv) > 1:
fileName = sys.argv[1]
else:
fileName = 'test.hdf5'
if not os.path.isfile(fileName):
raise Exception("No suitable HDF5 file found. Use createFile() to generate an example file.")
pg.mkQApp()
plt = pg.plot()
plt.setWindowTitle('pyqtgraph example: HDF5 big data')
@ -101,10 +97,6 @@ class HDF5Plot(pg.PlotCurveItem):
self.scale(scale, 1) # scale to match downsampling
f = h5py.File(fileName, 'r')
curve = HDF5Plot()
curve.setHDF5(f['data'])
plt.addItem(curve)
def createFile(finalSize=2000000000):
@ -118,17 +110,42 @@ def createFile(finalSize=2000000000):
f.create_dataset('data', data=chunk, chunks=True, maxshape=(None,))
data = f['data']
for i in range(finalSize // (chunk.size * chunk.itemsize)):
newshape = [data.shape[0] + chunk.shape[0]]
data.resize(newshape)
data[-chunk.shape[0]:] = chunk
nChunks = finalSize // (chunk.size * chunk.itemsize)
with pg.ProgressDialog("Generating test.hdf5...", 0, nChunks) as dlg:
for i in range(nChunks):
newshape = [data.shape[0] + chunk.shape[0]]
data.resize(newshape)
data[-chunk.shape[0]:] = chunk
dlg += 1
if dlg.wasCanceled():
f.close()
os.remove('test.hdf5')
sys.exit()
dlg += 1
f.close()
if len(sys.argv) > 1:
fileName = sys.argv[1]
else:
fileName = 'test.hdf5'
if not os.path.isfile(fileName):
size, ok = QtGui.QInputDialog.getDouble(None, "Create HDF5 Dataset?", "This demo requires a large HDF5 array. To generate a file, enter the array size (in GB) and press OK.", 2.0)
if not ok:
sys.exit(0)
else:
createFile(int(size*1e9))
#raise Exception("No suitable HDF5 file found. Use createFile() to generate an example file.")
f = h5py.File(fileName, 'r')
curve = HDF5Plot()
curve.setHDF5(f['data'])
plt.addItem(curve)
## Start Qt event loop unless running in interactive mode or using pyside.
if __name__ == '__main__':
import sys
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtGui.QApplication.instance().exec_()