Python Tips : Regular Expression usage to exclude something

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Let’s say we want to match every single rain variation ..

“Isolated rain over coastal area” is rain.
“Scattered rain over inland area” is rain.
“Rain” is rain
However..
but not “No rain” .. is Fair weather ..

#!/usr/bin/python
import re
z = 1
y = 2
x = 3
 
if (z == 1) & (x == 3) & (y == 2):
 print "match"
else:
 print "not match"
 
norain = 'No rain'
rain = 'Rain'
rainfall = 'isolated rain interne'
 
zrain  =re.compile ('(?<!No\s)[Rr]ain')
m_rain = zrain.search (rainfall)
m2_rain = zrain.search (rain)
m1_rain = zrain.search (norain)
if m_rain :
  print "got rainfall"
if m2_rain :
  print "got me : Rain"
if m1_rain:
  print "no rain also defined as rain"
else :
        print "No rain is :not raining OK!"

result would be something like follows :

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2 Responses

  1. namran says:

    the above function can be simplified a but further with the following :

    #!/usr/bin/python
 
def getBM (eng): 
    if eng == 'No rain':
        return "Tiada Hujan"
    if eng == 'Rain':
        return "Hujan"
    if eng == 'fair':
        return "Cerah" 
    if eng == 'Weather Fair':
        return "Cuaca Baik"
    if eng == 'Clear':
        return "Cerah"
    if eng == 'Hazy':
        return "Berjerebu"
    if eng == 'Windy':
        return "Berangin"
    if eng == 'No rain':
        return "Tiada Hujan"
    if eng == 'Cloudy':
        return "Mendung"
    if eng == 'Cloudy over coastal areas':
        return "Mendung di kawasan pantai"
    if eng == 'Cloudy over inland areas':
        return "Mendung di kawasan pedalaman"
    if eng == 'Rain':
        return "Hujan"
    if eng == 'Intermittent rain occasionally moderate':
        return "Hujan sekejap-sekejap kadangkala sederhana"
    if eng == 'Intermittent rain occasionally heavy':
        return "Hujan sekejap-sekejap kadangkala lebat"
    if eng == 'Windspread intermittent rain':
        return "Hujan sekejap-sekejap yang menyeluruh"
    if eng == 'Isolated rain':
        return "Hujan di satu dua tempat"
    if eng == 'Isolated rain over coastal areas':
        return "Hujan di beberapa tempat di kawasan pantai"
    if eng == 'Isolated rain over inland areas':
        return "Hujan di beberapa tempat di kawasan pedalaman"
    if eng == 'Scattered rain':
        return "Hujan curah/sementara di satu dua tempat"
    if eng == 'Scattered rain over coastal areas':
        return "Hujan curah/sementara di kawasan pantai"
    if eng == 'Scattered rain over inland areas':
        return "Hujan curah/sementara di kawasan pedalaman"
    if eng == 'Showers':
        return "Hujan curah"
    if eng == 'Isolated showers':
        return "Hujan curah di satu dua tempat"
    if eng == 'Isolated showers over coastal areas':
        return "Hujan curah di kawasan pantai"
    if eng == 'Isolated showers over inland areas':
        return "Hujan curah di kawasan pedalaman"
    if eng == 'Thunderstorms':
        return "Ribut petir"
    if eng == 'Isolated thunderstorms':
        return "Ribut petir di satu dua tempat"
    if eng == 'Scattered thunderstorms':
        return "Ribut petir di beberapa tempat"
    if eng == 'Widespread thunderstorms':
        return "Ribut petir di kebanyakan tempat"
    else:
        return eng
 
# example usage : 
print "translating 'No rain' = " + getBM("No rain")
print "translating 'No rain' = " + getBM("Scattered thunderstorms")
print "translating 'No rain' = " + getBM("Scattered rain over inland areas")

    hmm. if putting into a file and read from there would be much more better.

    Reply ↓
  2. namran says:

    yeah..

    to make it read from a text file and behave exactly as above.

    #!/usr/bin/python
 
import csv
# to read from a file with list of weather.
reader = csv.reader(open("weather_list.txt", "rb"), delimiter=':', quoting=csv.QUOTE_NONE)
# build up a reference list
kamus = {}
for row in reader:
 english_w=row[0].lstrip(' ').strip(' ')
 bm_w=row[1].lstrip(' ').strip(' ')
 kamus[english_w] = bm_w
 
# a function to return exactly the same
def getBM (eng) :
 return kamus[eng]
# example usage : 
print getBM ("Isolated showers");
print getBM ("Rain");

    then create text file with the following content.

    [namran@nb-namran Desktop]$ cat weather_list.txt 
Weather Fair:Tiada Hujan
Clear:Cerah
Hazy:Berjerebu
Windy:Berangin
No rain:Tiada Hujan
Cloudy:Mendung
Cloudy over coastal areas:Mendung di kawasan pantai
Cloudy over inland areas:Mendung di kawasan pedalaman
Rain:Hujan
Intermittent rain occasionally moderate:Hujan sekejap-sekejap kadangkala sederhana
Intermittent rain occasionally heavy:Hujan sekejap-sekejap kadangkala lebat
Widespread intermittent rain:Hujan sekejap-sekejap yang menyeluruh
Isolated rain:Hujan di satu dua tempat
Isolated rain over coastal areas:Hujan di beberapa tempat di kawasan pantai
Isolated rain over inland areas:Hujan di beberapa tempat di kawasan pedalaman
Scattered rain:Hujan curah/sementara di satu dua tempat
Scattered rain over coastal areas:Hujan curah/sementara di kawasan pantai
Scattered rain over inland areas:Hujan curah/sementara di kawasan pedalaman
Showers:Hujan curah
Isolated showers:Hujan curah di satu dua tempat
Isolated showers over coastal areas:Hujan curah di kawasan pantai
Isolated showers over inland areas:Hujan curah di kawasan pedalaman
Thunderstorms:Ribut petir
Isolated thunderstorms:Ribut petir di satu dua tempat
Scattered thunderstorms:Ribut petir di beberapa tempat
Widespread thunderstorms:Ribut petir di kebanyakan tempat
    Reply ↓

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