Errata for Introduction to Applied Linear Algebra – Vectors, Matrices, and Least Squares.

If you find an error in the book not listed here, please do let us know about it.

These (small) typos will be corrected in the second printing.

• p17, first paragraph. a_n should be a_m.

• p26, exercise 1.10. Missing “the” in “in final”.

• p42, exercise 2.3. “affine function of x” should be “affine function of f”.

• p47, line 8. “fourth” should be “third”.

• p57, paragraph above Verification of triangle inequality. Replace “scalar” with positive scalar.

• p59, table 3.2. The 3,5 entry (for Academy A., Super Bowl) should be 86.1.

• p65, exercise 3.12. Title should be “Nearest point on a line”.

• p78, figure 4.5. Delete “scale” on the y-axis.

• p95, line 2. “This in turns implies” should be “This in turn implies”.

• p99, line 13. i<k should be i<=k.

• p99, line -7. a_1 should be a_i.

• p100, middle. “by conclusion 3” should be “by conclusion 4”.

• p102, middle bottom. “can we can” should be “we can”.

• p117, section 6.3.3, line -6. alpha beta should be beta gamma.

• p121, document scoring: “A in an” should be “A is an”

• p121, Total price from multiple suppliers. Last two mentions of “N” should be“m”.

• p127, exercise 6.18. Add condition m >= n.

• p137, middle. “ie, i-j=k-1” should be “i-j = k+1”.

• p159, exercise 8.1. “f(x)=Gx” should be “g(x)=Gx”.

• p140, in Input-output convolution system. “lengths of u and y, n” should be lengths of u and y, m“. Also, ”for k<0 or k>n’ should be “for k<=0 or k>m”.

• p161, exercise 8.12 (b). w_1=1/2, w_2=1/2 should be w_1=1, w_2=1.

• p170, “t=1,2,3,…” should be “k=1,2,3,…”.

• p170, line -5. “u_t” should be “f_k”.

• p171, “k=250” should be “k=600”.

• p171, “2.5 seconds” should be “6 seconds”.

• p185, line -15. “Ax+b” should be “Az+b”.

• p189, line 3 second equation is missing one term.

• p189, line 7,8 index “t+l-j” should be “t+l”; “time t+l=j” should be “t+1”.

• p191, exercise 10.4. “four” should “five”.

• p191, exercise 10.5. b should be b^T.

• p193, exercise 10.16 (c). N should be n; also “correlation matrix” should be “covariance matrix”.

• p196, exercise 10.32. “It can shown” needs “be”.

• p198, exercise 10.41. z_N should be z_k.

• p202, top equation, righthand side should be (1/2,2/3,-2/3).

• p205. “they called dual bases” should be “they are called dual bases”.

• p205, line -9. Remove two transposes in equation beta = B^Tx = …

• p210, the rows of the matrix A^{-1} are reversed.

• p211, coefficient c_4 should be coefficient c_1, and coef c_2 should be c_3.

• p218, exercise 11.11. “range x=0 to x=6” should be “range t=0 to t=6”.

• p221, first word should be “are”.

• p241, exercise 12.12 add “is” after “placement problem”.

• p242, exercise 12.14 “for” should be capitalized, and part (b), indexes should be k+1, not k.

• p247, equation (13.1). Remove hat from f_j.

• p251, line -12. “dependent” should be “independent”.

• p275, middle of page. Bottom formula (for x_1>1.5) is missing term -1.5 theta_3.

• p259, line -15. “0.98^circ F” should be “1.01^circ F”.

• p262, last line. “test set performance” should be “test set RMS error”.

• p273. f(x) should be f_i(x); add i=1,…,k.

• p280, exercise 13.5, last line. “maps 2-vectors” should be “maps 3-vectors”

• p287, table 14.1, bottom row, second column should be N_{fn}+N_{tn}.

• p293, caption of Table 14.6. “classier” should be “classifier”.

• p300, 4 lines below “Skewed decisions.” Subscript l should be k.

• p301, line 4. hat theta_k should be hat theta_K.

• p302, line 9. “data set” should be “training set”.

• p307, exercise 14.10, part (b). “K(K-1)2 least squares problem” should be “K(K-1)2 least squares problems”.

• p315. “objective it to keep” should be “objective is to keep”.

• p318. line 10, b should be y.

• p329. “cos” should be “sin” in the two displayed equations.

• p368, section 17.2.1. Period after t=1,…,T should be a comma.

• p372, figure 17.7. “constant” should be “linear”.

• p384, Chemical equilibrium, line -9. “generation of the n reactants” should be "generation of the n products”.

• p394, line = -6. pnom = (1,1), dnom = (3,1), snom = (2,2)

• p396, figure 18.8 caption. Missing righthand ) in cost function.

• p402, line 9. “(18.15)” should be “(18.17)”. p422, (19.7). L(x,mu) should be L(x,z).

• p429. “constrained least problem” should be “constrained nonlinear least squares problem”.

• p441. “C is m x p” should be “C is n x p” (so the product AC makes sense).

• p448, section C3. In problem statement f(x) should be h(x).

• p449, “but hat x” should be “but x”.

• p449, third displayed equation. nabla (gradient) symbol missing between z_hat_p and g_p.