Tutorial by Examples: e

By taking Treeview: Basic example, it can be shown how to customize a basic treeview. In this case, we create a style "mystyle.Treeview" with the following code (see the comments to understand what each line does): style = ttk.Style() style.configure("mystyle.Treeview", highli...

A simple OGL 4.0 GLSL shader program that shows the use of a interface block and a uniform block on a Cook-Torrance microfacet light model implementation. The program is executed with a phyton script. To run the script, PyOpenGL and NumPy must be installed. An Interface Block is a group of GLSL in...

The widget ttk.progress is useful when dealing with long computations so that the user knows that the program is running. Following, an example updating a progressbar each 0.5 seconds is given: Function updating the progressbar def progress(currentValue): progressbar["value"]=curren...

from chempy import Substance ferricyanide = Substance.from_formula('Fe(CN)6-3') ferricyanide.composition == {0: -3, 26: 1, 6: 6, 7: 6} True print(ferricyanide.unicode_name) Fe(CN)₆³⁻ print(ferricyanide.latex_name + ", " + ferricyanide.html_name) Fe(CN)_{6}^{3-}, Fe(CN)<sub>6&...

from chempy import balance_stoichiometry # Main reaction in NASA's booster rockets: reac, prod = balance_stoichiometry({'NH4ClO4', 'Al'}, {'Al2O3', 'HCl', 'H2O', 'N2'}) from pprint import pprint pprint(reac) {'Al': 10, 'NH4ClO4': 6} pprint(prod) {'Al2O3': 5, 'H2O': 9, 'HCl': 6, 'N2': 3} ...

from chempy import Equilibrium from sympy import symbols K1, K2, Kw = symbols('K1 K2 Kw') e1 = Equilibrium({'MnO4-': 1, 'H+': 8, 'e-': 5}, {'Mn+2': 1, 'H2O': 4}, K1) e2 = Equilibrium({'O2': 1, 'H2O': 2, 'e-': 4}, {'OH-': 4}, K2) coeff = Equilibrium.eliminate([e1, e2], 'e-') coeff [4, -5...

from chempy import Equilibrium from chempy.chemistry import Species water_autop = Equilibrium({'H2O'}, {'H+', 'OH-'}, 10**-14) # unit "molar" assumed ammonia_prot = Equilibrium({'NH4+'}, {'NH3', 'H+'}, 10**-9.24) # same here from chempy.equilibria import EqSystem substances = ...

from chempy.electrolytes import ionic_strength ionic_strength({'Fe+3': 0.050, 'ClO4-': 0.150}) == .3 True

from chempy import ReactionSystem # The rate constants below are arbitrary rsys = ReactionSystem.from_string("""2 Fe+2 + H2O2 -> 2 Fe+3 + 2 OH-; 42 2 Fe+3 + H2O2 -> 2 Fe+2 + O2 + 2 H+; 17 H+ + OH- -> H2O; 1e10 H2O -> H+ + OH-; 1e-4 Fe+3 + 2 H2O -...

Authorize yourself, you will be navigated to Google Sign In page. $ gcloud auth login Initialize or reinitialize the gcloud, you can set your configurations here. $ gcloud init Display information about the current gcloud environment. $ gcloud info Display the list of active SDK configur...

Create a Cloud SQL instance $dsn = "/cloudsql/PROJECT:REGION:INSTANCE;dbname=DATABASE"; $user = "USER"; $password = "PASSWORD"; $db = new PDO($dsn, $user, $password); //Whatever is your favorite MySQL connection method The important part here is /cloudsql/PRO...

App Engine does not allow writing to files, instead write to and read from Cloud Storage. Write to Cloud Storage $file = 'gs://<your-bucket>/hello.txt'; file_put_contents($file, 'hello world'); Read from Cloud Storage $contents = file_get_contents($file); var_dump($contents);

Detailed instructions on getting microsoftgraph set up or installed.

"""PyAudio Example: Play a wave file (callback version).""" import pyaudio import wave import time import sys if len(sys.argv) < 2: print("Plays a wave file.\n\nUsage: %s filename.wav" % sys.argv[0]) sys.exit(-1) wf = wave.open(sys.arg...

"""PyAudio Example: Play a wave file.""" import pyaudio import wave import sys CHUNK = 1024 if len(sys.argv) < 2: print("Plays a wave file.\n\nUsage: %s filename.wav" % sys.argv[0]) sys.exit(-1) wf = wave.open(sys.argv[1], 'rb') # i...

The QSqlDatabase class provides an interface for accessing a database through a connection. An instance of QSqlDatabase represents the connection. The connection provides access to the database via one of the supported database drivers. Make sure to Add QT += SQL in the .pro file. Assume an SQ...

It's often convenient to separate the SQL query from the actual values. This can be done using placeholders. Qt supports two placeholder syntaxes: named binding and positional binding. named binding: QSqlQuery query; query.prepare("INSERT INTO employee (id, name, salary) VALUES (:id, :name,...

To shelve an object, first import the module and then assign the object value as follows: import shelve database = shelve.open(filename.suffix) object = Object() database['key'] = object

import shelve d = shelve.open(filename) # open -- file may get suffix added by low-level # library d[key] = data # store data at key (overwrites old data if # using an existing key) data = d[key] # retrieve a C...

The simplest way to use shelve is via the DbfilenameShelf class. It uses anydbm to store the data. You can use the class directly, or simply call shelve.open(): import shelve s = shelve.open('test_shelf.db') try: s['key1'] = { 'int': 10, 'float':9.5, 'string':'Sample data' } finally: ...