Las Listas 2 y las corporasDay 12 - 2/6/15SPAN 4350

Cultura computacional en español

Harry Howard

Tulane University

Organización del curso

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http://www.tulane.edu/~howard/Span4350/

http://www.tulane.edu/~howard/CompCultES/1. cultcomp2. python 3. cadenas4. unicode 5. exreg 6. listas 7. nltk_archives

Una lista es una secuencia de objetos entre corchetes.

Repaso

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CultCompES, Prof. Howard, Tulane University

La mayoría de los métodos de las cadenas funcionan con las listas

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split() vs. join()

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§6. Las listas

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CultCompES, Prof. Howard, Tulane University

6.2.3. ¿Qué métodos se permiten con una lista pero no con una cadena?1. >>> L1 = ['Miguel', 'Cervantes']2. >>> L1.append('de Saavedra') 3. >>> del L1[2] 4. >>> L1.insert(1, 'de Saavedra') 5. >>> L1.remove('de Saavedra') 6. >>> L1[0] = 'Miguelito' 7. >>> L1.append('de Saavedra') 8. >>> L1.pop(2) 9. >>> L1.reverse()

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http://www.tulane.edu/~howard/CompCultES/nltk_archives.html

7. NLTK and Internet corpora

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CultCompES, Prof. Howard, Tulane University

Configurar el directorio de trabajo global

Crea una carpeta "pyScripts" en tu carpeta de documentos.

En Spyder > Preferences > Global Working directory: "At start-up, the global working directory is …

the following directory (navega a "pyScripts" y pínchala)

"Files are opened from: … the global working directory.

"Files are created in: … the global working directory.

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7.1.1. How to navigate folders with os1. >>> import os

2. >>> os.getcwd()

3. '/Users/harryhow/Documents/pyScripts'

4. # if the path is not to your pyScripts folder, then change it:

5. >>> os.chdir('/Users/{your_user_name}/Documents/pyScripts/')

6. >>> os.getcwd()

7. '/Users/{your_user_name}/Documents/pyScripts/'

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7.1.2. Project Gutenberghttp://www.gutenberg.org/ebooks/28554

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7.1.3. How to download a file with urllib and convert it to a string with read()1. >>> from urllib import urlopen

2. >>> url = 'http://www.gutenberg.org/cache/epub/28554/pg28554.txt'

3. >>> download = urlopen(url)

4. >>> downloadString = download.read()

5. >>> type(downloadString)

6. >>> len(downloadString) # 35739?

7. >>> downloadString[:50]

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7.1.4. How to save a file to your drive with open(), write(), and close() # it is assumed that Python is looking at your

pyScripts folder >>> tempFile = open('Cervantes.txt','w') >>> tempFile.write(downloadString.encode('utf8')) >>> tempFile.close() # import os if you haven't already done so >>> os.listdir('.')

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7.1.5. How to look at a file with open() and read()

1. >>> tempFile = open('Cervantes.txt','r')

2. >>> text = tempFile.read()

3. >>> type(text)

4. >>> len(text)

5. >>> text[:50]

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7.1.6. How to slice away what you don’t need

1. >>> text.index('*** START OF THIS PROJECT GUTENBERG EBOOK')

2. 499

3. >>> lineIndex = text.index('*** START OF THIS PROJECT GUTENBERG EBOOK')

4. >>> startIndex = text.index('\n',lineIndex)

5. >>> text[:startIndex]

6. >>> text.index('*** END OF THIS PROJECT GUTENBERG EBOOK')

7. >>> endIndex = text.index('*** END OF THIS PROJECT GUTENBERG EBOOK')

8. >>> story = text[startIndex:endIndex]

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Now save it as “Wub.txt”

1. # it is assumed that Python is looking at your pyScripts folder

2. >>> tempFile = open('Cervantes.txt','w')

3. >>> tempFile.write(story.encode('utf8'))

4. >>> tempFile.close()

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P3 sobre unicode y listas§7. Corpora

El próximo día

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