def uncompress_if_required(fhand):
'It returns a uncompressed handle if required'
magic = peek_chunk_from_file(fhand, 2)
if magic == '\037\213':
fhand = GzipFile(fileobj=fhand)
elif magic == 'BZ':
try:
fhand = BZ2File(fhand)
except NameError:
raise OptionalRequirementError(BZIP_ERROR)
return fhand
def get_fig_and_canvas(num_rows=1, num_cols=1, figsize=None):
if figsize is None:
height = 5.0 * num_rows
width = 7.5 * num_cols
if height > 320.0:
height = 320.0
figsize = (width, height)
try:
fig = Figure(figsize=figsize)
canvas = FigureCanvas(fig)
except NameError:
msg = 'Matplotlib module is required to draw graphical histograms'
raise OptionalRequirementError(msg)
return fig, canvas
def compress_fhand(fhand, compression_kind=None):
'Compresses the file if required'
if compression_kind == BGZF:
if fhand_is_seekable(fhand):
fhand = BgzfWriter(fileobj=fhand)
else:
raise RuntimeError('bgzf is only available for seekable files')
elif compression_kind == GZIP:
fhand = GzipFile(fileobj=fhand)
elif compression_kind == BZIP2:
mode = 'w' if 'w' in fhand.mode else 'r'
try:
fhand = BZ2File(fhand, mode=mode)
except NameError:
raise OptionalRequirementError(BZIP_ERROR)
return fhand
def get_canvas_and_axes(figure_size=FIGURE_SIZE,
left=0.1,
right=0.9,
top=0.9,
bottom=0.1,
plot_type=111):
'It returns a matplotlib canvas and axes instance'
try:
fig = Figure(figsize=FIGURE_SIZE)
canvas = FigureCanvas(fig)
except NameError:
msg = 'Matplotlib module is required to draw graphical histograms'
raise OptionalRequirementError(msg)
axes = fig.add_subplot(plot_type)
fig.subplots_adjust(left=left, right=right, top=top, bottom=bottom)
return canvas, axes
def FakeRequiredfunct(*args, **kwargs):
raise OptionalRequirementError(msg)
def __init__(self, *args, **kwargs):
raise OptionalRequirementError(msg)
