If we want to implement stored procedure to any database, it is necessary to type below command.
createlang -d dbname plpgsql
2011/08/21
postgres tips: enable plpgsql for implementing stored procedure
This entry is just a memo for me 8^)
If we want to implement stored procedure to any database, it is necessary to type below command.
If we want to implement stored procedure to any database, it is necessary to type below command.
2011/08/16
python tips: draw beta distribution with matplotlib
ラベル:
machine learning,
python
import numpy as np
import numpy as np
import pylab as pl
import scipy.special as ss
def beta(a, b, mew):
e1 = ss.gamma(a + b)
e2 = ss.gamma(a)
e3 = ss.gamma(b)
e4 = mew ** (a - 1)
e5 = (1 - mew) ** (b - 1)
return (e1/(e2*e3)) * e4 * e5
def plot_beta(a, b):
Ly = []
Lx = []
mews = np.mgrid[0:1:100j]
for mew in mews:
Lx.append(mew)
Ly.append(beta(a, b, mew))
pl.plot(Lx, Ly, label="a=%f, b=%f" %(a,b))
def main():
plot_beta(0.1, 0.1)
plot_beta(1, 1)
plot_beta(2, 3)
plot_beta(8, 4)
pl.xlim(0.0, 1.0)
pl.ylim(0.0, 3.0)
pl.legend()
pl.show()
if __name__ == "__main__":
main()
2011/08/13
postgres tips: calculate degree with stored procedure
-- User-Defined-Function for calculate degree
-- ------------------------------------------
-- This function calculates cos from vector(0,1)
-- .. code-block:: sql
-- :linenos:
CREATE OR REPLACE FUNCTION GET_COS
(v2_x FLOAT, v2_y FLOAT)
RETURNS FLOAT AS
$$
DECLARE
v1_x FLOAT;
v1_y FLOAT;
v1_v2 FLOAT;
length_v1 FLOAT;
length_v2 FLOAT;
cos FLOAT;
BEGIN
v1_x := 0.;
v1_y := 1.;
v1_v2 := (v1_x * v2_x) + (v1_y * v2_y);
length_v1 := sqrt(power(v1_x,2) + power(v1_y,2));
length_v2 := sqrt(power(v2_x,2) + power(v2_y,2));
cos := v1_v2 / (length_v1 * length_v2);
RETURN cos;
END;
$$ language plpgsql;
-- This function calculates sin from vector(0,1)
-- .. code-block:: sql
-- :linenos:
CREATE OR REPLACE FUNCTION GET_SIN
(v2_x FLOAT, v2_y FLOAT)
RETURNS FLOAT AS
$$
DECLARE
v1_x FLOAT;
v1_y FLOAT;
det FLOAT;
length_v1 FLOAT;
length_v2 FLOAT;
sin FLOAT;
BEGIN
v1_x := 0.;
v1_y := 1.;
det := (v1_x * v2_y) - (v1_y * v2_x);
length_v1 := sqrt(power(v1_x,2) + power(v1_y,2));
length_v2 := sqrt(power(v2_x,2) + power(v2_y,2));
sin := det / (length_v1 * length_v2);
RETURN sin;
END;
$$ language plpgsql;
-- This function calculates degree from vector(0,1)
-- .. code-block:: sql
-- :linenos:
CREATE OR REPLACE FUNCTION GET_DEGREE
(x FLOAT, y FLOAT)
RETURNS FLOAT AS
$$
DECLARE
sin FLOAT;
cos FLOAT;
degree FLOAT;
BEGIN
sin := GET_SIN(x, y);
cos := GET_COS(x, y);
IF sin >= 0 AND cos >= 0 THEN
degree := degrees(acos(cos));
ELSEIF sin >= 0 AND cos < 0 THEN
degree := degrees(acos(cos));
ELSEIF sin < 0 AND cos < 0 THEN
degree := 180. - degrees(asin(sin));
ELSEIF sin < 0 AND cos >= 0 THEN
degree := 360. + degrees(asin(sin));
END IF;
RETURN degree;
END;
$$ language plpgsql;
memo for my low-memory brain: calculate intersection from two lines in 2-D.
ラベル:
math
This is my memo for basic geometry-formula.
Now, I want to calculate intersection of two lines(Line1 and Line2).
