Errata

Computer Science Programming Basics in Ruby

Errata for Computer Science Programming Basics in Ruby

Submit your own errata for this product.

The errata list is a list of errors and their corrections that were found after the product was released.

The following errata were submitted by our customers and have not yet been approved or disproved by the author or editor. They solely represent the opinion of the customer.

Color Key: Serious technical mistake Minor technical mistake Language or formatting error Typo Question Note Update

Version Location Description Submitted by Date submitted
Printed Page i and ii
First sentence

In pages i and ii, the title of the book appears as "Computer Science Programming Basics with Ruby", while the front and back covers have "Computer Science Programming Basics in Ruby".

 Francisco Milan  Nov 21, 2014 
Printed Page 9
Exercise 6

On page 9 the exercise 6 reads:

"A cable company must use cables to connect 15 homes..."

On page 10, the Figure 1-5 only shows 13 homes.

 Francisco Milan  Nov 13, 2014 
PDF Page 17
last paragraph

"64 bytes are called a double or long word"
------------

should that not be:

64 bits

or

8 bytes

 Anonymous  Aug 03, 2013 
Printed Page 18
Final paragraph

Misleading description of Unicode: "The first 256 characters are contained in one byte and are identical... to ASCII" - this confuses the representation of Unicode (the first 128 characters have the same representation as ASCII) with the actual characters. The final paragraph of the 'Strings' section on p28 repeats this confusion.

 DoubleLife  May 13, 2013 
Printed Page 19
Gem of Wisdom

The second sentence in the Gem of Wisdom contains the word "only" twice: "However, a computer only understands only instructions..."

 Francisco Milan  Nov 18, 2014 
Printed Page 20
2nd paragraph

Text glosses over the concept of an editor as opposed to a word processor. I think this is worth clarifying to avoid a student 'editing' a program as an ordinary 'Word' document and not getting the results they expect.

 DoubleLife  May 13, 2013 
Printed Page 33

The text shows the following:
"Step 2: Write Out the Problem in Plain Language"
Before writing out the problem, remember..."

Instead, it should say something like:
"Step 2: Write Out the Solution in Plain Language"
Before writing out the solution, remember..."



 Francisco Milan  Nov 20, 2014 
Printed Page 67
Example 5-7

The comment in line 4 reads as follows: "# i: [0, 100]", but it should read "# i: [1, 100]", since the variable "i" is initialized with a value of "1" in line 2.

 Francisco Milan  Nov 25, 2014 
Printed Page 67
Example 5-7

The comment in line 9 reads as follows: "# Test divisibility of i from [0, i/2]", but it should read "# Test divisibility of i from [1, i/2]", since the variable "i" is initialized with a value of "1" in line 2.

 Francisco Milan  Nov 25, 2014 
Printed Page 68
4th bullet

The fourth bullet reads as follows: "Line 10 begins an inner loop that tests all values from 2 to i/2", but it should read "Line 10 begins an inner loop that tests all values from 1 to i/2" , since the variable "i" is initialized with a value of "1" in the line 2 of Example 5-7 (page 67).

 Francisco Milan  Nov 25, 2014 
Printed Page 69
First sentence (after the Gem of Wisdom paragraph)

The first sentence reads as follows: "... may need to try to find all primes from 1 to 10,000 (change line 2 from 100 to 10,000) to really see a difference.", but it should read: "... may need to try to find all primes from 1 to 10,000 (change line 5 from 100 to 10,000) to really see a difference."

 Francisco Milan  Nov 25, 2014 
Printed Page 83
Last paragraph

In the last paragraph there's a sentence that reads:
"That is, the hash table arr['Geraldo'] identifies Geraldo's test scores even though Geraldo is not a integer."

That sentence should read:
"That is, the hash table scores['Geraldo'] identifies Geraldo's test scores even though Geraldo is not a integer."

 Francisco Milan  Nov 29, 2014 
Printed Page 94
Code sample

I think that there is an error in the sample code for the bubble sort.

The text states that bubble sort works by 'swapping neighboring elements' (p. 93) and that the inner loop in the sample code 'swaps all elements that are larger than their next successive element' (p. 94).

However, it appears to me that this inner loop is not comparing pairs of neighbouring elements. It is comparing one element with each of it's successive elements, and swapping that element with any element that it is greater than.

 Anonymous  Apr 09, 2016