Insight Through Computing

p.13 P1.1.5 2010/09/19

In the example below the table of formulae, the divisor for calculating Vol20 should be 12, not 4.

    Vol20 = ((15 + 5*sqrt(5))/12)*E^3;

pp.17-19 Code fragments %Solution1, %Solution2, %Solution3 2011/08/31: In each fragment, the caluclation of xc should be done outside the if statement. The complete script Eg1_2 given on page 20 is correct.

p.43 P2.2.7 2010/02/10

The given sine and cosine values are switched around. The correct values are

    cos(pi/3)=1/2;  sin(pi/3)=sqrt(3)/2;  sin(2*pi/3)=sqrt(3)/2;

p.48-50 and Eg3_1 2012/02/13: The development of the program to calculate the "best" p/q is unnecessarily complicated. The variable e0 for intermediate "best" error, the variable p0 for intermediate "best" p, and the statements associated with these variables are not necessary. Just updating err_pq, pBest, and qBest directly everytime after finding a smaller error is all that is necessary. The resulting simpler code is posted on the Software page as SimplerEg3_1.m.

p.60 P3.2.6 2014/03/17: In the second last sentence, the final term in the sequence to display is B(m,r), not B(m,m).

p.60 P3.2.7 2014/03/17: Develop a program that prints t0, t1, ..., t26. Start at t0, not t1.

p.70 and Eg4_1 2014/03/17: The script comment and the title statement of the plot contain an error: the argument to the function exp should be -x/2, not x/2. The code for the calculation of the function value is correct though. The file Eg4_1.m posted on the Software page has been corrected.

p.71 Second last code fragment 2011/10/27: One of the vector indices shown is wrong for replacing the statement x(2) = x(3) + x(4). The correct fragment should be
i = 1;
x(i+1) = x(i+2) + x(i+3);
and not x(i) = x(i+2) + x(i+3)

p.72 First code fragment 2011/10/27: The last statement should assign the value 30 to x(4), not the value 35.

p.81 First code fragment 2011/10/27: In the second call to the fill function, there should be a comma to separate the arguments y+1 and the color vector, like this:
fill(x,y+1,[0.4 0.6 1.0])

p.141 Second line on the page 2011/08/30: The built-in function used should be all, not any. That is, the value of all(x < y) is 1 if and only if x(k) < y(k) for every subscript k.

p.142 P6.1.18 2014/10/02: The stopping condition of the game "Gap N" is the difference between the number of heads and the number of tails being N. However, the expression given below the example sequence was wrong. It should read |#tails - #heads| and not |#tosses - # heads|.

p.181 Last paragraph 2022/05/09: Eight perfect shuffles are needed to restore an ordinary deck of playing cards. The typo in the last paragraph stated seven cards. The script Eg8_1 gives the correct result, as shown on Figure 8\_1 on the next page.

p.183 Last sentence in Problem Statement section 2012/03/13: The deck sizes should be n = 2:2:60 (not 2:2:100) in order to match the code in Eg8_1.

p.189 Code block near the bottom of the page 2011/05/10

The boolean expression for the if statement should be

    x(k+1) < x(k)

and not x(k+1) < x(x).

p.241 Function ShowRect 2012/11/10

The vector arguments to the plot function should have length 5, not 4, since it is necessary to "wrap around" to the first vertex in order to draw a closed rectangle. The original code draws a sideways 'U' only, missing one edge of the rectangle. Here is the correct call to the plot function:

     plot([R.left R.right R.right R.left R.left],...
          [R.bot R.bot R.top R.top R.bot], 'k','Linewidth',2)

p.269 Code block near the top of the page 2010/01/24

The loop body is missing the statement s = C{k}; The loop should be

   for k=1:length(C)

      s = C{k};

      P(k) = str2num(s(67:75));
      Lat(k) = str2num(s(137:146));
      Long(k) = str2num(s(147:157)); 
   end

p.341 Last sentence before Figure 14.7 2014/03/03: The top node is the root node while the 81 (not 27) nodes across the bottom are leaf nodes.

p.342 P14.1.3 2011/05/10: Part (b) of the problem statement should read "... then the reverse of s is the concatenation of the reverse of s(2:n) and s(1) in that order." The subvector was incorrectly specified as s(1:n-1).

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p.181 Last paragraph 2022/05/09: Eight perfect shuffles are needed to restore an ordinary deck of playing cards. The typo in the last paragraph stated seven cards. The script Eg8_1 gives the correct result, as shown on Figure 8\_1 on the next page.

p.142 P6.1.18 2014/10/02: The stopping condition of the game "Gap N" is the difference between the number of heads and the number of tails being N. However, the expression given below the example sequence was wrong. It should read |#tails - #heads| and not |#tosses - # heads|.

p.60 P3.2.6 2014/03/17: In the second last sentence, the final term in the sequence to display is B(m,r), not B(m,m).

p.60 P3.2.7 2014/03/17: Develop a program that prints t0, t1, ..., t26. Start at t0, not t1.

p.70 and Eg4_1 2014/03/17: The script comment and the title statement of the plot contain an error: the argument to the function exp should be -x/2, not x/2. The code for the calculation of the function value is correct though. The file Eg4_1.m posted on the Software page has been corrected.

p.341 Last sentence before Figure 14.7 2014/03/03: The top node is the root node while the 81 (not 27) nodes across the bottom are leaf nodes.