Line1: passes point (x1=0, y1=9) and (x2=2, y2=5).
Line2: passes point (x3=1, y3=1) and (x4=3, y4=0).
Firstly, we can express these lines as following:
Line1:
Line2:
Secondly, we can get intersection (x,y) by solving below linear algebra:
Finally, using inverse matrix, we can easily calculate intersection:
Now, I want to calculate intersection of two lines(Line1 and Line2).
Line1: passes point (x1=0, y1=9) and (x2=2, y2=5).
Line2: passes point (x3=1, y3=1) and (x4=3, y4=0).
Firstly, we can express these lines as following:
Line1:
Line2:
Secondly, we can get intersection (x,y) by solving below linear algebra:
Finally, using inverse matrix, we can easily calculate intersection:
sphinx tips: how to easily write a document for several scripts?
Today, I explain how to write a sphinx document for several scripts in an easy way. Assume that you are now writing postgres scripts and need to write document for them. Now, you have two postgres scripts named sample{1,2}.sql and these scripts are written like below.
As you can see above, there are rst formatted comments in sql scripts. If you write this kind of comments in sql scripts, you can easily convert them to html/latex-styled pdf! Below shell scripts can convert above sql scripts into one rst document.
Now, put all of above scripts into same sphinx-root directory and edit your index.rst for including ${output_rst}. Next, do this:
Finally, you can get document like this.
-- Sample1.sql
-- -----------
-- This SQL does something!!
-- A definition of sample_table shown below.
-- =============== =========== ============
-- Column Name Type Description
-- =============== =========== ============
-- foo TEXT foo?
-- bar TEXT bar?
-- baz FLOAT baz?
-- =============== =========== ============
-- :NOTE: just return 10 records
-- :TODO: just return 11 records
-- .. code-block:: sql
-- :linenos:
SELECT
*
FROM
sample_table
LIMIT 10;
-- Sample2.sql
-- -----------
-- This SQL extract data from columns named foo, bar...
-- :NOTE: just return 10 records
-- :TODO: just return 11 records
-- .. code-block:: sql
-- :linenos:
SELECT
foo,
bar
FROM
sample_table
LIMIT 11;
As you can see above, there are rst formatted comments in sql scripts. If you write this kind of comments in sql scripts, you can easily convert them to html/latex-styled pdf! Below shell scripts can convert above sql scripts into one rst document.
#!/bin/sh
# convert_sql2rst.sh
output_rst="sample.rst"
if [ -e ${output_rst} ]; then
rm ${output_rst}
fi
echo "=======================" >> ${output_rst}
echo "This is sample chapter!" >> ${output_rst}
echo "=======================" >> ${output_rst}
echo "" >> ${output_rst}
for sql_file in `ls *.sql`
do
echo "converting ${sql_file} to rst-formatted document..."
sed ${sql_file} -e 's/^/ /g' | \
sed -e 's/^ -- //g' >> ${output_rst}
echo "" >> ${output_rst}
echo "" >> ${output_rst}
done
Now, put all of above scripts into same sphinx-root directory and edit your index.rst for including ${output_rst}. Next, do this:
yaboo@maniac:~/Projects/SqlProject$ sh convert_sql2rst.sh converting sample.sql to rst-formatted document... converting sample2.sql to rst-formatted document... yaboo@maniac:~/Projects/SqlProject$ make html sphinx-build -b html -d _build/doctrees . _build/html Making output directory... Running Sphinx v1.0.7 loading pickled environment... not yet created building [html]: targets for 2 source files that are out of date updating environment: 2 added, 0 changed, 0 removed reading sources... [100%] sample looking for now-outdated files... none found pickling environment... done checking consistency... done preparing documents... done writing output... [100%] sample writing additional files... genindex search copying static files... done dumping search index... done dumping object inventory... done build succeeded. Build finished. The HTML pages are in _build/html.
Finally, you can get document like this.
2011/08/11
python tips: draw poisson pdf graph with matplotlib
ラベル:
machine learning,
python
this is a code for drawing a graph of poisson pdf with matplotlib.
