Difference between revisions of "Python"

Latest revision as of 12:23, 6 May 2019

IIT Bombay is leading the effort to popularise Python for Scientific Computing in India. This is part of the Free and Open source Software for Science and Engineering Education (http://fossee.in) project, supported by the National Mission on Education through ICT of MHRD.

IIT Bombay is using Spoken Tutorials (http://spoken-tutorial.org) to create learning material for FOSS. This is the main page for the organisation of the scripts required for Standard two day workshop we conduct on "Python for Scientific Computing" spoken tutorials.

Learners: Science and Software Engineer Students

Note: Each numbered topic corresponds to a single spoken tutorial. Each bulleted point corresponds to a command or topic that must be covered in the given spoken tutorial.

Module 1: Basic Plotting

Getting started with ipython

• invoking ipython
  if there's a problem, pre-requisites are not met.

• getting out
  

• explain the prompt
  

• typing commands
  
  • 1+2
    
    • careful wording to differentiate from print
      
  • print 1+2
    
  • history (up, down arrows)
    
  • backspace, delete key
    
  • tab completion
    
    • ab
      
    • a
      
    • rou
      
    • ro
      
    • r
      

• abs?, round?
  

• handling typing errors
  
  • round(2.48,
    • close it
    • use ^C

Using the plot command interactively

• ipython -pylab
  
  • pylab brings in the libraries necessary for Scientific Computing.
    

• linspace,
  

• len
  

• clf
  

• plot
  

• using the plot ui
  

Embellishing a plot

• Title
  

• Label
  

• line width, color, style
  

• annotations
  

Saving plots

• basic savefig
  

• png, pdf, ps, eps, svg
  

• going to OS and looking at the file
  

Multiple plots

• overlays
  
  • linspace
    
    • give one with very few points, more points
      
    • show smoothness of the curve
      

• legend
  

• figure 1, figure2
  

• subplots
  

Additional features of IPython

• %save, %history, %run
  

Module 2: Plotting Experimental Data

loading data from files

• loadtxt with unpack=True
  
  • primes.list (one col)
    
  • pendulum.txt (two col)
    

Plotting the data

• plot L vs. T²
  
  • using square function
    

• problem with 3 cols
  
  • 3rd column is error
    
  • error bar
    

Other types of plots

• scatter
  

• pie chart
  

• bar chart
  

• log
  

• illustration of other plots, matplotlib help
  

Module 3: using Sage

Getting started with sage notebook

• about sage
  
  • …
    

• starting the notebook server
  

• using the UI
  
  • typesetting & print
    
  • selecting language
    
    • sage
      
    • LaTeX
      
    • python
      
  • help
    
    • sum(<tab>
      
    •  ?
      

Getting started with symbolics

• symbolic expressions
  
  • built-in constants & functions
    
  • algebraic expressions,
    
  • series
    
  • integration, differentiation
    
  • matrices
    

• symbolic functions
  
  • defining
    

• simplification
  

• finding roots & factors
  

• substituting expressions
  

• output formats
  

Using Sage

• ABCD
  
  • Degree
    
    • RBT - U
      

• Calculus
  
  • limits
    
  • differentiation
    
  • integration
    
    • indefinite
      
    • definite
      
  • piece-wise functions
    
  • differential equations
    
  • maxima, minima
    

• Linear Algebra
  
  • Vectors and Matrices
    
    • constructions
      
  • Vector Operations
    
    • linear combination
      
    • dot
      
    • cross
      
    • pairwise
      
  • Matrix Operations
    
    • linear combination
      
    • matrix multiplication
      
    • inverse
      
    • transpose
      
    • adjoint
      
    • rank
      
    • determinant
      
    • trace
      
    • norm
      
  • Solving equations
    
  • Eigenvalues, eigenvectors
    

• Graph Theory
  

• Number Theory
  

Using sage to teach

• @interact
  

• 2D, 3D graphics
  

• Graph Theory
  

• Share, Publish
  

• print
  

Module 4: Handling Large Data Files

Getting started with lists

• empty
  

• filled lists
  
  • heterogenity
    

• accessing
  

• len
  

• append elements
  

• del (+ remove)
  

Getting started with for

• blocks in python
  
  • (indentation)
    

• blocks in ipython
  
  • … prompt
    
  • hitting enter
    

• for with a list
  

• range function
  

Getting started with strings

• strings
  
  • single, double, triple quoted
    

• accessing elements
  

• show immutability
  

• tell that there are methods for manipulation
  

Getting started with files

• show file object
  

• read the file with read
  

• closing the file
  

• for line in file:
  

• print a line
  

• append the lines to a list
  

Parsing data

• explain what is parsing
  

• strip (with strings)
  

• split (with strings)
  
  • with delimiters
    
    • specify space as delimiter
      

• datatype conversion
  

• reading from files
  
  • do the same problem done with loadtxt (for pendulum)
    
  • basic parse sslc text
    

Statistics

• mean
  
  • summing
    

• median
  

• std
  

Module 5: Arrays and Matrices

Getting started with arrays

• why arrays
  
  • speed - simply say
    
  • array level operations
    

• creating arrays
  
  • direct data
    
  • list conversion
    
  • homogeneous
    
  • builtins - identitiy, zeros,
    

• array operations
  
  • + - * /
    

Accessing parts of arrays

• accessing individual elements
  

• changing individual elements
  

• slicing, striding
  

• image manipulation
  

Matrices

• creating matrices
  
  • direct data
    
  • list conversion
    
  • builtins - identitiy, zeros,
    

• matrix operations
  
  • + - * /
    
  • dot
    
  • inv
    
  • det
    
  • eig
    
  • norm
    
  • svd
    

Least square fit

• show pendulum
  
  • use loadtxt
    

• lstsq
  

Module 6: Python Language: Basics

Basic datatypes & operators

• int
  
  • L, long
    

• float
  
  • repr, str
    

• complex
  

• boolean
  

• conversion functions
  

• sequence datatypes & mutability
  
  • list available sequence datatypes
    
    • string
      
    • list
      
    • tuple
      
  • mutability
    
  • conversion
    
  • common stuff
    
    • len
      
    • in
      
    • max, min, sum, sorted, reversed
      
    • accessing individual elements
      
    • slicing, striding
      

I/O

Input Output in Python

Conditionals

• if, elif, else
  

• pass
  

Loops

• while
  

• for
  

• pass, break, continue
  

Module 7: Python Language: Datastructures

Manipulating lists

• concatenation
  

• slicing
  

• striding
  

• .sort
  

• sorted
  

• .reverse
  

• reversed
  

Manipulating strings

• upper, lower,
  

• replace
  

• slicing
  

• [::-1]
  

• reversed
  

• palindrome check
  

Getting started with tuples

• immutability
  

• tuple packing, unpacking
  
  • a, b = b, a
    

• accessing individual elements
  

• slicing, striding
  

Dictionaries

• empty
  

• filled
  

• accessing via keys
  

• .values(), .keys()
  

• in
  

• iteration
  

Sets

Sets

About sets in python

Module 8: Python Language: Advanced

Getting started with functions

• defining function
  

• arguments
  

• docstrings
  

• return values
  
  • can return multiple values

• code reading exercises
  

Advanced features of functions

• default arguments
  

• keyword arguments
  

• built-in functions show off
  

Using python modules

• scipy
  

• pylab
  

• sys
  

Writing python scripts

• import
  

Testing and debugging

Testing and debugging