Seite - 97 - in Programming for Computations – Python - A Gentle Introduction to Numerical Simulations with Python 3.6, Band Second Edition

4.3 Exercises 97 4.3 Exercises Exercise4.1:ErrorswithColon, Indent, etc. Write the program ball_function.py as given in the text and confirm that the program runs correctly. Then save a copy of the program and use that program during the followingerror testing. Youaresupposedtointroduceerrorsinthecode,onebyone.Foreacherrorintro- duced, save and run the program,and comment how well Python’s response corre- sponds to the actualerror.Whenyouarefinishedwithoneerror, re-set theprogram tocorrectbehavior (andcheck that it works!)beforemovingon to thenexterror. a) Change the first line fromdef y(v0, t): todef y(v0, t), i.e., remove the colon. b) Removethe indent in frontof thestatementg = 9.81 inside thefunctiony, i.e., shift the text fourspaces to the left. c) Now let the statementg = 9.81 inside the functiony have an indent of three spaces (while the remainingtwo linesof the functionhavefour). d) Remove the left parenthesis in the first statementdef y(v0, t): e) Change the first line of the function definition from def y(v0, t): to def y(v0):, i.e., removethe parametert (and thecomma). f) Change the first occurrence of the command print(y(v0, time)) to print(y(v0)). Filename:errors_colon_indent_etc.py. Exercise4.2:ReadingCode1 a) Read the followingcode and predict the printout producedwhen the programis executed. def f(x): return x**2 def g(x): return 2*x for x in [1, 5, 6, 9]: if x < 5: # case 1 print(f(x)) elif x == 5: # case 2 print(2*f(x)) elif x > 5 and x < 8: # case 3 print(f(x+4) + g(x*2) - g(2)) else: # case 4 y = x + 2 print(g(y))