#!/usr/bin/env python
#coding: utf-8
import pylab as pl
import numpy as np
def get_factorial(n):
if n == 0:
return 1
else:
return n * get_factorial(n-1)
def get_probability(p, n, r):
mew = float(n) * p
denom = (mew ** r) * np.exp(-1 * mew)
molec = get_factorial(r)
return denom/float(molec)
def plot_poisson_distrib(p, n, lt, lab):
xl = [nr for nr in range(0, 20, 1)]
yl = [get_probability(p, n, nr) for nr in range(0, 20, 1)]
pl.plot(xl, yl, lt, label=lab)
def main():
p = 0.02
mew = 1.0
plot_poisson_distrib(p, (mew / p), 'b-', 'P(%f,%f)' %(mew,p))
mew = 2.5
plot_poisson_distrib(p, (mew / p), 'r-', 'P(%f,%f)' %(mew,p))
mew = 5.0
plot_poisson_distrib(p, (mew / p), 'g-', 'P(%f,%f)' %(mew,p))
pl.ylabel('p(x)')
pl.xlabel('x')
pl.legend()
pl.show()
if __name__ == "__main__":
main()
and output of above code is:
python tips: draw binary pdf graph with matplotlib
ラベル:
machine learning,
python
this is a code for drawing a graph of binary probability distribution with matplotlib.
#!/usr/bin/env python
#coding: utf-8
import pylab as pl
def combination(n, r):
if (r == 0) or (n == r):
return 1.0
denom = reduce(lambda x, y: x*y, [i for i in range(1, n+1)])
mol_l = reduce(lambda x, y: x*y, [i for i in range(1, n-r+1)])
mol_r = reduce(lambda x, y: x*y, [i for i in range(1, r+1)])
return float(denom / (mol_l * mol_r))
def get_probability(p, n, r):
q = 1 - p
return combination(n, r) * (p ** r) * (q ** (n-r))
def plot_bin_distrib(p, n, lt, lab):
xl = [nr for nr in range(0, n+1, 1)]
yl = [get_probability(p, n, nr) for nr in range(0, n+1, 1)]
pl.plot(xl, yl, lt, label=lab)
def main():
p = 1.0/3.0
n = 10
plot_bin_distrib(p, n, 'b-', 'Bin(%s,%f)' %(n,p))
n = 20
plot_bin_distrib(p, n, 'r-', 'Bin(%s,%f)' %(n,p))
n = 30
plot_bin_distrib(p, n, 'g-', 'Bin(%s,%f)' %(n,p))
n = 40
plot_bin_distrib(p, n, 'y-', 'Bin(%s,%f)' %(n,p))
pl.ylabel('p(x)')
pl.xlabel('x')
pl.legend()
pl.show()
if __name__ == "__main__":
main()
and here is output from above code.
2011/08/10
python tips: use of chain generator
The book titled "Expert Python Programming" introduces pipeline of generators.
This concept is very useful for dividing loop codes to small parts.
Below is my example code that prints digit pyramid.
Result of above code is ...
This concept is very useful for dividing loop codes to small parts.
Below is my example code that prints digit pyramid.
def change_value():
for step in range(1, 10):
yield step
def create_box(steps):
for step in steps:
yield (' ').join( str(step) for i in range(2 * step - 1) )
def create_pyramid(height):
boxes = create_box(change_value())
for step, box in enumerate(boxes):
if step == height:
break
else:
print ('').join(' ' for i in range((height - step)*2)) + box
Result of above code is ...
