def substringView(self, i, j):
"""substringView returns modified view of the input array which
represents only the [i:j] substring of each array element.
>>> c = fromlist([["this","that"],["another", "one"]])
>>> d = c.substringView(1, 2); d
CharArray([['h', 'h'],
['n', 'n']])
>>> d[:] = [["1","2"],["3","4"]]; d
CharArray([['1', '2'],
['3', '4']])
>>> c
CharArray([['t1is', 't2at'],
['a3other', 'o4e']])
"""
n = _na.arange(self._itemsize)[i:j]
if len(n) != 0:
i = n[0]
j = n[-1] + 1
else:
i = j = 0
r = self.view()
substr_size = j - i
if substr_size < 0:
substr_size = 0
r._itemsize = substr_size
r._byteoffset += i
return r
def substringView(self, i, j):
"""substringView returns modified view of the input array which
represents only the [i:j] substring of each array element.
>>> c = fromlist([["this","that"],["another", "one"]])
>>> d = c.substringView(1, 2); d
CharArray([['h', 'h'],
['n', 'n']])
>>> d[:] = [["1","2"],["3","4"]]; d
CharArray([['1', '2'],
['3', '4']])
>>> c
CharArray([['t1is', 't2at'],
['a3other', 'o4e']])
"""
n = _na.arange(self._itemsize)[i:j]
if len(n) != 0:
i = n[0]
j = n[-1] + 1
else:
i = j = 0
r = self.view()
substr_size = j - i
if substr_size < 0:
substr_size = 0
r._itemsize = substr_size
r._byteoffset += i
return r
def proveit(N, filename="memmap.dat", pagesize=1024, mode="r"):
"""proveit is a diagnostic function which creates a file of size 'N',
memory maps it, and then reads one byte at 'pagesize' intervals."""
import numarrayall as num
import os
f = _open(filename, "w+")
f.seek(N - 1)
f.write("\0")
f.close()
m = Memmap(filename, mode=mode)
n = m[:]
a = num.NumArray(buffer=n, shape=(len(n), ), type='Int8')
a._map = m
hits = num.arange(N // pagesize) * pagesize
fetch = a[hits] # force every page into RAM
return a
def proveit(N, filename="memmap.dat", pagesize=1024, mode="r"):
"""proveit is a diagnostic function which creates a file of size 'N',
memory maps it, and then reads one byte at 'pagesize' intervals."""
import numarrayall as num
import os
f = _open(filename, "w+")
f.seek(N-1)
f.write("\0")
f.close()
m = Memmap(filename, mode=mode)
n = m[:]
a = num.NumArray(buffer=n, shape=(len(n),), type='Int8')
a._map = m
hits = num.arange(N//pagesize)*pagesize
fetch = a[ hits ] # force every page into RAM
return a
