def longest_ones(x):
"""
return the indicies of the longest stretch of contiguous ones in x,
assuming x is a vector of zeros and ones.
If there are two equally long stretches, pick the first
"""
x = asarray(x)
if len(x)==0: return array([])
#print 'x', x
ind = find(x==0)
if len(ind)==0: return arange(len(x))
if len(ind)==len(x): return array([])
y = zeros( (len(x)+2,), Int)
y[1:-1] = x
d = diff(y)
#print 'd', d
up = find(d == 1);
dn = find(d == -1);
#print 'dn', dn, 'up', up,
ind = find( dn-up == max(dn - up))
# pick the first
if iterable(ind): ind = ind[0]
ind = arange(up[ind], dn[ind])
return ind
def hist(y, bins=10, normed=0):
"""
Return the histogram of y with bins equally sized bins. If bins
is an array, use the bins. Return value is
(n,x) where n is the count for each bin in x
If normed is False, return the counts in the first element of the
return tuple. If normed is True, return the probability density
n/(len(y)*dbin)
If y has rank>1, it will be raveled
Credits: the Numeric 22 documentation
"""
y = asarray(y)
if len(y.shape)>1: y = ravel(y)
if not iterable(bins):
ymin, ymax = min(y), max(y)
if ymin==ymax:
ymin -= 0.5
ymax += 0.5
bins = linspace(ymin, ymax, bins)
n = searchsorted(sort(y), bins)
n = diff(concatenate([n, [len(y)]]))
if normed:
db = bins[1]-bins[0]
return 1/(len(y)*db)*n, bins
else:
return n, bins
def longest_ones(x):
"""
return the indicies of the longest stretch of contiguous ones in x,
assuming x is a vector of zeros and ones.
If there are two equally long stretches, pick the first
"""
x = asarray(x)
if len(x) == 0: return array([])
#print 'x', x
ind = find(x == 0)
if len(ind) == 0: return arange(len(x))
if len(ind) == len(x): return array([])
y = zeros((len(x) + 2, ), Int)
y[1:-1] = x
d = diff(y)
#print 'd', d
up = find(d == 1)
dn = find(d == -1)
#print 'dn', dn, 'up', up,
ind = find(dn - up == max(dn - up))
# pick the first
if iterable(ind): ind = ind[0]
ind = arange(up[ind], dn[ind])
return ind
def hist(y, bins=10, normed=0):
"""
Return the histogram of y with bins equally sized bins. If bins
is an array, use the bins. Return value is
(n,x) where n is the count for each bin in x
If normed is False, return the counts in the first element of the
return tuple. If normed is True, return the probability density
n/(len(y)*dbin)
If y has rank>1, it will be raveled
Credits: the Numeric 22 documentation
"""
y = asarray(y)
if len(y.shape) > 1: y = ravel(y)
if not iterable(bins):
ymin, ymax = min(y), max(y)
if ymin == ymax:
ymin -= 0.5
ymax += 0.5
bins = linspace(ymin, ymax, bins)
n = searchsorted(sort(y), bins)
n = diff(concatenate([n, [len(y)]]))
if normed:
db = bins[1] - bins[0]
return 1 / (len(y) * db) * n, bins
else:
return n, bins
def longest_contiguous_ones(x):
"""
return the indicies of the longest stretch of contiguous ones in x,
assuming x is a vector of zeros and ones.
"""
if len(x)==0: return array([])
ind = find(x==0)
if len(ind)==0: return arange(len(x))
if len(ind)==len(x): return array([])
y = zeros( (len(x)+2,), x.typecode())
y[1:-1] = x
dif = diff(y)
up = find(dif == 1);
dn = find(dif == -1);
ind = find( dn-up == max(dn - up))
ind = arange(take(up, ind), take(dn, ind))
return ind
def longest_contiguous_ones(x):
"""
return the indicies of the longest stretch of contiguous ones in x,
assuming x is a vector of zeros and ones.
"""
if len(x) == 0: return array([])
ind = find(x == 0)
if len(ind) == 0: return arange(len(x))
if len(ind) == len(x): return array([])
y = zeros((len(x) + 2, ), typecode(x))
y[1:-1] = x
dif = diff(y)
up = find(dif == 1)
dn = find(dif == -1)
ind = find(dn - up == max(dn - up))
ind = arange(take(up, ind), take(dn, ind))
return ind
def trapz(x, y):
if len(x)!=len(y):
raise ValueError, 'x and y must have the same length'
if len(x)<2:
raise ValueError, 'x and y must have > 1 element'
return asum(0.5*diff(x)*(y[1:]+y[:-1]))
def trapz(x, y):
if len(x) != len(y):
raise ValueError, 'x and y must have the same length'
if len(x) < 2:
raise ValueError, 'x and y must have > 1 element'
return asum(0.5 * diff(x) * (y[1:] + y[:-1]))