>>> create_pyramid(9)
1
2 2 2
3 3 3 3 3
4 4 4 4 4 4 4
5 5 5 5 5 5 5 5 5
6 6 6 6 6 6 6 6 6 6 6
7 7 7 7 7 7 7 7 7 7 7 7 7
8 8 8 8 8 8 8 8 8 8 8 8 8 8 8
9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9
2011/08/07
postgres tips: stored procedure for calculating distance on the earth
CREATE FUNCTION GET_DISTANCE
(alat FLOAT, alon FLOAT, lat FLOAT, lon FLOAT)
RETURNS FLOAT AS
$$
DECLARE
radius_earth FLOAT;
radian_lat FLOAT;
radian_lon FLOAT;
distance_v FLOAT;
distance_h FLOAT;
distance FLOAT;
BEGIN
-- Insert earth radius
SELECT INTO radius_earth 6378.137;
-- Calculate difference between lat and alat
SELECT INTO radian_lat radians(lat - alat);
-- Calculate difference between lon and alon
SELECT INTO radian_lon radians(lon - alon);
-- Calculate vertical distance
SELECT INTO distance_v (radius_earth * radian_lat);
-- Calculate horizontal distance
SELECT INTO distance_h (cos(radians(alat)) * radius_earth * radian_lon);
-- Calculate distance(km) and convert it to distance(meter)
SELECT INTO distance sqrt(pow(distance_h,2) + pow(distance_v,2)) * 1000;
-- Returns distance
RETURN DISTANCE;
END;
$$ language plpgsql;
> createlang plpgsql mytestdb > psql -d mytestdb mytestdb=# CREATE FUNCTION GET_DISTANCE mytestdb-# (alat FLOAT, alon FLOAT, lat FLOAT, lon FLOAT) mytestdb-# RETURNS FLOAT AS mytestdb-# $$ mytestdb$# DECLARE mytestdb$# radius_earth FLOAT; mytestdb$# radian_lat FLOAT; mytestdb$# radian_lon FLOAT; mytestdb$# distance_v FLOAT; mytestdb$# distance_h FLOAT; mytestdb$# distance FLOAT; mytestdb$# BEGIN mytestdb$# -- Insert earth radius mytestdb$# SELECT INTO radius_earth 6378.137; mytestdb$# mytestdb$# -- Calculate difference between lat and alat mytestdb$# SELECT INTO radian_lat radians(lat - alat); mytestdb$# mytestdb$# -- Calculate difference between lon and alon mytestdb$# SELECT INTO radian_lon radians(lon - alon); mytestdb$# mytestdb$# -- Calculate vertical distance mytestdb$# SELECT INTO distance_v (radius_earth * radian_lat); mytestdb$# mytestdb$# -- Calculate horizontal distance mytestdb$# SELECT INTO distance_h (cos(radians(alat)) * radius_earth * radian_lon); mytestdb$# mytestdb$# -- Calculate distance(km) and convert it to distance(meter) mytestdb$# SELECT INTO distance sqrt(pow(distance_h,2) + pow(distance_v,2)) * 1000; mytestdb$# mytestdb$# -- Returns distance mytestdb$# RETURN DISTANCE; mytestdb$# END; mytestdb$# $$ language plpgsql; CREATE FUNCTION mytestdb=# select GET_DISTANCE(34.701909, 135.4949770, 35.681382, 139.766084); get_distance ------------------ 405807.810663345 (1 行)
latex tips: how to set up UTF-8 latex environment in Ubuntu 10.04LTS/amd64
I show you utf-8 latex installation steps for utf-8 encodings in Ubuntu-10.04 LTS (amd64) 2011/08/07. I am not sure this is the most effective way, but this can work very well on Ubuntu-10.04 LTS ;-) If you through below steps, you can compile utf-8 encoded tex files and also compile sphinx document!! (And..., if you want to convert sphinx document to pdf format and get ExtBabel error when uses "make all-pdf-ja" command, you should also check here)
Step1. install dvipsk-ja (default package is broken at 2011.06.11 JST)
Step2. install packages
Step3. update latex environment
Step4. get iso image of texlive2010 (this includes platex for utf8)
Step5. mount iso image of texlive2010
Step6. install texlive2010
Step7. check platex can corporate with utf-8 encoded text (see -kanji=STRING option)
Step1. install dvipsk-ja (default package is broken at 2011.06.11 JST)
> sudo add-apt-repository ppa:cosmos-door/dvipsk-ja > sudo aptitude update > sudo aptitude upgrade > sudo aptitude install dvipsk-ja
Step2. install packages
> sudo aptitude install texlive texlive-math-extra texlive-latex-extra texlive-latex-extra-doc texlive-fonts-extra texlive-fonts-extra-doc texlive-fonts-recommended texlive-fonts-recommended-doc texlive-formats-extra texlive-latex-recommended texlive-latex-recommended texlive-extra-utils texlive-font-utils texlive-doc-ja ptex-bin jbibtex-bin mendexk okumura-clsfiles latex-cjk-japanese cmap-adobe-japan1 cmap-adobe-japan2 cmap-adobe-cns1 cmap-adobe-gb1 gs-cjk-resource ghostscript xdvik-ja dvi2ps dvi2ps-fontdesc-morisawa5 jmpost latexmk latex-mk pybliographer yatex
