the world is a pixel
Python: capturando o retorno da linha anterior
Lendo um código eu me deparei com o operador _ do Python.
Ele é uma variável especial para ser usada quando estamos trabalhando no console e queremos referenciar o valor de retorno da linha anterior.
Por exemplo:
>>> 42 42 >>> 1 + _ 43 >>> import os >>> os.getcwd() '/home/silveira' >>> _ + '/pasta' '/home/silveira/pasta'
Eu gostaria ter sabido disso quando eu usava o console do Python pelo meu antigo celular…
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Python, flatten a list
Surprisingly python doesn’t have a shortcut for flatten a list (more generally a list of lists of lists of…). I made a simple implementation that doesn’t use recursion and tries to be written clearly. I get a element from a “bad” list (a list that can have another lists). If the element is not a [...]
Contando Algarismos Em Um Intervalo
29 January, 2010 - 8:21 pm
Tags: compreensão de lista, Programação, programação funcional, Python
Posted in english | 3 comments
Quantos zeros tem entre um e mil? É mais fácil responder perguntas desse tipo escrevendo pequenos programas usando o suporte a programação funcional e compreensão de lista que algumas linguagens como Python oferecem. Para contar os zeros de um número, transformamos ele em uma string e contamos quantas substrings ’0′ ele contém. Por exemplo o [...]
Easily Sortable Date and Time Representation
20 January, 2010 - 10:55 pm
Tags: date, datetime, ISO 8601, Jochen Voss, Markus Kuhn, programming, Python, representation, sort, sorting, time
Posted in english | No comments
I was looking for a date and time representation useful for registering stock quotes in a simple plain file. I found that the standard ISO 8601 is just the answer for this, it’s called “Data elements and interchange formats — Information interchange — Representation of dates and times”. Here is a example: 2010-01-20 22:14:38 There’s this [...]
Extração de Dados e Fundos de Investimento do Banco do Brasil
11 January, 2010 - 9:02 pm
Tags: ações, aplicações, Banco do Brasil, bolsa de valores, CRON, Data Mining, fundo de investimento, fundos, fundos de investimento, JSON, Mineração de Dados, Python, screen scraping, Web Harvest, web scraping, XML, yaml
Posted in english | 4 comments
Eu não achei onde coletar os dados diários de rentabilidade dos fundos de investimento do Banco do Brasil em formato bem estruturado. Num mundo ideal as coisas seriam assim, você faria uma requisição numa url como esta: http://bb.com.br/apps/rentabilidade?fundo=Siderurgia&saida=xml E ele cuspiria um XML com as informações da rentabilidade diária desse fundo, isso se eu não [...]
Python Fast XML Parsing
25 December, 2009 - 3:04 pm
Tags: dtd, expat, game, programming, pygame, Python, sax, schema, urllib, XML
Posted in english | 2 comments
Here is a useful tip on Python XML decoding. I was extending xml.sax.ContentHandler class in a example to decode maps for a Pygame application when my connection went down and I noticed that the program stop working raising a exception regarded a call to urlib (a module for retrieve resources by url). I noticed that [...]
Tiled TMX Map Loader for Pygame
I’m using the Tiled Map Editor for a while, I even wrote that tutorial about it. It’s a general purpose tile map editor, written in Java but now migrating to C++ with Qt, that can be easily used with my set of free pixelart tiles. A map done with Tiled is stored in a file [...]
Pygame: Running Orcs
11 December, 2009 - 7:47 am
Tags: game, orc, Pixelart, programming, pygame, Python
Posted in english | 1 comment
Here is a Pygame Sprite animation using the approach presented by Joe Wreschnig and Nicolas Crovatti. It’s not yet exactly what I need but is very suitable. import pygame, random from pygame.locals import * class Char(pygame.sprite.Sprite): x,y = (100,0) def __init__(self, img, frames=1, modes=1, w=32, h=32, fps=3): pygame.sprite.Sprite.__init__(self) original_width, original_height = img.get_size() self._w = [...]
Pygame Simple Key Handling
10 December, 2009 - 12:50 am
Tags: pygame, Python
Posted in english | No comments
Here’s a simple key handle in Pygame wheres you move a circle using keyboard. import pygame from pygame.locals import * def main(): x,y = (100,100) pygame.init() screen = pygame.display.set_mode((400, 400)) while 1: pygame.time.delay(1000/60) # exit handle for event in pygame.event.get(): if event.type == QUIT: return elif event.type == KEYDOWN and event.key == K_ESCAPE: return [...]
Pygame, Simple Space Effect
12 August, 2009 - 7:14 am
Tags: game, game development, game loop, list comprehension, pygame, Python, SDL, Simple Direct Layer, sliding stars, Space, space effect, stars
Posted in english | 3 comments
This is a simple space effect of sliding stars using Pygame. Direct link to video: simple_space_effect_01.ogv We set some constants like the screen size and the number N of star we want. N = 200 SCREEN_W, SCREEN_H = (640, 480) Using list comprehension we create a list of random points in the screen, that will [...]
JavaFX, Retrieving non XML/JSON data from clouds
31 May, 2009 - 12:34 pm
Tags: HttpRequest, JavaFX, JSON, PullParser, Python, XML, Zembly
Posted in english | 6 comments
Usuually on JavaFX we grab data using HttpRequest from external resources on formats like JSON or XML. I showed how to get it on the post Reading Twitter with JavaFX and how to parse it using PullParser on the post Parsing a XML sandwich with JavaFX. Another day I need to grab and interpret some [...]
2 February, 2008 - 8:49 am
Olá Silveira, sou de Fortaleza, mais precisamente João XXIII. Há uma comunidade python aqui? Como juntar-se à mesma?
Valeu!
2 February, 2008 - 10:26 am
Olá Sérgio, eu não conheço nenhuma comunidade aqui, será que existe um Python Users Group? PUG?