Step3. update latex environment
> updmap > sudo mktexlsr > sudo updmap-sys > sudo dpkg-reconfigure ptex-jisfonts > sudo jisftconfig add
Step4. get iso image of texlive2010 (this includes platex for utf8)
Step5. mount iso image of texlive2010
sudo mount -o loop texlive2010-20100826.iso /mnt3
Step6. install texlive2010
> sudo ./install-tl ... Enter command: O [options] Enter command: L [create symlinks in standard directories] New value for binary directory [/usr/local/bin]: Enter New value for man directory [/usr/local/man]: Enter New value for info directory [/usr/local/info]: Enter Enter command: R Enter command: I Installing to: /usr/local/texlive/2010 Installing [0001/2133, time/total: ??:??/??:??]: 12many [376k] Installing [0002/2133, time/total: 00:00/00:00]: 2up [66k] Installing [0003/2133, time/total: 00:00/00:00]: ANUfinalexam [3k] Installing [0004/2133, time/total: 00:00/00:00]: AkkTeX [16k] Installing [0005/2133, time/total: 00:00/00:00]: Asana-Math [433k] Installing [0006/2133, time/total: 00:00/00:00]: ESIEEcv [137k] Installing [0007/2133, time/total: 00:01/18:36]: FAQ-en [4943k] Installing [0008/2133, time/total: 00:01/03:12]: HA-prosper [266k] Installing [0009/2133, time/total: 00:01/03:03]: IEEEconf [188k] Installing [0010/2133, time/total: 00:01/02:58]: IEEEtran [1325k] Installing [0011/2133, time/total: 00:01/02:28]: MemoirChapStyles [669k] Installing [0012/2133, time/total: 00:02/04:32]: SIstyle [338k] Installing [0013/2133, time/total: 00:02/04:22]: SIunits [284k] .... Installing [2129/2133, time/total: 03:33/03:33]: zhmetrics [66k] Installing [2130/2133, time/total: 03:33/03:33]: zhspacing [165k] Installing [2131/2133, time/total: 03:33/03:33]: ziffer [3k] Installing [2132/2133, time/total: 03:33/03:33]: zwgetfdate [242k] Installing [2133/2133, time/total: 03:33/03:33]: zwpagelayout [520k] Time used for installing the packages: 03:33 running mktexlsr /usr/local/texlive/2010/texmf-dist /usr/local/texlive/2010/texmf mktexlsr: Updating /usr/local/texlive/2010/texmf-dist/ls-R... mktexlsr: Updating /usr/local/texlive/2010/texmf/ls-R... mktexlsr: Done. writing fmtutil.cnf data to /usr/local/texlive/2010/texmf-var/web2c/fmtutil.cnf writing updmap.cfg to /usr/local/texlive/2010/texmf-config/web2c/updmap.cfg writing language.dat data to /usr/local/texlive/2010/texmf-var/tex/generic/config/language.dat writing language.def data to /usr/local/texlive/2010/texmf-var/tex/generic/config/language.def writing language.dat.lua data to /usr/local/texlive/2010/texmf-var/tex/generic/config/language.dat.lua running mktexlsr /usr/local/texlive/2010/texmf-var mktexlsr: Updating /usr/local/texlive/2010/texmf-var/ls-R... mktexlsr: Done. running updmap-sys...done re-running mktexlsr /usr/local/texlive/2010/texmf-var mktexlsr: Updating /usr/local/texlive/2010/texmf-var/ls-R... mktexlsr: Done. pre-generating all format files (fmtutil-sys --all), be patient...done running path adjustment actions finished with path adjustment actions running package specific postactions finished with package specific postactions See /usr/local/texlive/2010/index.html for links to documentation. The TeX Live web site (http://tug.org/texlive/) contains updates and corrections. TeX Live is a joint project of the TeX user groups around the world; please consider supporting it by joining the group best for you. The list of groups is available on the web at http://tug.org/usergroups.html. Add /usr/local/texlive/2010/texmf/doc/man to MANPATH, if not dynamically determined. Add /usr/local/texlive/2010/texmf/doc/info to INFOPATH. Most importantly, add /usr/local/texlive/2010/bin/x86_64-linux to your PATH for current and future sessions. Welcome to TeX Live! Logfile: /usr/local/texlive/2010/install-tl.log
Step7. check platex can corporate with utf-8 encoded text (see -kanji=STRING option)
> platex --help
Usage: ptex [option] texfile
: ptex [option] &format texfile
-fmt=NAME use NAME instead of program name or %&format.
-halt-on-error stop processing at the first error
[-no]-file-line-error disable/enable file:line:error style messages
-ini be iniptex.
-interaction=STRING set interaction mode (STRING=batchmode|nonstopmode|
scrollmode|errorstopmode)
-ipc send DVI output to a socket as well as the usual
output file
-ipc-start as -ipc, and also start the server at the other end
-jobname=STRING set the job name to STRING
-kanji=STRING set Japanese encoding (STRING=euc|jis|sjis|utf8)
-kpathsea-debug=NUMBER set path searching debugging flags according to
the bits of NUMBER
[-no]-mktex=FMT disable/enable mktexFMT generation (FMT=tex/tfm)
-mltex enable MLTeX extensions such as \charsubdef
-output-comment=STRING use STRING for DVI file comment instead of date
-output-directory=DIR use DIR as the directory to write files to
[-no]-parse-first-line disable/enable parsing of the first line of the
input file
-progname=STRING set program (and fmt) name to STRING
-recorder enable filename recorder
[-no]-shell-escape disable/enable \write18{SHELL COMMAND}
-src-specials insert source specials into the DVI file
-src-specials=WHERE insert source specials in certain places of
the DVI file. WHERE is a comma-separated value
list: cr display hbox math par parend vbox
-translate-file=TCXNAME use the TCX file TCXNAME
-help print this message and exit.
-version print version information and exit.
Email bug reports to ptex-staff@ml.asciimw.jp.
2011/08/04
hive tips: convert default separator
hive's default separator is like '^A'.
to convert '^A' to ',', use below sed script.
to convert '^A' to ',', use below sed script.
/opt/hadoop/bin/hadoop dfs -cat /user/test/* | sed 's/[Ctrl-V][Ctrl-A]/,/g' > ${outputfile}
2011/08/03
machine learning: curve-fitting
ラベル:
machine learning,
python
#coding: utf-8
import numpy as np
from pylab import *
import sys
M = 9
def y(x, wlist):
ret = wlist[0]
for i in range(1, M+1):
ret += wlist[i] * (x ** i)
return ret
def estimate(xlist, tlist, lam):
A = []
for i in range(M+1):
for j in range(M+1):
temp = (xlist**(i+j)).sum()
if i == j:
temp += lam
A.append(temp)
A = array(A).reshape(M+1, M+1)
T = []
for i in range(M+1):
T.append(((xlist**i) * tlist).sum())
T = array(T)
wlist = np.linalg.solve(A, T)
return wlist
def rms(xlist, tlist, wlist):
E_w = 0
N = len(xlist)
for n in range(0, N):
sum = 0
for j in range(0, M+1):
sum += wlist[j] * (xlist[n] ** j)
E_w += ((sum - tlist[n]) ** 2)/2
return str(np.sqrt(2 * E_w / N))
def example1():
# number of training data
N = 10
# generate training data
xlist = np.linspace(0, 1, N) # extract N-points
tlist = np.sin(2 * np.pi * xlist) + np.random.normal(0, 0.2, xlist.size)
# estimate parametaer w
wlist = estimate(xlist, tlist, np.exp(-18.0))
#print wlist
print "E_RMS for training data: %s" % rms(xlist, tlist, wlist)
N = 100
xlist2 = np.linspace(0, 1, N) # extract N-points
tlist2 = np.sin(2 * np.pi * xlist2) + np.random.normal(0, 0.2, xlist2.size)
print "E_RMS for test data: %s" % rms(xlist2, tlist2, wlist)
# generate original data
xs = np.linspace(0, 1, 1000)
# ideal and model
ideal = np.sin(2 * np.pi * xs)
model = [y(x, wlist) for x in xs]
# plot training data and original data
plot(xlist, tlist, 'bo')
plot(xlist2, tlist2, 'rd')
plot(xs, ideal, 'g-')
plot(xs, model, 'r-')
xlim(0.0, 1.0)
ylim(-1.5, 1.5)
show()
if __name__ == "__main__":
example1()
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